Rob T's 818R Build Thread

[Rob T]

Quick Update. Couldn't get in the track day this weekend because I waited too long on a weather forecast - the groups were full. There is another day the second week in March, which I signed up for. While I had the time, I fixed the broken brake line and purged the whole system - back to normal.

I had originally planned to change one thing on the dry sump system at a time, but with the extra "down time" I went ahead and changed the two -12 suction lines from the oil pan to the oil scavenge pump. These are the lines that work under vacuum, along with the oil supply line to the OEM pump. I went with AQP stainless braided hose, which is rated for vacuum. As I suspected (and thought I remembered) Chad has placed flexible stainless steel helixes in these lines to keep them from collapsing. While I believe they did keep the lines from collapsing, they certainly had a negative impact on flow. They don't take up a lot of space, but they make the inside of the tube a much more difficult flow path.

Interestingly, when I run the car in the garage, the -8 suction line heats up the fastest of the three when checked at the inlet to the pump. The -8 is at the front of the engine, is the smallest, and has the "newest" pump. All three lines are moving oil. There could be several reasons why...

1) -8 line is smaller and is a better "straw" for sucking out oil...
2) -8 line is smaller and has less mass, so heats up more quickly
3) -8 line is connected to the newest "half stage" gear pump, so it is more efficient
4) some combination of the above, or something else

The -8 line is not the shortest, so length is not the issue. In the end, I am not sure it makes any difference. The objective of getting more oil flow has been achieved. Now if I could only get my car to the track to verify. Fingers crossed.....

[DSR-3]

5) -8 port is at the front and the engine is tipped forward giving it better supply?
With 3 scavenge ports/pumps, there should be no shortage of capacity. Getting the oil them may be the challenge once you get moving (admit I have 0 boxer experience, but plenty of dry-sump battles!).
Good luck on the project!

[Rob T]

FINALLY - A Great Track Day.

1) Weather was perfect - 55-80F, slightly overcast, a few gusty breezes.
2) THE DRY SUMP ISSUE IS SOLVED - No issues with oiling. This is my first outing with the added "half stage" -8 scavenge line in addition to the two (2) -12 lines originally installed. I also replaced the -12 lines with Aeroquip AQP vacuum rated and removed the springs. Oil pressures were great at all times and oil temps got to 190 in the fourth session. I feel really good about this. I do have two coolers - one is the side pod and one in the back. I am going to leave these for now, as it is only going to get hotter. The engine temp stayed right at 190, on the last session, pushing hard with 80F ambient temp.
3) Car ran all day with massive power. I still have so much to learn, but now feel better about focusing on driving.
4) Trans temps hit 199 - this is with my restricted flow marine cooler tapped into the AWIC line after the AWIC unit. This is actual fluid temp. I have a sensor in the pumped line on the way to the marine cooler.
5) AWIC water, post front radiator was 80-95 F with IAT's in the 99-108 range.
6) I drove 4 sessions.

More to this week when I have time to look at the video and analyze the data.

[Rob T]

Got a chance to pull some data yesterday, but not process all of the video.

Best lap times

Session 1) 1:54.712
Session 2b) 1:53.124 - had to see starter after going off track.
Session 3) 1:54.700
Session 4) 1:55.446

Overall top speed: 110.76
Right turn G's: 1.42 - very consistent in the sessions.
Left turn G's: 1.32 - 1.53
Braking G's: 0.89-0.97
Accelerating G's: 0.65-0.92
Apparent HP Max: 249 - 270 across the sessions.
Apparent TQ Max: 286 - 316

More to come when I have time to do the video.

[Rob T]

Here is a video from one of my best laps (time only defines best). Lots for me to work on, but it was nice not working about oil pressure. More seat time is needed.

Thanks to Mitch Wright, who provided some excellent video coaching (after this day) and gave me some stuff to work on....

https://youtu.be/vZh0PdjC3UM

[Sgt.Gator]

What tires and age/condition?
The best way to learn is to share the car for a day with a better driver. After each session compare data. That how I've upped my game quite a bit by sharing my STI with Retro Racing in enduros. Retro's 3 driver team are multi year class champions in our Conference. I hope to do that again this year with both my 818R and my STI. If Canada and the US will allow them across the border.......
This only works if you have a good data system. I have both AIM and Video Vbox - (Racelogic) in the cars. AIM is great for engine-trans data and ok for driver data. But Video Vbox is still the best for driver development.
I also got a Garmin Catalyst this year but haven't had it on track. I'm not sure it will work in an 818R because the screen will probably wash out in bright sunlight. We'll see. Should be very cool in an enclosed car though.

[Rob T]

Thanks, Gator.

Federal 100 treadwear. Went on the car new on 6/5/20. A total of 19 sessions on 6 different days, but none of the sessions over 20 minutes, because of oiling issues that were a problem until the last session.

I am running a traqmate, which provides pretty good data for the track with GPS and G-sensors, and allows integration with video, as well as 3 analog inputs. Full suite of analytics, segment analysis and comparison, etc.

[Rob T]

Had a track day yesterday. Worked on a few things. Stopped after three sessions. Here's why...

On the way to the track on the third session, I notices a little screeching sound from the left rear, along with a little drag. It was intermittent and timed with the rotation of the wheel. It was very faint. I went out and ran the session and there was no noise when I came back in. An hour later, I was driving to the grid for the fourth session and had the same thing, only a little louder. I did not go do the session, but drove around the paddock a bit, and it seemed to go away. Thoughts range from a sticking piston in a caliper along with a slightly (very slight) out of round disk to something more serious like a failing bearing. It will be a few days before I can get the car on the lift. Any suggestions?

A few other notes: IR temp readings on the hub nut/shaft were identical left and right after session 3. The driver's side rotor measured after session 3 was actually 60 cooler on the left versus the right (I know, not super scientific). No handling issues or noises I could hear on the track. I am wondering if I just got the brakes really good and hot and this was just a bit of pad drag....but wanted to be safe.

Any help would be appreciated. What should I look at and how should I test?

[Hobby Racer]

If you can, take each rear wheel off one at a time and measure the run-out of the disc at the outer edge on the side that faces the pad. You must put the lug nuts on and torque them WITHOUT the wheel on. I usually do this by using regular nuts and washers instead of the conical lug nuts as to not damage the bolt holes on the discs.

You should have similar run out numbers on each side, usually less than 0.005" is good.

[jforand]

I find that there is always a bit of extra resistance when rolling a wheel on everything, It is never perfect and as Hobby said 5 thousands is really no issue, but you will certainly feel that with the wheel in the air and rotating by hand. So if certain conditions exist you could expect to hear it as you did as well.

Not sure of the brakes you are using and where you get them in their operational window, but they can be a tad different (surface wise) rolling back out of the paddock. If you come off hot and park it things can change a bit with the pads/rotor. Without rotation the pads and the covered portion of the rotor cool slower than the exposed portions of the rotor. This can lead to superficial surface variations and some induced warpage issues. Once you get into them again you scrub the surface layer and get them back into the temp window, as well as, even out any temp inconsistencies that might still exist. This effect can be greater as the pads get thinner, they heat quicker and such.

Best way to operate is to keep the rotor in good condition (replace if worn or cracking becomes significant), keep the pad material at least 1/3 of OEM or more, take a cool down spin (minimum to no brakes the last 1/2 lap or so), make sure those wheel lugs are clicked off to the right torque so things can't shift around if the rotor is differentially cooling in the paddock.

It does not sound like a bearing as your temps were tracking other locations, you reported no handling issues, and the sound went away. I assume you had the wheel jacked up and you were tugging on the wheel in several directions to check for a tight bearing.

[Rob T]

Thanks for the feedback. Got the car up in the air. Bearings good. Run out was decent with a total deviation around the outer caliper of 10 thousandths. Interestingly, there was no issue as I took the car off the trailer and moved it to the garage. I suspect Jforand was on to something with the temp and how things cooled. There was no pulsing on the steering wheel at any point during the day or after. Pads are at 95%, so no issue there. Rotors look good. I was braking harder than my "old normal". All suspension components looked good. Ready to hit the track again on 5/21....

[J R Jones]

Rob, A long shot is some type of interference at the axle, CV or even the tire.
If it is coming from the brake, you might try stopping, go to Reverse and stab the brakes. This causes the pads to thrust in the opposite direction and perhaps adjust in the caliper.
Have you inspected the pads for lifting of the friction material? Anti-rattle springs OK?

My race cars always got pushed several times after a session to dissipate caliper heat evenly. The objective was avoid rotor warp from caliper heat soak. 1/3 to 1/2 revolution each push.
BTW if a rear rotor is warped you will feel it in the seat of your pants. Front rotor warp makes the steering wheel shake.
jim

[Rob T]

TRACK DAY - NOT! Need some help.

Today was supposed to be a track day. Got up at 4:00, left at 4:45 and arrived at the track at 6:45, checked in, fired up the car and unloaded it. It was running at idle until I took it to tech about 20 minutes after starting it. Shut it off at tech. Restarted it at tech and drove it back to my paddock spot. About 90 minutes later, and 10 minutes before my first session, I went to start the car. I always turn off the run switch and the main power disconnect. I turned everything on and went to start the car. I don't remember hearing the fuel pump run, which it always does. Tried to start the car....nothing. It turned over briskly and would not start. All gauges were working and I could hear the throttle vane moving, but no fuel pump. Interestingly, the AFR gauge was reading "lean". Missed the first session and went into troubleshooting mode. Looked at all the fuses - all were OK. A couple of guys came over and we tried some stuff with several full power downs and re-starts. Everything came up, but no fuel pump sound. Engine would not fire. So....loaded the car on the trailer with the winch and came home....

Just for grins, I tried starting the car in my driveway after I got home. When I turned on the power switch, the fuel pump cycled and the car started right up. I did it 6 times, with no issues.

I am looking for ideas of what might have caused this. There is nothing worse than a failure like this with a yet unexplained cause. I need to run this down before I head to VIR in a few weeks. It's never happened before...

1) Flakey Fuel pump relay?
2) .....

The car battery is brand new and I have never seen this before.

The rest of the story....I haven't used my winch on my car trailer for the last 8-10 outings. Yesterday, as I was loading the car, I had a premonition to try the winch. It didn't work. The dedicated battery was toast. I ran to Sam's and got a new battery last night, at the last minute. It's odd. Premonition to test the winch, need for the winch today. Maybe God didn't want me on the track today....

BTW - The folks at Carolina Motorsports Park (CMP) are the best. They gave me a credit for the session for next time. They didn't have to, but they did.

[jforand]

Oh man, it seems a few of us registered for VIR are having a stressful last 5 weeks!

I would certainly be looking into the fuel pump relay, the fuel pump power circuit, and the grounds as the starting place. Intermittent failure seems to point to something that changes with movement/vibration like a bad ground or a wire that is shorting to ground if the conditions are correct.

On my first start after dieting and putting in the harness I had no joy on the fuel pump. There is a fuse in the smaller F/B fuse box and it was good. In the end I found that I had cut a conductor that brought power to the relay coil.

Do you have all the wiring diagrams that describe the fuel system wiring? I can shoot you over the ones for the '04 stuff. I have the section Engine Electrical System, Wiring System on the desk right now going after my no start issue. it starts with Page# WI-106. WI-106-108 are very informative for the fuel system.

[J R Jones]

Intermittent, the worst. My guess is a poor connection to the fuel pump or the fuel relay. Consider ignition on, pump disconnected, a test light on the fuel pump power lead, then wiggle the wires/harness and watch for a blink.

[aquillen]

10 years back my '90 Corvette stranded me after putting gas in the tank. An hour later it started like always, at the time I had no clue what was up. Eventually I found out the fuel pump was going bad - one brush in the motor was hanging just enough to not make contact with the motor armature correctly. It would run on one start, then sometimes not on the next try. Pretty sure I remember giving the top of the tank a thump after not hearing the pump prime at ignition on, and then it ran, changed it out then. Tore the motor apart after I changed the pump and I could see the brush was binding in the guide.

[Frank818]

Oh Rob I'm so disappointed!! Again...

I second the others and would check all electrical power to the pump first.
Or even try another one, if you have a spare pump.

Let us know.

[Rob T]

So....I have been going out daily and cycling the main power and the ignition switch to cycle the fuel pump. For two weeks and dozens of tries there were no issues. The other day, I tried and the fuel pump did not cycle. I used that opportunity to swap the Fuel Pump Relay. The pump did not cycle, so it's not the relay. On a whim, I unscrewed the 4 pin Milspec connector that is on the top of the fuel cell that powers the pump and re-tightened it. It was not loose, but the very next attempt, the pump cycled, and has continued to do so at least another 10 times.

Question: Is there any way to make sure the connections in this plug are "secure". The pins are potted in the receptacle on the dry sump. The female bits are in the plug, that also includes the threaded locking ring. The plug is slotted so there is only one way to plug it in. Tolerances for alignment are very tight.

I spoke to Fuelsafe about my issue. According to the person I spoke to, they have never seen an in-tank wiring failure, or issues with pumps other than the filter clogging with degrading tank foam causing fuel starvation. My issue is either the pump cycles or it doesn't. Then at some point, it all works again....

[Sgt.Gator]

Make sure the connections are clean. If for some reason someone used dielectric grease in the connection be sure to clean that stuff out.

[J R Jones]

Rob, In my past with pin/socket connectors, repeated seating (coupling) caused the female socket to get loose. Bending the wrap a bit makes the contact/fit better.
Sometimes the male pin will have a sprung tab on the side that also makes the M/F fit better. I have bent those out to improve contact.
The last pin/socket kit I bought on Amazon was cheap crap, the female socket material was thin and had little tensile strength to maintain contact. Hard to access on line.
jim

[Rob T]

Cleaned the sockets and the pins and re-installed. Car has been 100% reliable since doing that. I have run the car up to temperature(2x) and cycled the fuel pump daily for a few weeks. Fingers crossed for VIR.

[Frank818]

Same VIR event as Hobby?

[Rob T]

Yes...June 28th and 29th.

[Rob T]

It did not go so well for me at VIR. I was able to do three parade laps and 1.5 hot laps before my left rear spindle cracked and the left tire tilted and stopped spinning at 95mph. Luckily, the wheel stayed on the car, trapped by the end of the spindle and the brake caliper. The spindle nut was missing. All we can conclude, was at some point the bearings got a little loose, allowed the spindle to crack, then fail, which then unscrewed the nut, allowing the wheel to come off. Before coming to VIR I had been troubleshooting a slight brake dragging problem on the left rear after being on track. It would go away when the car was cool. I had checked bearing play and run-out before coming here. I never tightened the axle nut, but the dent keeper/indicator was in the right place. Here are some pictures of the damage. The car had to be hoisted off the track because it would not roll. The spindle, and caliper bracket are done, as are the bearings. The inside of the caliper is scored, there is aluminum deposited on the rotor and the inside of the wheel is scored. I am thankful the wheel stayed with the car and there was no apparent body damage or suspension damage.IMG_6651.jpgIMG_6653.jpgIMG_6655.jpgIMG_6656.jpg

[Rob T]

Here is a video of the failure. If you listen carefully, you can hear a big metallic pop at the top of the hill (Oak tree) followed a little while later by a squealing break sound. At speed, I thought the metallic pop was from a rock hitting the fender well. The car did not exhibit any real handling issues until the end....

https://youtu.be/QtJTvcx1oiE

[J R Jones]

Rob, I have been wondering how your event progressed, thanks for the update. The failure was catastrophic but fortunately limited in damage. It would be interesting to see the cracked spindle. You must be questioning the history of that part.
You state the spindle nut came off, I assume you mean the axle nut. That is hard to understand as the axle is splined to the hub, no relative motion.

We had a similar failure running a Mitsubishi EVO in SCCA T2 Nationals. The LR wheel, hub, disc and caliper left the car in Elkhart Lake's Canada Corner at 60(?) MPH.
We determined that the hub retention nut and bearing pre-load were not correct. The axle nut torque was 166 lbft and the bearing play was .002 in. Technician advice was to set the axle torque with the assembly off the ground and spinning the wheel while holding torque on the nut. Theory is the hub bearing balls seat while spin-torquing to make the end play measurement accurate.
Mitsubishi also used a hub/bearing bench test with special fixturing tools to simulate the axle to test bearing breakaway torque (0.74 lb ft) and the spec end play of .002 in.
jim
Rob, to clarify, our axle nut did not come off, the axle broke.
I watched the video a couple times more. Based upon sound and instability, I feel perhaps the nut came off first and the semi-unassembled state cracked the spindle.
Check the spline fit, hub to axle. If the splines are loose they might have worked on the nut to loosen it.

[Rob T]

Lots of theories, but here is what I think happened without doing any more analysis.

1) Last track day at CMP I noticed some brake noise as the left rear tire rolled through the paddock. I aborted the last two sessions and took the car home. I checked run out on the disk while the car was in the air and also tried to "wiggle" the bearings with the wheel on. I went as far as to lower the car almost to the ground and use a long 2X4 to try to get something to move. Nothing did. I remember looking at the axle nut to make sure that the indent was still at the slot. I figured I was good to go. In hindsight, I think the hub was already cracked or the bearings were loose enough to cause issues. However, the brake noise only occurred when the rotors/etc. were hot. Never cold. My assumption at this point was that the caliper piston was a bit "draggy".

2) Monday I did three parade laps at VIR. When I came off the track, there was a slight cyclical rubbing noise on the back left, just like the month before at CMP, but not as severe. By the time I was back to the garage the noise had stopped and it always stopped under braking. I rolled the car in the garage and heard nothing.

3) An hour later I was out for my first session. The loud bang happened after a warm up lap and 1/2 a more spirited lap. At the time, I reconciled the noise I heard to rock bouncing off the aluminum fender well. I never heard the grinding noise from the brake that is evident in the video. I wear ear plugs inside my helmet and my head is right next to the air intake. What I think happened was that the hub was already cracked at CMP a month ago. I think it failed catastrophically at the top of the hill with the sharp right hand turn. Now things that don't normally spin could and I think that unscrewed the nut. I've had 8 track days (multiple sessions per day) since I put those nuts on. A few of the folks at the track suggested that those nuts need to be re-torqued on a regular basis as the bearings wear.

The reason the tire stayed with the car is that the disk was jammed in the caliper and the end of the axle could not pull out of the spindle. The tire got far enough out that it jammed and stopped rotating.

That's what I know for now....more to come after I tear things apart

[Bob_n_Cincy]

This is my spindle that snaped.
stub.jpg
My spindle had been abused in 100s of autocross launches.
It broke during a normal stop at a red light. The nut and spline stayed together and shot out of the side of the car about 6 feet.
My failure was definitely because of rotational fatigue.

I wonder if the heat cycling (expansion/contraction) of the hub and rotor eventually longitudinally fatigued your spindle.
Bob

I'm glad it was just parts, could have been much worse at speed.

[J R Jones]

Rob, Look at everything for leads, like the bearings which may be loose or damaged, they do not wear. You mention "spindle" and "hub" as cracked, I assume that is the upright bearing carrier. If it is a progressive crack, you can inspect crack age by cutting it apart and look at the crack. A dirty section indicates an earlier failure.
Is the outer CV joint OK?
Visualize the things that happen suddenly and things that happen over time.
The bearings can deteriorate over time, and usually get loose and noisy as clearance opens-up.
It is hard to visualize the nut leaving suddenly, unless the threads were pulled-out. That would leave thread debris on the axle threads.
It would take time for the nut to lose clamp load and turn off. I assume there were 10-20 threads engaged. Again, if the splines are OK there is not much rotational movement to loosen the nut.
jim

[J R Jones]

Bob's photo shows the progression of a fracture. It is shiny and dark on the outside circumference and clean in the middle. The break started earlier in the splines. The twisted fragments indicate it was ultimately a (torsional) load failure.

[Frank818]

OMG Rob, you got so lucky not to crash out of control at that speed! How did you manage not to lose control?
That is a serious breakage.

[Rob T]

If you go back to the fourth picture above, you can see where the break happened and the resulting displacement of metal. The axle threads are not damaged and the axle splines appear to be intact. As for the bearing wear/looseness, I think that is possible. However, after my last track session I pushed, prodded, rolled, levered the wheel to see if I could figure out if there was any issues that would cause the brake dragging. While I am not an expert on bearings, there was no apparent looseness, that I could detect nor any sounds....I am not saying that everything was right. I just didn't see or hear anything wrong. More to come...

[C.Plavan]

If you go back to the fourth picture above, you can see where the break happened and the resulting displacement of metal. The axle threads are not damaged and the axle splines appear to be intact. As for the bearing wear/looseness, I think that is possible. However, after my last track session I pushed, prodded, rolled, levered the wheel to see if I could figure out if there was any issues that would cause the brake dragging. While I am not an expert on bearings, there was no apparent looseness, that I could detect nor any sounds....I am not saying that everything was right. I just didn't see or hear anything wrong. More to come...

Ohhh boy. Sorry to hear that Rob. The curse continues dang it. It sounds like a bearing/hub failure if I'm reading everything correctly. Are you sure the axel nut didn't come off first? Technically, you are not supposed to reuse axel nuts on a race car. If you do, make sure to use Red Loctite for piece of mind. I would put bearings on the list to replace every so often to be safe.

Sure you don't want an NP01 ? I'm still just putting oil and gas in it and running it like I stole it for 5+ years.

[J R Jones]

Rob,
Sorry, I did not (do not?) understand the fourth photo.
The fracture shown is the outer portion of the steel hub/bearing carrier, still in the fange?
The attached photo is what it should look like?

If that is the case, the dark portion of the fracture is historic. The 30% clean/bright area is what you ran on this week until the incident.
I would say the fracture started at the 3:30 clock location from fatigue.
How many miles are on this part?
Something was wiggling the inside or the outside of the hub. What was it?
jim

wheel hub.jpg

[Sgt.Gator]

Sure you don't want an NP01 ? I'm still just putting oil and gas in it and running it like I stole it for 5+ years.

Hi Chad! I've been following your posts on the NP01 FB page. I take it you like the "Gen 2" upgrades?

It's taken a long time but I think we've about figured out how to race these 818Rs reliably, despite all of the ones at VIR failing after 2 days!
But yes, I keep up closely with what is happening with the NP01. Unfortunately to have anyone to race against I'd have to do some long travels, there is no NASA in the NW. Anytime you'd like to experience ORP you're welcome to come up here as my guest. I'd love to see your car on track here. We've had 3 members buy Radicals this year, and not the SR3, the SR8 and the one with the Ecoboost twin turbo V6. Crazy fast but they are just as unreliable as any other race car.

[jforand]

Rob, J R makes a great point about the progression. I noticed the color shift, but was not conscious enough to internalize the meaning at the time. The part work hardened over time from the outside in and once hard enough the surface started to crack. That circumferential crack deepened over time and dirt migrated into the fracture (as well as moisture and oxidation) causing the darkening. The non concentric bright metal ring was the last remaining attached material and that is the part that completely failed at VIR this week.

J R, that is not the correct part. That is a more modern design, which Subaru ultimately switched to, but Rob a d I both have the older press through the bearing hub. What Rob has is not a sealed bearing design. He has the two independent roller (or ball) bearings with the outer races pressed into the knuckle and the hubs collar/shaft section (the the wheel flange portion) pressers through those inner races holding the assembly together. The axle nut is torqued to preload the bearings. If the nuts loosen the bearings lose their preload and do not support the load properly causing damage to the bearings themselves. Of course, while the bearings are not properly doing their job holding the hub, it is allowed ‘freedom’ to wiggle about and do bad things, which I firmly believe with result in metal flex, work hardening, and ultimate fracture.

[J R Jones]

Justin, The update design looks good. The older design sounds similar to our Mitsu-EVO. In that case the rolling torque procedure is critical. Look to the bearings, they could have contributed.

[Rob T]

IMG_6668.jpgIMG_6671.jpgIMG_6680.jpgIMG_6683.jpg

Here are some pictures as I disassemble the car.

[Rob T]

The first is a picture of back of the hub. You can see that the fracture happened right on the line with the hub. The second picture is what the axle looked like after I took the tire and broken hub piece off. The third picture is the axle shaft. I "looks" OK to me. The fourth picture is the broken piece of the hub that I pressed out of the knuckle. the piece on the top is the outer bearing seal.

[Rob T]

I'd like your opinions, please. As I already have the "patient on the table". What are your thoughts about replacing the bearings and spindle on the right rear as well? Having the failure at speed was not an experience I'd like to repeat. Looking back, I think I had "warning" with the brakes rubbing slightly after sessions on the Left Rear. I do not have any of that on the right. However, based on the forensic evidence, the crack seems to have been around for a while....I don't know how long it took to manifest itself in either rubbing or a total failure.