Rob T's 818R Build Thread

[Rob T]

I "chickened out" on a track day today at Carolina Motorsports Park based on a rainy weather forecast. I have an open trailer with an open car and none of it is any fun in the rain. There is another day scheduled on 9/18, so I am hoping for better weather. The car was loaded and ready to go. New trans cooler is ready....

On another note, has anyone ever lost the "gauges" on their Cobb Accessport? I went to run the car a few days ago and all of the gauges were blank. I checked the datalogging function and all of the right stuff was still "checked". I wonder if I did something accidentally that blanked all the gauges that normally display. I was able to recreate what I needed, but this was the first time this ever happened.

[Frank818]

Noooooooooooooooo. That sucks!

[Mitch Wright]

Its beautiful here in BG, come on up we have a track day Monday.

[Hobby Racer]

Its beautiful here in BG, come on up we have a track day Monday.

Boy Mitch, if I lived closer I'd have a real problem with my spouse as I'd be there all the time!

[Rob T]

Opted out of the track day today. Hurricane Sally came through and we had rain past midnight last night (2-5" depending where you were). At 7:00 this morning, pavement is still wet. I would have trashed my car towing it at 5:00 this morning on the open trailer.

There are a few upcoming track days. Fingers crossed for good weather. When it is right, it will work out. It's disappointing, but this is a hobby, not my job.....

[Rob T]

Open Throttle Trackdays is running a track day at CMP tomorrow. Guess what? Rain is forecast today and tonight (100% chance) with thunderstorms tomorrow (90% chance). Three track days in September possible, and rain/threat of rain for all.

Fingers crossed for October 9th.

[Frank818]

Man that is unlucky! We are now a week before and the forecast in Woodruff is dry. But rain on Saturday! So hopefully the forecast won't change!

[AZPete]

Ha. Here in the AZ desert the last rain was 103 days ago and that was 0.2 inch! Send some, please.

[Rob T]

I remember it well, with 2 years in NM. Same idea. On the plus side, everything is green here and I am surrounded by trees. Forecast is looking good for Friday, but I'm waiting another day or so to "pull the trigger". I am ready to go....

[Rob T]

Got to the track yesterday. A lot of other people had the same idea. New surface is spectacular. I have to analyze my data still but here are a few highlights. Air temps were mid 60's to mid 70's overcast.

1) I freaked myself out with some "rusty" driving and the car was upsetting on my aggressive upshifts. It felt like something loose in the rear end as the car would "shimmy" a bit. I cut my second session short out of caution and spent lunch checking all the suspension bolts. No issues found.
2) The trans cooler seemed to work well. I need to dig the data out of the system, but the transmission was cooler. The highest IAT I saw was 106F on the AWIC system in the fourth session driving hard.
3) Session 3 was cut short by a crash.
4) I stopped after 4 laps on session 4 because my oil temp was 250F and pressure was down to 50psi or so. Temps were 200 in the first session, 220 in the 3rd session and 250 in the fourth.
5) I skipped the fifth session, which was 40 minutes after session 4 to not risk high oil temps and pressures.

I do have an oil cooler in the back of car above the transmission. It does have fans and has 3" ducts just sitting in each of the side scoops. I am finding that as the car warms and I get more comfortable during the day, I cannot remove the heat from the oil. Water temps are right around 200F, so they are fine. One suggestion was to mount the cooler directly in one of the scoops, which would be easy to do. I am open to other ideas as well. I am running Red Line Race oil (15w-50).

[Frank818]

At least you made it! And back in one piece. I'm glad that time finally happened! When's the next?


106F is very acceptable in IAT, starts to get warm but not too hot. I quickly reach that temp when idling and not moving! Haven't driven hard enough yet to compare but when driving normal in town, at 65F I get 70-72F IAT. Street driving of course.
What AWIC setup you got? Cooler volume, water tank or not, pump power, etc... as long as it was stable across sessions it means it can handle it and not overheat, which is the 1st goal to reach!

At what RPM you got 50psi oil? If it's at idle, that's quite a lot! If it's at 8000, then iiisch....
Are you able to check if your oil flows within specs? Not too quickly and not too slowly?
Were you starting each session at about the same oil temp (apart from session 1 of course)?
How big is your cooler? Maybe it's just too small and keep the same location but use a bigger one. If you redirect air from the scoops through ducts in your cooler, I'm not that sure it would be more efficient by simply relocating it in one of the scoops, in terms of air flow solely.
Maybe you have very hot air around the cooler or that the fans are not pulling the air out efficiently?
Too close to the exhaust?

[Rob T]

A few follow ups

1) My video camera is "dead" and I didn't get any video. I suspect it got killed in the deluge when I was at NCM in July. I never thought to check it because it was always reliable. It's a bummer because I can't link the oil pressure to the rpm like I can when I had video.
2) The oil pressure was around 50psi or so while I was on the track, so at speed. 25 or so at idle, even when the oil was 250.
3) The AWIC has a separate radiator in front of the main radiator and a circulating pump. The line size for the water is 3/4" ID heater hose. I would suspect I get several gallons per minute of circulation. It looks like the water coming back to the AWIC was 85F at it's hottest, so about 15 above ambient, and the IAT was 15-20 above that. This is consistent with what I have seen in the past, but slightly hotter coming back from the radiator due to the load on the system from the transmission cooler.
4) Everything warms up more quickly on subsequent sessions, and I get more confident and push harder. There is a lot of time with WOT or close to it on this track. Also, several sections where I am close to red line.

Some data that I gleaned from my data-logger.

Best lap: 1:52.462, but pretty consistent when there was not any traffic. I got a bit "faster" each session.
Top Speed for the day: 112.66
Braking g's: 0.90
Accelerating g's: 0.71
Left turn g's: 1.59 max
Right turn g's 1.39 max

More to come on the oil cooler as I dig into it a bit. The current location, over the transmission at the very back of the car is tricky. It's hard to duct a lot of air there. I could do much better with the cooler in one of the scoops - more area, and no flow losses. Also close to the oil tank and other piping. As I already have another cooler left, I may just add one more ( I know, extra weight) and see if that solves the problem, before I rip the other one out. That would be relatively easy to do. More to come....

[Frank818]

Rob, I am very happy for you!
Your car is driveable, it WOTs, it redlines, it doesn't leak... when it does those 4 things it means everything else is minor issues. I'm sure you'll fix them in a jiffy.


- I do like your idea of a 2nd oil cooler, that will definately answer your question on that 1st cooler's capabilities/efficient flow. I would do the same for testing purposes. Can't wait to see pix of your setup.


- As for the oil psi, 25 at idle is plenty to me! 50 at speed seems low though, depending what rpm it was at. Basically, you probably know already, psi should increase/decrease with an almost 1.0 correlation with rpm. Maybe 0.9, say. Do you have access to a log that will display RPM vs oil psi? And do you know the std specs for the H4?



As a reference, although I know nothing about the H4, my VR6 runs at 8-8.5psi at 800rpm (freaking low but causes no issues at all) and 75psi at 4000rpm, which is very fine. This is reproducible all the time, give or take 10%. Of course oil temps make psi vary, those numbers I gave are at around 200-210F.

[Mechie3]

WRX engines are known to idle around 12 and run around 80psi at anything over 3000 rpms. Cruising is usually about 30psi,IIRC.

[Rob T]

As I mentioned earlier, I have been suffering from some of the dry sump issues others have talked about. One issue for sure is high oil temp when I am pushing the car hard. This week, I took one of my spare coolers and some -12 line and added a cooler in the driver's side scoop. I also built a a frame and box to mount it and force all of the air through the cooler and into the engine bay. I do not have a sheet metal sheer or a brake, so I made do with some scrap steel, a vice and a hammer. The material was 0.025 aluminum. I re-routed the oil from the discharge of the dry sump pump to the bottom of the new cooler and from the top of the new cooler to the existing cooler in the back. Everything is removeable in case I want to switch it back. I had my first experience with the much revered "CAD" program - Cardboard Aided Design. With decent success. Here are some pics.
The frame on my layout bench
IMG_6310.jpg

"CAD"
IMG_6318.jpg

IMG_6322.jpg
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Plan is to test this on 11/6 at Carolina Motorsports Park if the weather cooperates. I am unable to mimic the condition on the street. More to follow...

[Hobby Racer]

IMG_6322.jpg

I am eager to see your results. I have always wondered if coolers like yours placed at 90 degrees to the incoming air get much airflow.

[Rob T]

I am "hoping" that the scoop will be a higher pressure than the engine bay based on it's direct placement in the slip stream around the car. My old boss said that "hope" was not a strategy. I remember being told this was a high pressure point on the car. That said, that concern is precisely why I sealed around the cooler, so that the only path was through the fins. A lot more work, but should provide better results. I also have aluminum wheel wells....I should know more next Friday.

[Bicyclops]

It wouldn't be that hard to rig some piccolo tubes on the inlet and outlet sides of the oil cooler and run some tubing to an electronic manometer to measure the pressure differential. Taking readings while driving could be a challenge.

Ed Holyoke

[Bob_n_Cincy]

Rob,
Did you read this? Gator finally found the solution to our oil temp and pressure problems.

https://thefactoryfiveforum.com/show...l=1#post430878

[Rob T]

Bob: Yes, Gator and I have spoken. I am trying the cooler first, because it was easy and I had all the stuff I needed making it cheap. I suspect I have oil cooling problems with the cooler in the back.

[Rob T]

Had my track day better. First day with the new cooler in the driver's side scoop. The first three sessions were great, with oil in the 185 range and no pressure issues (85-95psi on track, 35+ in the paddock). The fourth session, I did not upshift in the carousel, a 270 degree tight, high speed that starts with a hard left followed by a continuous right turn onto a high speed straight. When I ran it in 5th, no issues. In 4th, with the RPM's up around 6,000, I started to see some slight pressure drop (55-65psi) and the temp of the oil went to 235. This was better than before, but still remnants of the same problem. I will be working with Gator's help to add the third scavenge line. This only happens under big loads at sustained high RPM's. Driving at 80% or less does not cause this issue. While I don't drive my car on the street, it is safe to say, that it would be unsafe to drive on the street in such a way as to cause this problem.

I did four sessions at CMP. It was crowded because NASA has a race weekend, so many were there. We had up to 50 cars in the run group. A few of the sessions I was fortunate to run near the front and got a couple of clean laps before catching the back of the line. In simple terms, I could easily hang with all the monster camaros and mustangs. I was much better braking and in the turns, but they could pull harder out of the turns. I could keep up on the straights. There were a few GT3RS's there. Could not hang with them. I suspect the car is close to capable enough. The driver is not. Yet.

Here are some quick stats for the day.

Max speed 115.9mph - new high for me on this track.
Max braking: 1.15g
Max Accel: 0.88g
Right Turn: 1.43 g
Left Turn: 1.39G
HP: around 265 Max except last session at 218 - oil in the sump, suspected.
Torque: 300ft-lb

It was a beautiful day with 60-73F temps and a little gusting wind. I'll try to get a video together.

[Sgt.Gator]

Great to see your progress. A 50 car run group, yikes. What tires Brand/Model and Sizes are you running?

[Rob T]

Here are some pics of my dry sump scavenge pump. Reference for all, and a comparison for Sgt.GatorIMG_6335.jpg
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IMG_6340.jpg

[Rob T]

To answer the question about what tires and sizes I am running...

Federal FZ-201, 100 treadwear. Front: 235:40 zr17 Rear: 255:40 zr17. I was targeting 35psi hot, but am interested if anyone else has experience with these tires. At the 35 hot, the "roll" marks on the tire are right at the little imbedded triangle markers....

[Mitch Wright]

Check with Phil at Phil's tire service, I am sure they can give you a operating range. For reference the BFG R1's I ran at 32-34 hot depending on the ambient and track temp. Next time out try a few PSI higher and drop the pressure a few pounds each time out to see what seat of the pants feel and lap times do.

[Rob T]

Quick update on the dry sump.....

1) Thanks to Gator for some extensive conversations and lots of "R&D" work. He's been a big help.
2) Also thanks to John at Aviaid and Phil at Element tuning. I also spoke to Scott at Flatirons. All have been very helpful and interested in this issue as it impacts the "community". John and his team did a great job turning around the order for parts.

So what am I going to do....All agree that there is a scavenge problem at some point, when running hard on the track. There is a lot of discussion of the "whys". I have decided to take a stepwise approach to see if it gets me there. Like Gator, I am adding a third "half section" scavenge pump to the Aviaid pump already in the car. It will tuck in under the manifold, and John had a trick ORB to -8 90 that will fit in there while allowing me to clear the -12 lines already installed. I will begin by plumbing this line to the third scavenge port on the bottom of the pan because it is easy to do. Gator modified his valve covers and I can go there, but will do so, only if needed. I have a track day on 12/5 (weather permitting) that should allow me to test this all out. More to come....

[Rob T]

I started the third scavenge stage install yesterday.
1) Drained all the oil and pulled the filter screen fittings on the pan.
2) Removed the Aviaid pump. The tensioner was a little tricky, so I ended up pulling the mounting bolts and dropping the whole thing so I could work on it on the bench. There are two jam nuts on the shaft, so I think the tensioner is being used as a "pusher" as opposed to a "puller". It works.
3) Rebuilt the dry sump pump and added the third stage. The hardest part was getting the seal out of the end. It had been lock-tighted in. These pumps are truly a precision piece of equipment. Very impressive. It's now all back together with the pulley mounted and spinning freely....ready for re-install and addition of the third scavenge line.

[Sgt.Gator]

For a visual reference here's the one we are installing on the STI this week. It's identical to the one on my 818R. Rob I think yours looks a lot like this, except we used a special hose with builtin ORB fitting to minimize the space requirement.

[Rob T]

Gator: Close to the same except you have a different first stage than I do. Mine enters on the top and exits on the bottom. I did use a special ORB swivel fitting with standard -8 male on the end. Here are some pics. The unit is installed and seems to be working well. The new -8 line heated up more quickly than the -12's, so I know there is oil moving. Looks like rain for the coming Saturday track day, so I need to wait for the forecast to solidify before I sign up.

Original pump configuration with suction lines on the top and discharge line on the bottom of stage one.

IMG_6351.jpg

Oil Pan before installing the new line. You can see the port tucked under the OEM oil feed line. I ran a -8 line from there to the section side of the third pump section

IMG_6343.jpg

Modified pump installed. Internally, all of the discharges are "connected" to a single discharge port in stage 1

IMG_6353.jpg

[Sgt.Gator]

Looks good. Yes I originally had the bottom exit on stage one. I made the change to the side exit a couple of years ago when we rebuilt the pump, it makes it a lot easier to connect up the AN line that runs to the tank.
I need to move somewhere it's not snowing already! But then again the ski slopes are opening so I'll get my Need for Speed.
I'm looking forward to your first track oil data report.

[Rob T]

I did a destructive oil filter test when I was doing all of the dry sump work and had the system drained. Filter was spotless clean. Nothing found.

[Rob T]

Track Day Saturday! 36F to start and 56F for a high. Bright sun forecast after rain tonight. I am looking forward to testing the third stage on the dry sump. More to come. I know the turbo will be making crazy power tomorrow.

[Mitch Wright]

I was just at Road Atlanta yesterday with the same temps and it was a beautiful sunny day. By 10am I just had a sweat shirt on and the track had some grip.
Have fun.

[Hobby Racer]

Track Day Saturday! 36F to start and 56F for a high. Bright sun forecast after rain tonight. I am looking forward to testing the third stage on the dry sump. More to come. I know the turbo will be making crazy power tomorrow.

Remember, we need video or it didn't happen

[Rob T]

AAAAARRRRGGGHGGHHH. I am not going to say that Hobby Racer jinxed me, but the track day did not happen. That doesn't mean that I didn't spend a lot of time in my truck driving to and from the track after getting up at 4:00.

Here's the story. In the end, it boils down to operator (me) error. About 15 minutes from the track, I prepared to stop at a stop sign and it felt like I got hit or my truck mis-shifted. Remember, it's still pitch black outside. I go to the next stop sign about two minutes later. Same thing. This time I get out and take a look at my car. Both straps have fallen off the front wheels. One to the inside and one to the outside. These are on E-track. The over wheel type, which have been absolutely awesome. What kept the car from rolling off the back of the trailer was the little clip and the strap that fell to the inside. But it sure was moving. I got everything hooked back up and went to the track, registered and prepared to unload my car. It started right up....then I thought to my self...maybe I should step on the brake pedal to see if anything bad happened. Yep...right to the floor and fluid all over the trailer where the strap went to the inside. Luckily, they offered my a refund for my registration (CMP is awesome). So I cinched everything down and added an extra strap to the front of the car (the old ones I used to use) and drove home. After unloading, I took a look at the front brakes. On the right side, the -3 fitting to the 18" flex line was sheared off at the caliper. Brake reservoir was empty.

What went wrong....I think I must not have had the straps tight enough or for some reason, the car shifted sideways a bit and loosened one of the straps. Like I said, I've used this arrangement several times with zero issues. Tighter next time.

To add insult to injury, it is 55 with bright sun and light winds today AND I have not validated Gator's dry sump solution yet. It will have to wait until the next track day, which looks like sometime in February, unless they have one in January (a possibility).

Everything happens for a reason...today wasn't my day.

[Sgt.Gator]

Dang! Glad it wasn't worse.

[Frank818]

Really sorry for the bad luck! It happened a few times already, that's enough, bad luck will never happen again starting nnnnnnnnnnnnnow!

[Rob T]

I am not a "life-long" track guy so I am having the "benefit" of cramming a lifetime of lessons and experiences into a few short years. Let's just say the rate of learning is very high. That makes it fun. Most of the time.....

[Rob T]

Check out the General Section of the 818 Forum for some exciting news about a track day at VIR on June 28/29. Hobby Racer and I have been working with Mitch Wright to make this happen. We'd love to see a good turnout. We will be "tagging along" with Mitch's NCM sponsored event. Check out the post....

[Rob T]

I posted a "for sale" item. I have a set of gears from a 5MT for sale(minus the pinion gear). I also have a full 5MT for sale. PM me if interested in either.