Logan's Gen 3 Coupe-R Build

[Logan]

Background: Grew up in SW Minnesota/NW Iowa. I’ve been following FFR since the mid-1990's. I have many old brochures, but somehow lost my original DVD (bummed!). I grew up with the original forum (ffc0bra), and it felt like my second family, despite having never met anyone. Over the years I have built several motorcycles, done car and truck projects, done trackdays, built a 347 stroker, and owned a 2002 Mustang GT for a while that could have been a donor. Still, the FFR seemed like a distant dream; something to be done once I had a nice big shop and the disposable income that this car would require. Nothing stifles a car guy’s enthusiasm like suffering through northern winters, so finally I said enough is enough and moved south. Traded my diesel 4x4 pickup in and bought a new 2017 Mustang GT and started autocrossing it with the local club. During one of those events, who should casually show up for some racing but our own Erik Treves with his recently built FFR Daytona Coupe… and thus, my desire to build a FFR was reignited. Next April I finally placed my order with FFR. Intended usage: Daily driver, HPDE/track, and autocross, drifting, etc. The 2019 season ended with another jacket for winning the regional CAM-C class in my Mustang. Building the Coupe-R and racing a Mustang... Life is good!

June 29th 2019, Stewart calls with the "I'm an hour away" warning. I rushed home from work to receive the car I'd been dreaming about. Including the delivery guy, there were six of us working together to check off the boxes as they came out of the truck, and set the chassis onto a small trailer for transport over the long uphill gravel driveway. Once onto the concrete, we slid the chassis off the trailer and onto a dolly I had built, and pushed the entire thing with all the boxes into the garage.



My chassis was on display at the FFR Open House 2019!







I don't have any sort of deadline for a specific race entry or anything, so it’s not a rush job for me. I prefer to do things right the first time around, with the fewest possible reworks or surprises. As such, I spend as much time researching as I do building…or so it seems. I’ve been accused of over-engineering a lot of things....which is 100% true. Anyway, I’ll make posts to update with pictures and detail my build process until this thread is caught up to my present build status.

Logan’s Gen 3 Coupe-R:
Gen 3 Coupe-R (chassis serial #170)
Gen 3 Coyote (2019 Mustang GT donor engine)
QuickTime bellhousing
Tilton twin-disc clutch
Tilton billet chromoly steel flywheel
Tremec T56 Magnum
IRS with 3.73 Torsen differential
Driveshaft safety loop
Wilwood brakes
Hydraulic handbrake
KRC hydraulic power steering (still intrigued by EPAS/electric)
Shocks TBD (FFR Koni reds for now)
Spring rates TBD (FFR 750F/400R for now)
Swaybars TBD
Front aero (race bumper, canards/dive planes, hood vents, and splitter)
Bottom aero (flat floor, side vents, diffuser)
Rear aero (dual-element wing)
Air jacks with mobile nitrogen setup
Fire suppression
AiM MXP display/logger
Fixed high-back seats
6-point harnesses
Heated seats
Heat and air conditioning
Windshield wipers
Fixed side windows
Carpet
Under 2,900 lbs (hopefully)
305-315 front tires on 11-12” wheels
335-345 rear tires on 12”-13” wheels

[Logan]

June 1st 2019. I have been internally struggling with the decision of engine. Gen 2 Coyote, Gen 3 Coyote, 5.2L Voodoo, 5.2L Aluminator XS, and even (gasp) the LS/LT engine family were under my close scrutiny. My demands were simple: **naturally aspirated**, capable of 500hp to the tires (without race fuel), 7,500+ rpm redline minimum, and <$12,000. The budget wouldn’t allow the mighty 5.2L Aluminator, even though it is the one I wanted the most. Second most desirable was the 5.2L Voodoo (GT350), for the wicked sound of the flat plane crankshaft and 8,250 rpm redline… but the vibrations of the engine are a serious issue. Even Ford struggled with the primary and secondary vibrations of the engine, it likes to shred engine mounts and fatigue any metal parts bolted to it. The tubular space-frame FFR chassis is stout, and I was pondering how to manage the vibrations when I stepped back and realized, the Voodoo isn’t much cheaper than the Aluminator. And the computer requirements are even harder to sort out, because there is no crate-engine application of the Voodoo. Ford wanted to preserve the uniqueness by only offering it in the GT350. Understandable, but unfortunate too. So I chose to table the Voodoo idea… for now.

With the expensive engines eliminated, I was left with Gen 2 or 3 Coyote vs the LS/LT. My 2017 Mustang daily driver and autocross car means I am intimately familiar with the strengths and weaknesses of the Gen 2 coyote. Awesome overall! I raised the 7,000 rpm redline to 8,000. The low end torque, or lack thereof, is one of my few gripes with the car. It is still decent from 2k on up, but I would love an additional 80 lb-ft down low! Turning my attention to the Gen 3 Coyote, direct injection was added but port injection remains. Iron sleeve cylinder liners are gone (saving something like 40 lbs of weight) and replaced with plasma wire spray-arc cylinder liners. Fun fact: this allowed the bore to be increased slightly, meaning this is the first Coyote engine to actually be a true 5 liters, the Gen 1-2 are in the 4.95L area. So less weight and more displacement is good. Anything else? Ah yes, the factory redline was raised to 7,500 rpm and there’s a new intake manifold that out-flows pretty much everything else including the Cobra Jet and Boss 302 manifolds. This manifold is so good, I installed a ported one on my Gen 2 Mustang engine to complement the higher redline. The cost of the Gen 3 Coyote was reasonable too, just under $10k.

The Gen 3 Coyote seems like the clear winner, but there’s still a nagging voice in my head to look into the LS/LT. I’ll admit, I’m a little salty with GM products and the company as a whole, but I can’t overlook their legendary engine family. I refresh myself on their lineup, different generations, crate packages, etc. I had an opportunity to drive a 6th gen Camaro that had the latest 6.2L LT1 backed by a 6-speed TR6060 transmission (similar to a T56). Maybe this specific car had a REALLY dirty air filter, or maybe the heavy chassis was masking the true performance, or maybe I was too used to driving my Mustang? Whatever the reason, it felt lackluster. It drove and revved slowly like a Silverado. My 435hp Coyote seemed to be eager to rev, rushing to redline pulling ever harder as it climbs. The LT1 redline is a low 6,700 rpm, and I expected with 455hp it should at least get there quickly, but overall I left feeling disappointed. The low end torque WAS better than my Mustang, which was welcome, but the engine felt like it would much prefer to lazily cruise around the back roads in a higher gear than to downshift and make music. I’m sure with a few upgrades and a tune it might have come alive, but I don’t want to buy an LS and have to immediately upgrade the cam and entire valvetrain. Surely I could build an LS from scratch just the way I want, but that’s not exactly cheap either and it takes serious time. On top of all this, FFR doesn’t really “support” the LS. Lots of small hurdles to work around by choosing this path. And lastly, it’s sort of taboo to put a GM engine in a Daytona. Yes I know all the stories, Carroll Shelby originally went to GM but they denied him engines, and yes I know Pete Brock designed the body and he has an LS in his personal Daytona to this day, but still. I have decided I am sticking with Ford. ..maybe I should have test driven a Corvette? LOL

So there I was, about a month before my Coupe-R would arrive. I’m on the computer one night when I notice the sidebar with “Suggested Marketplace Items” has a picture of a 2019 Mustang wreck. Click the ad and what do you know…a Gen 3 Coyote for sale, and it’s only 2 hours from my house! Fast forward about a week and the engine has been personally delivered to me at my work! I loaded it onto my trailer pulled by my Mustang, and took it home that afternoon. Wasn’t expecting to buy the engine before the kit arrived, but at half of my engine budget, I would have been stupid to pass it by.

[Logan]

Now, time for inventory. Every nut, bolt, washer, clip, and part was counted. Very few items turned out to be missing, and they were quickly corrected after a call to FFR. POL (Parts Order List) of backordered items was 1.5 pages long, but nothing too major that would stop progress for a while. With the Gen 3 Coyote sitting on an engine stand against the wall, looking at me, I felt for the first time like this was really happening. Well what are you waiting for?! Let the build commence!! First order of business was to remove the body, and put it behind the house until I’m ready for it. Marked and removed all the aluminum panels, and suddenly it’s a bare chassis powdercoated beautiful gloss white, but completely bare naked. I took this opportunity to weigh the chassis because I am technical and my engineering brain demands to know these things. For those like me....the Coupe-R chassis weighs exactly 540 lbs, and I’ve heard various places that the R chassis is around 70-80 lbs heavier than the standard (S) chassis due to the extra tubing. The first part to be officially installed was the steering rack.

[Logan]

Some of the things I intend to do with the car require me to modify or upgrade the FFR supplied parts. Note: this does not mean the stock parts included with the kit are not perfectly acceptable or safe to use, rather I’m expecting to increase the performance of certain areas which means going off the beaten path, when possible. One of the biggest issues I have encountered but am unable to easily correct is with the front spindle and hub. FFR designed their own spindle, and it closely mimics the SN95 (1994-2004) Mustang spindle geometry, except it uses double A-arms instead of struts. The brake caliper mounting holes are dimensioned the same, which means brake kits for those era Mustangs usually* bolt up to the FFR spindle. Normally that’s perfect, as there are a dozen brands making kits for those cars which have been around for a long time. That said, technology has advanced since then, and it would be nice if they would redesign their spindle and hub to S197 (05-14), S550 (15+), or even just beefier custom specs to improve geometry and strength. It could still use standardized brake caliper hole spacing too, so donor brakes or aftermarket stuff like AP Racing or Wilwood can bolt up.

*I say usually because if you go with certain big-brake kits that were designed for the SN95 Mustang, they don’t always bolt right up to the FFR spindle, even though it is SN95 inspired. My spindles had too much material in the webbing at the upper caliper mounts. I had to grind away some of this webbing to allow my Wilwood caliper mounting brackets to fit.





The SN95 wheel bearing is generally fine, and cheap to replace, but it’s on the small side. The S550 wheel bearing is larger and stronger, and still cheap and available anywhere. On top of that, the holes for the wheel studs on the FFR/SN95 hubs are made for 1/2” studs, and the S550 hubs are 14mm (0.55”). FFR tells you to press the larger studs out of the rear hubs (if you have IRS) and supplies smaller 1/2” studs to press in, leaving you with 1/2” studs all the way around. Personally I chose to go the other way. I pressed out the 1/2” studs from the front hubs, and reamed the holes to be a tolerance-fit with the larger 14mm studs, and then pressed those in. Now my car has 14mm studs all around and I can use the same splined lug nuts I use with all my wheels for my 2017 Mustang. Making the best of what I’ve got here.

The spindle itself has a fair amount of flex to it also, as discovered under racing conditions by John George and Mark Dougherty. Their fix was to weld a thick plate of steel on the backside, vertically between ball joints, to brace the spindle from flexing and causing pad-knockback. Before you panic, this was with racing slicks and cornering forces near 2+ G’s...so this is not an issue you’ll encounter while driving your FFR on the street. I will have to wait until I can do my own testing to determine whether I experience this or need to do a similar mod.

With the spindle sorted for now, I focused on the rest of the front suspension. The upper control arms are nice, but as others have found, the rear turnbuckle needs to be shortened slightly to allow maximum caster to be achieved. This is really only desirable if using power steering, which I am. Disassemble the rear turnbuckle and trim the ends of the threaded sleeve. I cut the rounded ends off so only the hexagonal body remained (shortens the sleeve by approximately 1/2”). Then painted and reassembled.





For the rear IRS, cut the knuckles down with a sawzall, flap wheel on a grinder to clean up, and drill the holes out for the larger bolts. Not too bad.



Since I have been autocrossing my S550 Mustang, I have wanted to put taller rear gears in it for a higher top speed in 2nd gear where you spend the entire run. The factory Performance Package Mustangs like mine come with a 3.73 Torsen, which is a great unit, but was limiting my speed. I debated opening my diff and installing a replacement ring and pinion so that I could keep the Torsen inside, but it turned out to be easier and cheaper to swap the entire unit with a complete 3.55 diff I bought on eBay. The 3.55 has Trak-Lok clutch-type discs inside which don't perform quite as well or last as long as the Torsen, but I figured I could always rebuild it later if they wear out. I saved the 3.73 differential just in case, and I'm glad I did! Because about a year later, now I already have a diff for the FFR, and thankfully with the engine, transmission, and tires I was planning to run, the 3.73 ratio would be about perfect. Plus the Torsen gets to go into the FFR! Pure win all around. I painted the differential with POR15, which turned out great, and installed it in the chassis.



Lastly, I wasn't done modifying things enough apparently so I took the FFR leather steering wheel to the pillar drill and created 6 new holes on a standard pattern which will mount to the quick-release I was planning to use. The FFR Moto-Lita pattern is just too unique it isn't really common and makes fitment with other more standardized parts a pain. My solution was to drill the new array of holes split-centered between the existing ones. Easy fix, and works like a charm.

[Logan]

Suspension was all hung loosely for a while, during which time I was drilling the aluminum panels. I took some extra time to fabricate a few extras too. I bought a 4'x6' sheet of slightly thicker aluminum than the FFR supplied panels to make all these parts with, and still have a bunch of it left over. I use Excel to nest the desired pieces using their flat dimensions so that I can minimize waste and maximize the usage of material. I made a cargo box in the rear, to the maximum allowable size limited only by the frame and fuel tank. I still have to make a tri-fold lid for it, which will hinge from the left and hopefully clear the hatch glass when the lid is fully hinged open (can someone take a measurement of the cargo area flat floor to the bottom of the hatch glass at a low point and higher point, then I can draw a line and check?)







Next I fabricated a firewall closeout panel, similar to what others have done before. No reason not to on the Gen 3 chassis. It's perfectly simple to run the fuel lines and wire harness under the bar and just above the bellhousing, no need to have them come out from inside this framework area. You can see my rivnuts for the fuel pressure regulator with reliefs in the aluminum also.



I ran into an issue with the cargo area side panels. I received both of them from FFR, but only one of them had the required bend in the panel. Someone took the right side panel and bent flanges along the perimeter, but forgot to put the big bend in the center so that it actually fits against the chassis bars. I was slightly perturbed, but I figured instead of making them ship a huge aluminum panel replacement to me, I could make the bend myself. Thankfully when they laser cut the aluminum, they leave small diameter holes at the ends of the bend areas. So I used those holes as my line. The problem is, I don't own a metal brake. I could buy one, even the inexpensive 30-inch Harbor Freight one, but with this panel already having flanges on the edges, the panel wouldn't fit in the brake anyway. So I dug out some scrap angle iron and made a very questionable looking but honestly highly effective homemade brake on the edge of a workbench. It took an hour, but the finished panel actually fits WAY better than the left side which FFR bent and shipped with the kit. How ironic, and funny! I considered fixing the bend on the LH panel, but haven't done so yet.

[Logan]

Fuel system has been mocked up. I'll outline my path: I went with the Pro-M Racing fuel pump hanger, which comes highly recommended around here and it's easy to see why. Nice unit, and full flowing supply and return. The latter of which runs to the BOTTOM of the tank...eliminating aeration. Coupled that with a Walbro 255 lph fuel pump, and dropped it in the tank. I had to grind away some material around the locking ring area to get the hanger through the hole. Pro-M sends instructions detailing this, and it's very easy with a rotary tool. Swish some gasoline around in the tank to clear out any metal dust. From the hanger, I used Vibrant Performance -6 AN connectors, with Vibrant -6 PTFE lined hose, into the Trick Flow fuel filter (another highly recommended product). Out of the filter up to the Aeromotive fuel pressure regulator, mounted to the firewall. From the regulator one line goes out to the engine (quick-connector to -6AN adapter clips right onto the fuel rail), and the other line out from the regulator goes back to the Pro-M fuel pump hanger. All the fuel lines are braided stainless steel, PTFE lined, with a black nylon sheath because I think it looks nice and its not nearly as abrasive to nearby components in case it were to rub on anything. No hard-lines means less overall fittings, saving money and giving fewer leak points. They run through the tunnel, because there's really nowhere else for them to go. This is yet another reason (as if you need any additional) to get yourself a driveshaft safety loop. I am fabricating one right now, and will install once I get the driveline in so I know where to mount it.

I also mounted my brake and clutch reservoir. I went with the Tilton 3-chamber full-capacity model with the hose barb ends. If I had to do it again, I'd get the one with AN fittings. The barbs are made for 3/8" hose, and the Wilwood master cylinders are made for 1/4" hose. I ordered Tilton 5/16" hose to split the difference. Took a Herculean effort to get the hose over the barb ends, but finally did. Hose clamps are more for looks at this point...those things will never come loose. I wanted to mount the reservoir in the triangle ahead of the footbox, like the master EdwardB has done, but with the -R chassis there are additional braces in that location that prevent me from doing it. I'm not crazy about the location I chose, but it fits in that area nicely. The front and rear brake circuits will use the chambers furthest forward for easier trackside access, and the clutch will use the chamber closest to the firewall since it will be the least-serviced one.

Oh yeah, I also dropped the engine in... surprise! Actually it has been in and out of the chassis at least 3-4 times by now, but the first time was a big deal at least to me.



It's a rolling chassis! Using my S550 wheels and tires, wrapped in storage tire totes most of the time.



I've also fitted the throttle pedal that was included in the Ford Racing Controls Pack which I got for the Gen 3 Coyote around the holidays. I modified the FFR bracket, originally designed for the Roadster I think but came with my kit, and after much cutting/drilling/fitting/repeating, I came up with a solution. It's flush to the frame-side bracket at the top, but is spaced out over 1" on the bottom, essentially removing the "angle" of the frame-side bracket and giving the pedal a near-vertical surface to mount to. This helps the actuation feel more like you're pressing the pedal away from you in a downward swinging motion, instead of feeling like you're pressing the pedal sort of "uphill". I also shaved the plastic as far as possible while still allowing the electrical connector to clear the steering column. And yes I dug out the wiring harness, located the connector, and clicked it in to check during this entire process. You literally cannot get the S550 pedal mounted ANY higher than I have it, while clearing the steering column with the bearings in the stock FFR locations. I wanted the pedal as long as possible, for maximum resolution... you do not want this to be an ON/OFF switch, especially during an autocross.

[Logan]

Engine mods. I know I said the last thing I wanted to do was buy an engine and have to dump a bunch of money into it or tear it apart and rebuild most/all of it. So buying the Gen 3 Coyote was my way of leaving well enough alone, right? Partially right. The thing is, the Coyote has many strengths and very few weaknesses but the biggest weak link in the engine is the OPG (oil pump gears) and crankshaft sprocket. They're made from powdered metal, and while incredibly strong given their surreal manufacturing technique, they are brittle. If the harmonics are just right, or the load on them is too great, they will crack. If you took one in your hand and dropped it on the concrete, it would break into pieces or shatter. The harder you push the Coyote, the bigger this risk becomes of having them crack inside the engine. High RPM, especially anything over 8,000+ is sure to lead to failure of these parts. Also adding a belt driven supercharger puts additional load on the crankshaft snout, which puts stress onto these parts, and causes them to fail. So it's highly recommended and pretty common in the aftermarket Mustang world to replace these two components with billet steel versions. There are many companies offering billet steel replacements that are an order of magnitude stronger, and can take anything you're capable of throwing at them without breaking a sweat. I picked up a set and installed them in my Gen 3 Coyote as preventative maintenance, so I won't have to worry about them failing while I'm racing at high RPM... or in case I add a supercharger down the road... (hint? Nah. Well, maybe... )





Took the front cover off and dismantled the entire timing system. Lots of chains, pins, bolts, tensioners and guides... it's easy to feel overwhelmed. If you analyze what's here, it becomes easier to understand. There are millions of cars using this kind of timing chain setup, and this one is not so different. Primary chains run from the crank sprocket to the exhaust cams, and then secondary chains run from the exhaust cams to the intake cams. One set just like that per cylinder bank. That's it. A pair of guides and a single tensioner per bank, and that's about all there is to it. The oil pump housing is what we're looking for, and it is between the crank sprocket and the first main cap of the bottom end. Take the housing out of the engine, then split the housing open. Old gears on the left, and new billet gears on the right...covered in assembly lube.



Button up the front end, put the front cover and both valve covers back on, and flip the engine over for the oil pan. I bought the Moroso 20570 that most everyone with a Coyote uses, and a set of their 6mm studs. Using a 2018+/GT350 oil pickup tube makes this easy now (wasn't around when EdwardB was first doing his). The pickup tube is held in place with the Ford windage tray and an O-ring. I would have preferred a mechanical locking feature/bolt, but I suppose the suction of the pump will keep it seated. Plus it can't really go anywhere once the pan is on, so let it be.



With the pan installed, time to work on the back of the engine. I removed the flexplate from the Coyote, since this was originally equipped with a 10-speed automatic in a 2019 Mustang. Installed the Tilton solid billet chromoly steel flywheel with the provided ARP bolts and lube. Then before even thinking about the clutch, I wanted to get the bellhousing installed and fitted. Those of you familiar with dial-indicating a bellhousing for concentricity and parrallelism can attest, it's definitely a process to complete this step. Some guys slap the whole thing together, but Tremec Transmissions and QuickTime bellhousings BOTH specifically tell you to measure the bellhousing before installing. The whole focus is to ensure the input shaft of the transmission will be perfectly inline with the pilot bearing in the back of the crankshaft. You don't want the input shaft pointing off in a direction other than straight forward (parallelism), nor do you want the straight-forward input shaft to be off to one side putting all it's pressure on the 3 o'clock point of the pilot bearing, for example (concentricity). You want them to share the same center point AND direction. I bought my T56 Magnum from Bowler Performance Transmissions, and I picked up their dial indicator plate. Machined large diameter circle, locating pins for the bell, and a flat plane for parallel checking made it a no brainer for $70. The alternative if you do not have this tool is to remove the front cover from your brand new T56 transmission and use that for your measurements. Questionably voiding your warranty (everyone is fuzzy on this), and it's technically less accurate than the Bowler plate because the diameter of circle you're measuring to is less than half the size of their plate. My engine to bellhousing required 0.007" offset dowels to correct, and I'm happy to report that I got down to half the recommended spec. They suggest no more than 0.005" and my measurements were within 0.0025". Perfect! This will make the trans shift as smooth as possible, and keep all the parts happy with no stress from misalignment. I also trimmed the bottom of the bell and block plate flush with the oil pan, and clearanced around the drain plug so I can fit a socket on it instead of just an open end wrench like it was before.

[Logan]

With the bellhousing dial indicated perfectly, it was time to install the clutch. Tilton is a leading manufacturer of racing clutches that can cost more than an entire FFR kit, but they decided to finally enter the street market. They did so with a product that blew the industry away, especially at the price they're asking. I decided to give it a try, so I picked up their new ST-246 twin-disc clutch. Sprung hubs, organic compound, NAS fasteners, billet-aluminum pressure plate (!), extra thick floater plate for thermal mass, it's pretty much top of the spec chart in all categories but the best part is that it costs LESS than some others I was considering which only have stamped steel pressure plates, thin floaters, solid hubs and/or ceramic pucks. Not many driving impressions to be found yet, since it's so new, but the few that have had the chance to drive with it say it feels like magic. Light pedal effort, incredible clamping force, light weight but still retaining inertia, what more could you ask for?? Here it is installed:



Now as awesome as the clutch is, the extra thickness of this setup combined with the relatively shallow depth of the QuickTime RM-8080 bellhousing means there's not much room left for the hydraulic release bearing. I went with the Tilton 6000-Series HRB, and it's as awesome a unit as their clutch. Install is straightforward....usually. But with the space limitations described, I was not prepared for the amount of modification that needed to be done to my brand new T56 Magnum. The pilot tube length is normally a non-issue, but with my limited space I needed to shorten it by over an inch, or it would contact the rear clutch disc before the trans was even seated. I confirmed with Bowler Transmission's service guys that the pilot tube can be shortened. They suggest a pipe cutter so that it can be done with the front cover on. Much micrometer measuring later, I have a shortened pilot tube. Doesn't leave a perfect edge finish, but it's the best I can do without removing the front cover. No room even for my micro-files to fit into the gap between it and the input shaft. Next, the guide pin needed to be recessed into the hole, because the hex portion was keeping the HRB from going all the way to the back of the pilot tube. So I ground down two nubs of cast aluminum from the front cover, and then counterbored the threaded hole to allow the guide pin to recess about 6mm further than before. With ALL of this done, the HRB height was set, and the trans is now ready to be installed on the engine. This is the point that I'm at right now, because I'm waiting to attach the transmission to the bellhousing. I attempted it for about 30 minutes yesterday, but the input shaft wont slide through both clutch discs and engage the pilot bearing, so I think my discs need to be aligned better than the cheap flimsy $8 plastic tool is capable of. I ordered a billet steel alignment tool from Ram Clutches today. It's basically a T56 input shaft with a handle, so I'll loosen the pressure plate and use that to align the discs better, then bolt it back together and hopefully the trans will slide right into place. Twin discs are even more finicky on alignment than single disc clutches, but it can be done and the rewards should pay dividends.





There's only one more post I need to make (air jacks), then the entire build thread will be up to date...

[Logan]

Okay, this next part is just pure racecar. I made it a must-have from the very beginning of my build plan though, and so I am following through. Air jacks.

The FFR Snap-On/Joey Logano Coupe-R uses Allstar Performance air jacks, but they never showed them off or posted pictures of any of the brackets they made. Looking back, I suppose I could have asked nicely to see pics of their brackets, but it's too late now because I fabricated all of my own brackets and welded them to my chassis. I over-engineer things a lot, and I'm a fan of "Overkill is under-rated", so the mounts I made are not particularly light (they weigh a combined total of about 15 lbs) but they are strong enough to lift more than the finished car's weight. I used 3/16"x3" angle iron plus the rings that come with the jacks to fabricate simple upper and lower mounts for each point. I wanted to bolt them to the chassis, but after considering the flex in a bolted joint, and trying to achieve a high enough clamp-load on the fasteners to eliminate said flex but without crushing the tubing they were bolted to, I decided welding would be much better overall. The problem is, I don't own a welder... pretty silly since I've had my welding certification for years. The upshot is I have now confirmed that the rolling chassis fits on a UTV trailer! Lol And thankfully I have friends nearby who are as car crazy as me, and willing to let me borrow their lift and welder on the weekends.

[kd0wda]

Hi Logan,

I noticed in the photo above, the upper control arm is mounted in between those two plates and bolted in place. I discovered in my printed manual (revision 4L, 2019) that there is an additional page added to the end of these steps showing that you install this ABOVE the plate and use two spacers in-between them. Oddly they didn't REMOVE the previous instructions and photos, so I originally installed as you did, then discovered the new page with updated instructions. I'm wondering why the difference? Anyone from FFR shed some light on this? Is this due to some different control arms being provided with newer kits?


IMG_0249.jpg


-Rob

[q4stix]

*edit* Just see edwardb's response below and ignore me

[edwardb]

Hi Logan,

I noticed in the photo above, the upper control arm is mounted in between those two plates and bolted in place. I discovered in my printed manual (revision 4L, 2019) that there is an additional page added to the end of these steps showing that you install this ABOVE the plate and use two spacers in-between them. Oddly they didn't REMOVE the previous instructions and photos, so I originally installed as you did, then discovered the new page with updated instructions. I'm wondering why the difference? Anyone from FFR shed some light on this? Is this due to some different control arms being provided with newer kits?

IMG_0249.jpg

-Rob

The answer is basically in the caption. That top location is if you're using the "race" upper hole locations for the coilovers, which lowers the entire chassis. Or "base" meaning you're using donor Mustang spindles versus the complete kit 2-piece FFR spindles. I would say most typical builds (like this one if you look at the pics) are using the lower coilover holes, the 2-piece spindles, and the UCA between the two plates. Not on top.

[Erik W. Treves]

Also for those of you that don't know... Logan will be using this Coupe R as street driver as well as race... so he is in the S configuration.

[kd0wda]

The answer is basically in the caption. That top location is if you're using the "race" upper hole locations for the coilovers, which lowers the entire chassis. Or "base" meaning you're using donor Mustang spindles versus the complete kit 2-piece FFR spindles. I would say most typical builds (like this one if you look at the pics) are using the lower coilover holes, the 2-piece spindles, and the UCA between the two plates. Not on top.

Thanks for the clarification. I completely misinterpreted the caption to mean that if you had the "R" frame you mount them up there.

[Logan]

EdwardB has it correct. If using the donor spindles, or setting the chassis at Race height, then the upper arms would be above the two plates to maintain suspension geometry. Since you can only get the Coupe-R as a complete kit, it will always have the 2-piece FFR spindles, and never the donor spindles. If I ever move the chassis down but putting the suspension in race height at all four upper coilover bolt locations, I would at that point move the upper control arms to the top of the plates and also probably move the steering rack to the upper hole location also to preserve tie rod geometry.

Erik is also correct, this car will be registered and street driven so I’m starting out using the S height for my chassis. That probably won’t change either, unless I have a big track event where the effort to lower the chassis would be worth it.

[Logan]

I mentioned that I chose Wilwood brakes, but didn't mention that it took months of research after deciding to spec my own custom setup. I wanted to have as many of the same parts as possible for commonality in spare parts (easier to bring one size rotor, caliper, and pads to the track rather than two of everything). I finally settled on the Forged Narrow Superlite 6R in red all around, but with 4.86 sq.in. piston area in front and 4.04 sq.in. piston area in rear. Hopefully the shiny powdercoating doesn't bake off with the high temps... For rotors I have 14x1.25" all around (which limits parking brake options to virtually none), more on that later.



Couple engine updates. The starter that came with my 2019 Mustang engine was a 2-bolt. QuickTime RM-8080 bellhousing requires a 3-bolt. Considered the high-end Powermaster 9532 XS Torque Starter, or the Ford Racing M-11000-C50, but with both of them between $250-300, I passed and went with the more generic 3-bolt starter that has been around for decades in all types of Ford Modular engines. Around $120. Picture shows the 2019 Mustang 2-bolt on the left and the replacement on the right. Yes, it's bigger, but it still fits fine.



I also installed the KRC power steering setup. This includes a bracket, pump assembly, replacement pulley for the water pump with an integrated secondary pulley for the KRC PS, and the belt. Just need to figure out the PS hoses now. If you're going to use the KRC power steering setup, I suggest NOT using the Honda PS fluid that is often highly recommended, instead use the fluid that KRC sells. It is proven to work with their pumps on their pump dynos for hours on end at high temp. Someone had an issue with the Honda fluid, I think EdwardB? I made a note of it and want to pass the tip along.



After those engine bits were finished, I finally got my T56 Magnum trans married to my Coyote. The solution was a $60 billet clutch alignment tool made by Ram Clutches PN 03-048. The cheap plastic clutch tool they throw in for free with any clutch purchase is a nice gesture, but does NOT have tight enough tolerances to keep the clutch (especially my twin disc) perfectly aligned to the pilot bearing. I could get my input shaft to engage the rear disc, but then it would bind every time. After struggling for a while, I ordered the tool like I knew I should have from the start. Sucks pulling the bellhousing back off (with 13+ torqued fasteners), and the pressure plate which had loctite on the 6 torqued fasteners, but it's done now. Everything reinstalled and torqued with the billet tool in place, and the trans slid 97% in with light hand pressure. Gently pulled them together with the bolts around the perimeter, turning each one maybe 90 degrees at a time, mostly overcoming the dowel press fit (there was no bind whatsoever). With that, took off the shifter plate and dropped the whole unit in the chassis!



I have also mounted the A/C Evaporator unit. Yet another item that is made harder because of the -R chassis I have. There is a diagonal bar just above the occupants knees on the drivers side of all Coupes, but on the Coupe-R there is a matching bar on the passenger side. Without that bar, there is room to bring the evaporator into the cockpit another couple inches and makes mounting it fairly straightforward. With the bar there, I had to get REALLY creative in placement. There is literally no other position besides what I have (shown in pics) to fit the unit in a Coupe-R chassis, and even with mine, I'll be making a new outlet panel for the end to move the outlets into the top left corner (3D printed or sheet aluminum).





Despite having less than 2mm of clearance on all sides (seriously this thing is nearly holds itself in place it's wedged in so tight), there is a pocket just ahead of the heater coolant tubes where the blower fan intake is. I hate clutter, and was looking for a way to hide the 4-port heater control switch. Didn't want to put it on top of the footbox back against the firewall because the wiper motor goes there. So I found there is just enough room to install the 4-port switch inside the footbox mounted pretty much directly to the evaporator unit itself. It doesn't obstruct the blower fan intake, and the distance between ports on the switch pretty much lines up directly with the tubes on the evap unit. I will not use the bulkhead fittings (likely not for the AC lines either, I'm just not crazy about them), but will have rubber grommets around each of the 4 hoses. With the light weight of the switch, I'm guessing the short stiff hoses and clamps will be plenty to hold it in place, but if not, I can rivet directly to the switch bracket through the front footbox aluminum.

[Logan]

Continued... Reached 7 pics per post limit.

With the engine and trans in, I was able to measure for my hydraulic handbrake. With rear rotors that are 14x1.25" thick, the options for parking brakes are virtually none. The Wilwood spot caliper (secondary) that FFR sells and many use will not fit the width without machining a spacer, and that's too much work. There are no other cable actuated parking calipers that work on this size rotor either. So, I could use a second full size caliper, or find a way to actuate my existing calipers hydraulically from a second source that isn't the foot pedal. This is where I chose to use a hydraulic handbrake. My choice may have also been influenced by the prospect of doing some light drifting with the car, so a "hydro" as they call it is not an out-of-place addition to a car of this type. The handbrake uses an inline master cylinder in the rear hydraulic circuit. Driver can push the brake pedal like normal, and have all four calipers working normally. Line pressure is unaffected, you'd never know there was anything different. However, when you pull the handle of the handbrake, it actuates the inline master cylinder and applies pressure to the rear calipers only. Release the handle, and everything is normal. Since the handbrake is downstream (closer to the calipers), if you were to push the brake pedal and pull the handbrake at the same time, the handbrake would be the primary force applied (pedal would still be applying force to the front brakes, of course).

I can never seem to take the easy way out, so true to form I plan to mount the hydro under the trans tunnel alongside the T56 transmission. There's very little room to do this, so I had to shop for a couple weeks to find the perfect hydro with the most compact dimensions, and I happened to find it. Oddly enough, they're manufactured just 2 hours away from where I live! As soon as I received it, I fabricated a bracket to mount it. Just needs to be welded in now.



I also took the drill and saw to my Breeze fan shroud. Cut four rectangular slots for the rubber flaps. The point of these flaps is primarily to regain some of the "lost" airflow capacity that the shroud removed by covering some surface area on the back of the radiator. At speed, air pressure will easily open the flaps and allow extra flow beyond what the 16" circle where the fan is can allow. When stopped, the flaps close. When the fan comes on, the negative pressure actually pulls the flaps tightly closed, ensuring all suction is drawing through the radiator. Gotta love simple devices that just work. Once I file the edges of these slots, and drill the three mounting holes per flap, I will paint the shroud and install them.

[P100DHG]

I love the idea of the louvres on the Breeze fan shroud! Great work keep it up!

[Logan]

Since the last update, a couple friends have helped get the ball rolling on the wiring side of things. Car guys around here are getting cabin fever since we have no local racing events going on due to CV19. Plumbing, wiring, and ordering fluids for the first start which has been given a deadline of August 8th, so the clock is ticking!

Items completed:

• Welded clutch pedal stop to footbox, with adjustable elevator bolt
• Finished plumbing air jacks and tested...these are awesome!
• Installed the EVAP unit with 3D printed offset outlet panel installed
• Dynamat heat/vibration and Dynaliner sound proofing installed in footboxes
• Welded driveshaft safety loop in
• Welded mounts for Moroso coolant expansion tank
• Cut trans tunnel for hydro handle pass-through
• Installed battery and fabricated a steel retainer bracket
• Routed and secured various lines and wires in engine bay and footboxes
• Mounted AC condensor and power steering cooler to radiator
• Dash fabricated and bent, working on glovebox now

Other small items complete also, but I don't have time to write out a long post. Here are some pics (I resized smaller than the earlier pics, hopefully these are a better size):

[John Dol]

Great build so far Logan, I like when people go of the beaten path!

John

[Logan]

Beat the deadline for first start by a week! Officially had the engine running on August 1st 2020. Ended up driving it out into the driveway about 40 feet, then backed it right back in the garage and shut it off. No coolant meant I couldn't run for an extended period. I built an oil pre-lube device from an old SBC pump and some fittings. Spun with a drill, I could prime the engine with fresh oil until it was running to the top of the cams on the Gen3 Coyote. Had oil pressure BEFORE the engine was even started which was nice. Fuel pressure set, oil pressure good, power steering primed and nothing leaked. Success!

Some minor tinkering between then and now, but the next report worthy progression was this past weekend. Coolant system filled, seat installed (mostly) and did a true first drive. Total of 3 short trips close to/around the house, put on about 3 miles. Gen3 Coyote needs a tune....bad. In addition to a tune, I made a short punch list of items to complete, and tentatively planned to autocross the go-kart middle of October. We'll see if that pans out. But it would be fun!

I'll see about uploading a video of the first drive here.

[Logan]

[P100DHG]

Love it! Just love the extra touches you’ve done. So clean looking and looks like it runs and drives fantastic. Congratulations

[Rsnake]

Logan, I love your build! Lots of great go fast goodies that I will be using on mine including the brakes.
Congratulations on the test drive, those tires look huge, what size and are those the tires you will be running?
I am still undecided on tires and wheels but love the look of yours.

[Snowman]

Looks great! Glad you made this huge milestone in the build.

[Logan]

P100DHG - Thanks! Of course it’s the extra touches that have kept this project from being finished sooner. Hopefully all worth it in the end.

Rsnake - Thanks! These are actually my autocross wheels and tires for my 2017 Mustang. They will not be the final wheel or tire I use on my Coupe, because I’m hoping to go wider yet. However they work well for the build and go-karting phases. They are 19x11”+50 with 305 RE71Rs squared. Interestingly, I use a spacer in the front of the Mustang, but the rear of the Coupe. Can’t determine fitment to order new wheels until I get the body installed.

Snowman - Thanks! Sure feels good to drive it after so much time building it. Will be even better once I’m racing it!

[Logan]

Been working on exhaust plans for a while. FFR sidepipes aren’t going to work for me for 2 reasons: too loud, and poor flow. I do love the way they look, but that pro doesn’t offset the two cons. The FFR-supplied Coyote headers are actually made by GP Headers. I talked to these guys at PRI 2019 and on top of being genuinely cool people they do beautiful stainless fab work. Note, FFR now offers a ball-and-socket type header that is imported chrome, but not sure if they dropped the GP Headers made stainless ones.

The only thing I don’t like about the GP Headers is the square flange. Looking back, I would have cut it off and welded a V-Band flange to the round area of the merge collector, but I can’t get the pipes off without lifting the engine again and I’m not particularly fond of that so going to work with the square flange for now. My solution is to build a tight-radius 4” round 90-degree elbow, square flange on one end to bolt to the FFR/GP Headers and a V-band flange at the other end. This will be left in place at all times. Then I will have a V-Band connection outside the car at the front of the sidepipe where I can attach various mufflers to. One quiet for tracks with severe noise restrictions, and one open pipe for maximum flow/power/noise.

I am down to sourcing the laser cut flanges now, have everything else to make the elbows and first set of sidepipes. Going with a single 4” round sidepipe for starters, which will probably become my “Quiet Setup” because it’s easy to add baffles to a single 4” round tube.

[only1moreracecaripromiss]

Logan,
Love the input here and detailed information on your project. I'm expecting my coup 65 R kit in May and like you I'm already socking away way too many bits to build this thing. I see that you have the nose dive planes on your list like the Snap On build. Can you tell me where you sourced these as I cant find them on FFR parts list.

[Rsnake]

Logan,
Did you get your wheels ordered yet?

[Logan]

Logan, I see that you have the nose dive planes on your list like the Snap On build. Can you tell me where you sourced these as I can't find them on FFR parts list.

Firstly, congrats on joining the forum and ordering your kit! You used your first post on this forum in my build thread... I am honored. Lol

To your question, the canards (dive planes) are available from FFR. You can call and ask for them, made in their composites shop. A word of warning though, they're not the quality you might expect of a high-end carbon fiber race part from someone like Anderson Composites, APR, Seibon, Speedkore, etc. They're raw carbon straight out of the mold, weave imperfections and fringed edges included. They are NOT clear coated and pretty like what you see on the Snap On car. So expect to do plenty of body work on them (and any other composites received from FFR, the main body included) if you wish to go that way. Had I known, I would have simply made my own. They are not overly difficult shapes even for a beginner.

Logan, Did you get your wheels ordered yet?

Rsnake, I planned to order wheels during Black Friday sales of 2020.... but things were/are tight so didn't place the order. Thank goodness too! Forgestar just released a new wheel profile for the F14 which I will be going with. I was already expecting to be on the extreme end of their available offset on the SDC (Super Deep Concave) wheels, but they have now released a profile called UDC (Ultra Deep Concave) that is available in negative offsets....finally! I will still wait until I put the body on my car to measure for exact fitment. Should be ordering them sometime this Spring though.


Now, update time.

My daily driver 2017 Mustang GT Premium w/ Performance Pack has been a GREAT car, but I knew all along it would be replaced with a truck so I can haul the FFR as needed. So the day after Christmas I drove the Mustang up to Tennessee and traded it in for a 2021 Ram 1500 Big Horn Level 2 Night Edition. Cross the tow vehicle off the list! Now I need a trailer... considering building my own from scratch with a lowering deck that requires no ramps (yes I have a problem).





On the FFR Daytona front....the video a few posts back left out some detail. I had fabricated a bead-forming tool and used it to great success on my aluminum upper radiator tube. Then, ordered the Boig lower aluminum tube after trying half a dozen ways of routing the rubber hoses, with and without a spring inside which tries but doesn't always prevent hose collapse. Plus the amount of hose sticking into the wheel well was too much for comfort, especially considering the amount of wheel and tire I have to stuff in there. Highly recommend the Boig cool tube... nice product and fits perfectly. Filled the Gen3 Coyote with Motorcraft coolant and purged air through the Moroso tank. Just like an OEM Mustang setup, couldn't be simpler. Ran the car for 30 minutes going through multiple radiator fan cycles. All systems looked good. Since then, I have been driving the car here and there. Put about 30 (loud) miles on so far, and need about 100 miles on the clutch for break-in before I can race it. Between this and the tune status, it's the reason I didn't get to race it in 2020. So close!!



During the 30 miles worth of driving, a clunking noise was identified. Turned out to be the bearings I installed in the control arms, one per arm was backwards, so the longitudinal loading caused the retaining rings inside to be forced from their groove, and the captive spherical bearing to move within the shell. Unfortunately, they are easy to press in, but there are no fixturable points with which to press them back out, so I had to weld a tab onto each end to press the incorrectly oriented bearings out and press them in from the other side. As a note, to anyone using bearings in place of the polyurethane bushings... press them all in from the OUTSIDE of the arms, facing in. I had pressed mine all from the same side (from the rear, in my case, all pointing forward). They are all replaced now and solid as a rock, no clunk. Glad to catch that in a test drive before reaching max lateral loading of the chassis mid-corner at an autocross!



I have also been working on seats and harnesses. Believe it or not, this has been one of the hardest parts of my build. Placement, alignment, getting the 6-point harnesses to work with the Kirkeys, sliders for the drivers seat, height with my helmet on, centered to the steering wheel, seat back braces, seat heaters, added side foam (I'm as small as a jockey), and more.... it's been quite the debacle. Getting to a point where they'll work now I hope. Welded some brackets to the bottom of the chassis for the sub straps to bolt into, behind the seat as intended by all racing sanctions.

I also got the last of the exhaust components I spoke about in the previous update, the laser cut flanges. I only needed two, but ended up getting 8 total; 6 plasma cut from stainless steel, and 2 laser cut from mild steel. Once the body is on my chassis, I will fab the custom pipes and hopefully quiet it down some.... many racing organizations have strict noise limits.



Now, I just need to find time to keep working on it! I'm schooling for Mechanical Engineering on the side, and these courses are not easy... I spend more hours sitting at the computer than I get in the garage. Not an excuse, just a factor. I bought HP Tuners MPVI2 and am sort of learning to tune on the side, with help of course... but that's a whole lot of time I don't have right now, so considering calling in some professional help to jump start the process. Lots of other little details over the past few months, but this covers the highlights.

[Snowman]

...Forgestar just released a new wheel profile for the F14 which I will be going with. I was already expecting to be on the extreme end of their available offset on the SDC (Super Deep Concave) wheels, but they have now released a profile called UDC (Ultra Deep Concave) that is available in negative offsets....finally! I will still wait until I put the body on my car to measure for exact fitment. Should be ordering them sometime this Spring though.

Super cool they added another profile! I know I want Foregestar wheels, I really like the CF5. I was going to copy your wheel stud setup and run spacers like you've described, but now I need to rethink that and stare at the F14s more to see if that's the route I want to pursue. I really like the idea of not running spacers, but I do like the look of the CF5 better. Decisions, decisions...

Question: When you drilled your hubs for the ARP wheel studs did you also have to drill out the rears?

[Logan]

I really like the idea of not running spacers, but I do like the look of the CF5 better. Decisions, decisions...

Question: When you drilled your hubs for the ARP wheel studs did you also have to drill out the rears?

I also really like the CF5. I ran that face-style on my Mustang for the past 3 years and absolutely loved them. Classic 5-spoke look, simple yet elegant, easy to clean... On the other hand I also like the look of the F14s, but it pretty much came down to available sizes that made that decision for me. SDC profile and 12" to 13" widths available in the F14, previously with as low as +6 offset, but now with UDC profile they go as low as -50 offset which is nice. I would not hesitate to use a spacer with CF5s or SDC-profile F14s if needed.

As for the hubs, remember the rear hubs (if you go with IRS) are already M14x1.5 studs as they are S550 Mustang spec. FFR would have you replace the beefy M14 rear studs to match their 1/2" studs in the SN95 front hubs... but I prefer to keep the larger of the two. Especially since it's standard issue on many (most) performance cars today. Better clamp load, higher yield strength, handles frequent torque cycles better, etc. To achieve this, you only need to ream out the front SN95 hubs to roughly the size of the rear hubs holes. There's science behind knurl diameter, material displacement, and so on. But long story short, I have done the science and have confirmed results. Buy a 0.612" diameter reamer from McMaster Carr, and within 5 minutes at the drill press you're ready to press in a 0.625" knurl-diameter M14-stud of any length you desire. The reamer is $50, and has little other use besides this, but very much worth it to do it right. Cuts the hub material like butter. Do NOT take a regular twist drill to your hubs!

[Snowman]

I also really like the CF5. I ran that face-style on my Mustang for the past 3 years and absolutely loved them. Classic 5-spoke look, simple yet elegant, easy to clean... On the other hand I also like the look of the F14s, but it pretty much came down to available sizes that made that decision for me. SDC profile and 12" to 13" widths available in the F14, previously with as low as +6 offset, but now with UDC profile they go as low as -50 offset which is nice. I would not hesitate to use a spacer with CF5s or SDC-profile F14s if needed.

As for the hubs, remember the rear hubs (if you go with IRS) are already M14x1.5 studs as they are S550 Mustang spec. FFR would have you replace the beefy M14 rear studs to match their 1/2" studs in the SN95 front hubs... but I prefer to keep the larger of the two. Especially since it's standard issue on many (most) performance cars today. Better clamp load, higher yield strength, handles frequent torque cycles better, etc. To achieve this, you only need to ream out the front SN95 hubs to roughly the size of the rear hubs holes. There's science behind knurl diameter, material displacement, and so on. But long story short, I have done the science and have confirmed results. Buy a 0.612" diameter reamer from McMaster Carr, and within 5 minutes at the drill press you're ready to press in a 0.625" knurl-diameter M14-stud of any length you desire. The reamer is $50, and has little other use besides this, but very much worth it to do it right. Cuts the hub material like butter. Do NOT take a regular twist drill to your hubs!

Thanks for the heads up on the reamer and confirming only the front hubs would need to be reamed out! ARP actually recommends a 39/64 drill bit for their longer S550 wheel studs. The reamer seems like it would be easier to keep the holes centered up.

Still haven't made up my mind yet, I like the sounds of keeping things simple without using spacers on the new F14 profile, but I prefer the look of the CF5. They both look great honestly so i really don't think there is a wrong decision, lol. Ultimately I think I'll let the price of either path guide me. Those ARP studs are NOT cheap! I guess I need to ask Forgestar for quotes and see where that takes me. Plenty of time to get that figured out.

[Logan]

ARP actually recommends a 39/64 drill bit for their longer S550 wheel studs. The reamer seems like it would be easier to keep the holes centered up.

39/64” would leave just over 2 thousandths more material in the holes than the 0.612” reamer I used. Either of those sizes will work just fine, as there is a small allowable range for spline press-fitments. I prefer a reamer to a twist drill because it leaves a perfectly round hole with parallel sides, perpendicular to faces, etc. Machinists use reamers to clean up and perfect the rough hole made by a twist drill. I’m sure you could find a 39/64” reamer too actually.

I agree you can’t go wrong with either the CF5 or the F14. Looks like the UDC profile is about $280 more per set of four ($70 per wheel) compared to the SDC profile, for a given size. UDC is only available in 19” diameter, while F14 SDC and CF5 are both available in 18” if that influences your decision at all?

The ARP 100-7733 studs are about $60 per pack of 5 (There are cheaper options for extended studs, such as Dorman, but not the same strength as ARP). You would only need extended studs if you planned to use a slip-on spacer between 0-1” thick. If you need more than 1” of spacer, you’d be better off using standard length studs and a bolt-on spacer. For track or racing use, a slip-on spacer is preferred to a bolt-on. However, a wheel with the proper offset which requires no spacer is naturally the best method if possible.

[Shakey]

39/64” would leave just over 2 thousandths more material in the holes than the 0.612” reamer I used. Either of those sizes will work just fine, as there is a small allowable range for spline press-fitments. I prefer a reamer to a twist drill because it leaves a perfectly round hole with parallel sides, perpendicular to faces, etc. Machinists use reamers to clean up and perfect the rough hole made by a twist drill. I’m sure you could find a 39/64” reamer too actually.

I agree you can’t go wrong with either the CF5 or the F14. Looks like the UDC profile is about $280 more per set of four ($70 per wheel) compared to the SDC profile, for a given size. UDC is only available in 19” diameter, while F14 SDC and CF5 are both available in 18” if that influences your decision at all?

The ARP 100-7733 studs are about $60 per pack of 5 (There are cheaper options for extended studs, such as Dorman, but not the same strength as ARP). You would only need extended studs if you planned to use a slip-on spacer between 0-1” thick. If you need more than 1” of spacer, you’d be better off using standard length studs and a bolt-on spacer. For track or racing use, a slip-on spacer is preferred to a bolt-on. However, a wheel with the proper offset which requires no spacer is naturally the best method if possible.

Any idea if the Forgestar F14 UDC in a 19in would fit? I'd guess a 325/30r19 tire. I agree it would be great to get a F14 on there with a 315+ width tire and no wheel spacer.

V/R

Shakey

[Logan]

Any idea if the Forgestar F14 UDC in a 19in would fit? I'd guess a 325/30r19 tire. I agree it would be great to get a F14 on there with a 315+ width tire and no wheel spacer.

V/R

Shakey

The wheel itself is just a 19” x 11” or 12” (however wide you choose). Between the SDC profile and UDC profile, you can now get the offset you want built into the wheel so no spacers are required. Even for FFRs where we need low or negative offsets, that’s where the UDC profile comes in.

It’s the tires that are critical for total fitment. Average 18” tire options are 25.5” diameter for 315/30, and 25.9” diameter for 335/30. Moving up to 19” wheels, tires from 315/30 to 325/30 to 345/30 are 26.5” to 27.2” in diameter. So a total of 0.6” to 1.3” taller in diameter, and half of that in radius. The first point of contact with large tires is the short angled square tube of the Coupe chassis behind the seats. Set the wheel offset such that the tire has good clearance to this tube and you should never have any problems. I still really wish they would offer the UDC wheel in 18” as I prefer the tire options there.

[Shakey]

The wheel itself is just a 19” x 11” or 12” (however wide you choose). Between the SDC profile and UDC profile, you can now get the offset you want built into the wheel so no spacers are required. Even for FFRs where we need low or negative offsets, that’s where the UDC profile comes in.

It’s the tires that are critical for total fitment. Average 18” tire options are 25.5” diameter for 315/30, and 25.9” diameter for 335/30. Moving up to 19” wheels, tires from 315/30 to 325/30 to 345/30 are 26.5” to 27.2” in diameter. So a total of 0.6” to 1.3” taller in diameter, and half of that in radius. The first point of contact with large tires is the short angled square tube of the Coupe chassis behind the seats. Set the wheel offset such that the tire has good clearance to this tube and you should never have any problems. I still really wish they would offer the UDC wheel in 18” as I prefer the tire options there.

Thanks for the info. That's good gouge on the angled square tube on the drivers side. I agree that a 325/30r19 is only 1/2 in or so larger than what FFR recommends for the coupe so it should be able to fit in there. I would like to see forgestar expand their lineup because I like a lot of their other designs too but the offsets are soo limiting. If I had my way, I would get a forgestar CF5V in a UDC 18x12 rim with a -25 offset. I guess I'll have to start writing letters to their president.

V/R

Shakey

[Bluemont]

@Logan -

I just ordered my Coupe-R a couple of weeks ago. I just pulled the trigger and ordered my engine and transmission (way early). But it looks like I was able to score a 3.73 torsen rear end with it which I'm excited about. My son is a mechanical engineering student in his junior year and while I'm not really an engineer (Technology career), I really enjoy this stuff. I'll be subscribing to this thread. It is like waiting for the next episode of a TV show. I'm looking forward to seeing how the wheel selection goes. I've been doing a bit of research on that (have my favorites picked out - unfortunately it doesn't look like I'm going to get away without spacers). I'm going to spend the next few months brushing up on my welding skills and working on my other car while I'm waiting for mine to arrive. Anyway, I wanted to drop in on this thread and say I really appreciate the write up that you and so many others on these forums here have done. I'll be shamelessly learning and hoping to remember some of the great advice from these.

[James Morse]

So is the type R for racing only or are you planning to drive on the street with it?

[Logan]

@Bluemont - Congrats on joining the FFR family, and the exclusive -R club! Hopefully you’ve done your research on registering the R-model for street use in your state (sometimes the chassis tubes in the windshield can be an issue). From another thread I see you chose Coyote + T56, and 3.73 IRS. Look forward to following your build. And thanks for subscribing and commenting on my thread. I’ll send you a PM on wheels.

@James Morse - the Coupe-R comes with a serial number and MSO like any other chassis from FFR, but unless you intend to use it on track regularly, there’s many reasons the Street chassis is more preferable. For the Coupe, it’s hard enough to climb in and out of it without the extra door cage of the -R chassis. And as mentioned above, there may be some legal issues from the visibility of having steel tubes in the front windshield area. The street chassis is already extremely stiff, and if you still wanted more you could add basically any of the extra gussets yourself without having to go for the full -R version. Even the Street Coupe chassis has mounts at the rear for the wing...if that’s the consideration. All that said, yes I plan to register mine and drive it on the street, as well as trailer it to tracks with multiple sets of tires. Be careful though, compromise is everywhere... AC doesn’t fit in the -R chassis without a bunch of effort and modding the evaporator, which is just one example.