818Rasmus E Modified

[mikeb75]

Your rear firewall mod for the belts is awesome. I'm going to pay you homage when I get to that step

[D Clary]

What kind of paint did you use to touch up the powder coat? After removing the harness bars you kind of need to match better than the seat mounts would need.

[Rasmus]

What kind of paint did you use to touch up the powder coat?

For a brief moment I considered re-powdercoating it, but that's too expensive. Though a powder gun and powder are cheap, the heat lamps I'd need to spot cure powder on a chassis are expensive. Rattle canned it with


VHT Paint Roll Bar & Chassis, Gloss Black.


It looks close. Good enough for a race car.

[longislandwrx]

I don't remember my under seat pan being that big, it's been a while since I looked at it though.

[D Clary]

I was thinking of putting the floor in last to access under the center tunnel and bolting the seats. My seat mounts are similar to yours but 1x2 as I am a little on the short side.

[longislandwrx]

Dclary, I clamped drilled and cleco'd that piece then removed and stored it safely out of the way. I was too worried about dropping a hammer on it. It will be one of the last pieces I rivet in.

[Rasmus]

Dclary, I clamped drilled and cleco'd that piece then removed and stored it safely out of the way.

I did that to the nose floor panel that goes under the battery. Everything's drilled and ready to go; the cross bar in that area is just too good of a jacking point to cover with .040" aluminum and have to worry about bending it.

[Rasmus]

Drilled all the holes for the "under battery tray cover". Didn't install it; the cross bar in that area is just too good of a jacking point to cover with .040" aluminum. Didn't want to worry about bending the aluminum while I'm piecing the car together.


Had to trim down the supplied interior side panel FFR shipped. It was designed for the 818s and didn't fit correctly on my 818r. I'm still a little irked that FFR did't even bother to make interior panels specific to the R's chassis bars and just shipped S panels that don't even fit. Drilled, applied silicon, and riveted both panels to the frame.

[Rasmus]

Well while I was out of touch over the summer the SCCA classified the 818 into E Modified instead of my preferred class of X Prepared. So that's a bummer.

They also moved the Factory Five GTM out of XP and into EM.

[longislandwrx]

Well that's whack. At least...

classified.png

[Rasmus]

Well that's whack. At least...

YEAHHHHHH!

Motor-wise. The case halves returned from Motion Machine. Dale cleaned it up, did a line bore, decked the block back to flat, and opened up my cylinder bores a bit with a hone.


Here's a picture of it at Motion Machine getting ready for the line bore. He had me send him all my case bolts (OEM) and the head bolts (ARP) I intend to use. He torqued everything up to spec before doing anything.
According to Dale:

I recently line bored a block for another shop and when they checked my work they were alarmed that the main bores were .0003" tight in #1 and #5, while the center 3 were at the size or .0001" too big. Then it's perfect I told them. All kidding aside, this is the effect that even stock diameter ARP studs have on the mainline, which is why I line bore all blocks with torque plates attached. They measured the block without plates. The larger the stud and the bigger the torque, the more the distortion. The distortion in size can be easily measured, what cannot be measured is any mis-alignment, which can also adversely affect bearing wear. Here's a picture of a block in the CNC about to get a final pass with the boring tool.

Main Line
Dale had to deck down the case mating faces to get the main line bore to bore straight and true with everything torqued down.


Right half


Left half


Regarding the deck heights:

As I suspected, the decks on your block were all over the place. It was mostly on the right side though, the driver's side was pretty close to the stock height, which is 7.913" However, all virgin blocks will measure 7.912" at #1 cyl, and about 7.908" on the entire right side when the cases are torqued together. So a virgin block measures 7.908" (minus the .0025" I cut for line boring) which means it should measure about 7.905". Your lowest corner was 7.9015". To get the deck surface to clean I had to go to 7.900", and then of course cut the left side to the same height. I don't know your rod length but I think this number is probably right at zero deck or slightly below, seems like most rod/piston/stroke combinations come up at 7.902". The c.d.on these pistons are 1.129" so calculate the total length. Even if it's a couple thou out the hole, it's no problem, but if it's .005" or more, I say we mill the tops of the pistons to get it back to zero. Nothing is easy with motors that have been messed with!

My rods are 134.5mm center to center. +4mm longer than OEM. I'll be running a 75mm stroke crankshaft. The pistons I sent you should have their wrist pins moved up +2 mm from "normal". Because of the -2mm +4mm -2mm math, the piston's heads should extend just as far as an OEM setup.

Your combination will have the pistons out of the deck half a thou, so I'd say we hit it pretty darn close. I was taking half thou cuts on that low side to just barely get rid of left over gasket impressions. Hone is next, I hope to get it down by Friday. Pistons are all exactly the same diameter and I have your main bearings also. I started a thread on NASIOC with a picture of your block, talking about how the 11mm studs affect the main line. Dale

So rather than run an OEM MLS head gasket that's 0.60 mm (?) thick I'll probably end up running a JE Pro Seal 1.00 mm thick MLS head gasket to make up for the deck height decrease and lower the static compression from 8.96:1 to 8.64:1

The cylinder bores were opened up to 3.9270" (99.746mm). Pistons are 3.9235" (99.657mm) diameter when measured 7mm up from the bottom of the skirt. Giving a piston to wall clearance of .0035". Jeremy from JE Pistons recommended the .0035" PTW clearance for my power goals, and this application, with this piston.


Here's a copy of the machine work spec sheet provided to me from Motion Machine.

[Pearldrummer7]

WOW! Looks awesome. What's the total displacement going to be now with your slightly logner rods?

YEAHHHHHH!

[Rasmus]

2.33 liters. Building a long rod, destroker. I'm using 'stroker' pistons that have had their wrist pins moved up 2mm so they can run a 83mm throw crank with stock rods. And instead running +4mm rods and a 75mm throw crank.

[Rasmus]

I need to get the heads down to a machine shop to resurface them. Plus I need to get all the old parts out of them so I can put some new shiny in. So the valves have to come out. So I made my own valve spring removal tool from a pipe my kid found in the desert.


Here's how it looks finished. I intend to chuck it up in the drill press and use the press's mechanical advantage to compress the valve springs. I also made that white topped 'table' to cradle the head. I figure I'll be doing a bit of head work and don't want to mess up the finish. That white top was a cheap HDPE cutting board I bought at a big box store.


How it looks with the head on my cradle and my valve spring removal tool in position.


Close up.

[Rasmus]

The tools I made worked perfect.


Head are all empty and ready to go to the machine shop for a resurfacing. I finally found a shop here in town that has a PCD (polycrystalline diamond) finish insert for their head resurfacing machine. Motor Mission Machine & Radiator. Took a while to fine one. Most shops were like, "Oh ya we do aluminum heads. We'll get it nice and smooth. PCD insert? Nah. We've got CBN (cubic boron nitride). Really nice finish. We've never had a problem with the heads we do. So bring 'em on in!".

"Thanks, man. Will do. Bye."

Contacting Jimmy over at Motor Mission

We do have PCD inserts for the cutting head of our machine but we primarily use CBN.
Our machine is adjustable/variable for the spindle speed, traverse speed, and feed rates in order to achieve a desired finish such as your RA of 10.6.
However, we do not rely on the cutting inserts material make or the machines settings to achieve a specific RA.
In order to do that, we check the surface with our Mitutoyo profilometer whenever we are trying to meet a specific finish.
Once the RA is given by the profilometer we will sometimes hand lap the surface of a head/block by hand as the machined finish will sometimes be on the high side, too rough, and sometimes even on the low side, too smooth.
This is why we charge $75 per head whenever we are surfacing for a specific RA number rather than our normal surfacing charge of $47.50 per head.

When I read that Jimmy could hit a specific target Ra but it would cost a bit more:

Perfect.

I'll bring my heads in on Monday next week.

I also contacted Dale again over at Motion Machine concerning the Ra target I should tell them to shoot for. Dale's spec sheet read that he got the blocks deck surface to 10.6 Ra. He said that 12 Ra or better should be the goal I give them.

Also right out of the Factory Service Manual:
Warp Limit: 0.035 mm (0.0014")
Grinding Limit: 0.300 mm (0.0120")
Standard height of cylinder head: 127.5mm (5.02")

[Rasmus]

Measured the rod journal thicknesses. My micrometer states it's accurate to 0.0001". So I zeroed it up on my 2.0000" gauge block, and got to mic'n.


Journal 1 & 2 results


Journal 3 & 4 results

Journal #2 is the smallest at 2.0470"-2.0471"
Journal #1 is slightly bigger at 2.0470"-2.0471"
Journal #4 is next at 2.0471"-2.0472"
Journal #3 is the fat kid at 2.0472"-2.0473"

The factory service manual states that the limits for a "Standard Size" Rod bearing are 2.0466"—2.0472". So I'm definitely on the upper end of that scale. Which makes sense considered the crank is new and it's been nitrided.


Pulled out the rods so I could measure the big ends' bore sizes. My bore gauge states it's accurate to 0.00005". I labeled each of the rods so I could tell them apart. I zeroed it out in my micrometer which I set to 2.1500" and got to it.


Results. This bore gauge is super touchy. I have to hold my breath. Plus, I can see my heart beating when reading the measurements: "Tha'; +0.01500" ;Thump; +0.01505"; Tha'; +0.01500" ;Thump; +0.01505"

Rods B & C tie for narrowest at 2.1650"
Rod A is next at 2.1651"
Rod D is biggest at 2.1651"-2.16515"

So for a starting pair up without bearings
Rod B and C goes with Journal #2 and #1
Rod A goes with Journal #4
Rod D goes with Journal #3

Next I need to order up a standard size set of rod bearings from King and get to matching

[Rasmus]

Measured the crankshaft's bend. Service Manual limit is 0.0014". My dial gauge's graduations only measure to 0.001", but there's a bit of space between the the graduations so I can read to about 0.00025". Once I zeroed out the dial I couldn't get the dial to read anything else. So either this crank is bent less than 0.00025" or I don't know how to use a dial gauge. I'm gonna go with the former: dead-straight crankshaft.

[longislandwrx]

are you going 1/2 over or 1 on the valves?

[Rasmus]

are you going 1/2 over or 1 on the valves?

Neither. +0. OEM size.


One thing that irks me about the 818R kit is that I paid an extra grand over the 818S kit and I get interior panels that don't fit. So, here we go making panels to get the foot-rest/coolant pass through tunnels to work.


Plus I'm waiting for rod bearings and a whetstone (for piston rings) to arrive so I might as well tackle this. Here's the panel I made.


Got ribbed for bragging how few cleco's I used on my last panel install, so I when full kit-airplane-tarded. Even missed a hole.


Final install.


Tunnel side.

[longislandwrx]

Looks good, I do have a template made for a one piece plate that will cover that whole area, I just have to ask my guy cut it. When I verify fitment I will send it over to all the R boys.

[longislandwrx]

Plus I need to get all the old parts out of them so I can put some new shiny in.

I thought you meant new valves

I think cosworth measured a 50cfm improvement going to +1 valves w/o porting.

IIRC Micah was for the +1s, however your goals are yours and yours alone.

[D Clary]

I have been looking at that piece for a couple of weeks thinking about how to finish it. There are a lot of pieces that came in the kit that don't fit the R model and a lot that could have been included.

[Rasmus]

I thought you meant new valves

Oh, I did. New valves are going in. Just not Subaru's, but Subaru sized. I'm trying to stick by my personal rule not to show pictures of stuff I'm not immediately working on. I've learned to dislike build threads with a long list of parts that never get installed. So I'm trying to be the change I want to see in the world. I'm sure to get to valve lapping here in the new few weeks.

[Rasmus]

Finished the passenger-side footrest/coolant tunnel.

[Rasmus]

Who likes speed holes and has two thumbs?

THIS GUY!


After querying the forum about the purpose of the door hinge mounts on my 818R and getting the answer that they served no purpose.


I removed them.


I had to replate in the missing section but all the new metal I had on hand was too thick for this purpose. I did, however, have some left over metal from my 1968 Cadillac Coupe deVille's rear subframe which was just the perfect thickness. So I cut it up. Ground off the rust and welded it on.


Came out nice. Drilled a few holes. (towel for contrast)


"Drilled" two large holes on the structure to which the front firewall attaches. Passenger side pictured.

Mass-wise:
Less 1352g - Door hinge mounts and a bit of extra bar
Plus 110g - '68 Cadillac end plates
Less 120g - 18 rice-a-riffic speed holes in body mounting tabs
Less 172g - 2 large holes in front firewall structure
Less ???g - metal lost to cut off wheels, grinding, and plasma cutter
Plus ???g - metal gained from welding filler wire

Altogether removed 1.534 kg of mass.

Plus the 818's a little bit Cadillac now.

[Hindsight]

Hahaha, I predict your obsession with weight savings is going to become a running joke in other people's threads (all good natured of course). But I guarantee you'll end up with a finished car below 818kgs while the rest of us are always over. I'm trying not to go over 1900lbs on my S.

[Rasmus]

Hahaha, I predict your obsession with weight savings is going to become a running joke in other people's threads (all good natured of course).

It already has.


It already has.

[Harley818]

Keep up the weight loss program Rasmus,
I'm not going as high as the bar you set for weight loss, but lower weight is good even for us S guys. I've been dieting as much as I can right along. It all adds up as you are continually pointing out.

[Scargo]

More! MORE!!
Good job. Keep it up and thanks for documenting it. Will save me a lot of time...
On the issue of weight: What is the perfect balance (weight bias) for a mid-engined car like this? I know it is wrong-headed thinking, but with past front-engined cars it's always been an effort to shift weight to the rear. With the 818 I think that I should be moving some weight to the front. Not lightening the front at all, but moving things like the battery to the front. In my dreams I see all the cooling in the rear, which will dramatically change the weight bias.

BTW, I was at Lime Rock on Thursday and went out in a friend's '04 STi that is race prepared. He just put the last of the bushings in the rear. He had been putting it off since it requires pulling the rear subframe which requires a complete rear suspension/drivetrain dis-assembly. The car was rotating like a Mo-Fo. Way more than mine. We put the rear sway bar to full-soft and it handled great... as great as a Subie can.
Then I went out in a Lotus Evora S. Though not really faster, it was so composed and smooth and faster through some corners that it unnerved me at the beginning.
I can only imagine what the 818 will be like with 8:1 power rather than the lesser power combined with great handling that I just experienced in the Evora or the heavy, poor handling Sti's.

[nuisance]

OK, no full size windshield for you!

While you're deleting brackets, who knows what this bracket is for?

mystery bracket.jpg

[Rasmus]

If I recall correctly the ideal weight distribution should be around 40:60 (front:rear). I know the high end Solo cars are prepped this way. Weight distribution doesn't tell the whole story though. You also want a low moment of inertia (a.k.a the Flywheel Effect or how difficult it is to turn an object of a given mass). That is, most of the weight lumped at the 40:60 point in the 'center' of the car. Any weight you can move from overhanging past the front or rear axles, the better. Get it all between the axles.

The ideal car layout to get this is a Mid-engined, Rear Wheel Drive car. Which is one of the reasons I purchased this kit.

Of course once you get that low moment of inertia with 40:60 weight distribution you end up with a car that's more than happy to rotate. One that'll snap oversteer if you treat it wrong.

I see all the cooling in the rear, which will dramatically change the weight bias.

So stop thinking about putting that large tank, full of water, 22 inches out behind the rear axle and leave it where Jim Schenck and company designed it: 12 inches out in front of the front axles leaning forward so it's mass is even lower to the ground.

[Rasmus]

While you're deleting brackets, who knows what this bracket is for?

Front Sway Bar Mount. What's it for? CHOPPING!

[Frank818]

40:60 and low moment of inertia is not all. You need good corner weights too and a hell of a great gearbox with perfect ratios. Now we're talking.

[Santiago]

Front Sway Bar Mount. What's it for? CHOPPING!

Yes, yes, and yes!

My kit arrives soon, and that may well be the very first thing I do. Chop that big ugly thing off! I know FFR is considering bringing it back to their mules and testing with it some more, but I figure if ever I wish to consider a front bar, I'm not going to use the Subie part anyway so a scratch built design would be in the works.

Best,
-j

[Hindsight]

Front Sway Bar Mount. What's it for? CHOPPING!

So you aren't running the FSB? Do you think the weight savings will overcome the benefit in cornering/weight transfer or do you just not feel this car needs a FSB? To me, it seems important to have a front bar on a mid-engined car to help transfer more weight to the front during cornering.... at least, that is how I understand it to work. IE in front engine, FWD cars, you often run no front bar, and a huge rear bar to help transfer weight to the rear to even out the tire loading and let the rear tires pitch in their fair share of the work.

[Rasmus]

Yes, yes, and yes!
I know FFR is considering bringing it back to their mules and testing with it some more, but I figure if ever I wish to consider a front bar, I'm not going to use the Subie part anyway so a scratch built design would be in the works.

I saw that same information and hesitated taking a cut off wheel to them. Only reason I could think you want to run a front sway bar would be if you ran a rough track, like Sebring, where you'd need to run softer springs to maintain contact. Without a bar you'd have to run some hella-flush camber up front, sacrificing breaking.

I would like to read the results of FFR's upcoming testing sessions with and without the bar. Then again I should probably just chop.

[Mechie3]

There are lots of pieces of the frame that I always thought could have been cored out for decent weight savings. Its all done on a laser so the labor is zero cost, just a little more time to cut.

[Santiago]

I like to read the results of FFR's testing with the bar. Then again I should probably just chop.

I say chop. But that's just me being rabidly anti-anti-sway bar. =)

What is important to me are the results. Everybody has their own theory about sway bars, most seem deeply confused, but results are a better guide at any rate. The current FFR mules aren't running them. The car is not happy with them on, so what theory are we trying to validate? They're going to test again with the bar on for specific track conditions - this is as it should be. Does the damn thing work or not, if so when and under what conditions? So far it doesn't.

I'm a Mustang guy. When it rains, we disconnect the rear sway bar. Why? You get more grip w/o it. Of course, that's a solid axle car, etc., etc. So is it a direct application of principle? No, but this is what works for us in the real world. We can figure out the correct theory later. Racers have always been this way. Show me the money, talk about it later.

My take: Sway bars are a tuning tool. In the context of the 818, there are a ton of ways to tune the suspension w/o the sway bar. So lose the bar. In theory it creates liabilities while having its advantages, but if those theoretical advantages are just not playing out in the real world, why keep it?

Best,
-j

[Santiago]

Rounded off side of washers to the part. Sharp edges to the bolt. You don't want the sharp edges "digging into" the material of your part.

I'm catching up with your build thread Rasmus!

I'm pretty sure I've read the opposite (need to find the source). The thinking was that the sharp edge is indeed going to dig into something, so you have to decide what's more important to you. Many (most) bolts are not designed with a perfect 90 deg edge between the bolt shaft and the head of the bolt. There's a small fillet that supports the head. When you dig into that with the sharp edge of the fillet you've effectively scored the head, thus creating a stress riser that can lead to the head shearing off.

Putting the rounded edge side of the washer up will more closely match the fillet between the shaft and the head of the bolt. Your part will get scratched, but under a critical application that's the lesser of two evils. Ummm..."structural integrity over beauty?"

Best,
-j

[Rasmus]

I say chop. But that's just me being rabidly anti-anti-sway bar. =)

I'm with you there. Once I read and understood that (anti) sway bars remove traction from the the end of the car they're on, I moved into the same camp. The bigger the bar, the less traction that end of the car will have. For most anything I would ever run, I'll never need a front bar.

I've read and go by the philosophy that you make every attempt to maximize front grip. Then tune the rear's grip to the front to suit your driving style. Adding bar up front means I have to run an even bigger bar in the back. My maximum grip would be even less and the car will weigh more.