Plavan's 818R Build Thread

[C.Plavan]

I tried 0w-40. The problem going lower is oil pressure. You have to keep the oil pressure up running like I do. Not sure I would feel safe going to 30 weight oil, but then again I don't care if the motor blows at this point. Lol

[dirty kurty]

I think you need to focus on what is making the heat rather than how to get rid of it. Have you talked to any Subaru road/rally racers (maybe even try Subaru) to see if this is a common problem? Subaru's GT300 doesn't appear to have as much cooling as your car and they race that thing pretty hard.

Could you try to change your gearing or driving style to keep the revs lower (like 5500?) as much as possible and still keep the lap times down? If I recall your power/torque is pretty flat in at least the ST2(?) tune so this should be possible right?

Before selling the car I would do one of the following:

Best: Tear down the engine and look for problems. Or pull the engine and run it on a dyno and see if you can reproduce the problem and quantify it.

Next best: Run the car on a wheel dyno long enough to make the problem show up and again quantify it for things like revs (does it show up only with long periods at very high revs or can you make it happen at full throttle at 3500-4000rpm).

Quickest: swap the engine out with a loaner (maybe from another 818 owner) or even a running junker (even a junker's engine should last long enough to heat soak the system). I know it's not that easy but it will at least give you a definite answer on whether it is your engine or the application/insufficient cooling.

[Hindsight]

I would be very, very curious to see ECU logs showing timing, fuel, and boost over the course of the last race. My guess is that you'd find something pretty revealing there. Are you logging that stuff?

[bbjones121]

Sorry to hear this Chad.
I know the engine is in the rear on the 818, but the subaru is a world class rally race car. Do they not push cars in a rally race that much or does the engine placement have that much of an impact. I think subaru is even racing in some 24hr lemans races now.

[C.Plavan]

I would be very, very curious to see ECU logs showing timing, fuel, and boost over the course of the last race. My guess is that you'd find something pretty revealing there. Are you logging that stuff?

Yes- it is logged. I'm going to have my tuner look at it again.

[RetroRacing]

My guess is the ecu is retarding timing and over heating the engine. this would answer both the power loss and the oil temp, we see it happen in rotaries every once in a while with a bad knock sensor

[Mechie3]

Did you install the knock sensor? It does have a specific orientation. Local subie guy put his in wrong last week and it caused all sorts of problems.

[C.Plavan]

Did you install the knock sensor? It does have a specific orientation. Local subie guy put his in wrong last week and it caused all sorts of problems.

Motor builder did. I'm going to check it and have tuner decrease the sensitivity. When I had it on the dyno, rocks flying off the Hoosier tires hitting the aluminum splash guard sounded identical to the dreaded ping or knock. Still wonder if that's what happening.

[Frank818]

Is there a reason you are running a knock sensor on a race engine?
I know they are meant for protection, but if they aren't adjusted perfectly, they will trigger while you race.
Anyway, when the sensor kicks in, it's already too late, it knocked. But still it prevents further knocking, depends what you want.

[Doowop]

Chad,

I have been following your thread and I love all the stuff you did on the car. For me you are too close to be done to quit right now. I understand the frustration. I had those racing when you spend $400 in registration on a race weekend and the car ****s on you on the first practice, and you try things, can't figure it out and end up packing all you **** and leave a couple hours later....
I would love to help, and I am thinking that there are enough minds here to be able to help figuring it out. in order to do that and for people to really see where you are, and what you've done, would you be able to put together a little detailed schematic of your oiling system and a list of equipment and things you've done and checked. I think if we had that and had a log of things done, checked, installed we would be in a better position to help, and that might also help you. just an idea....

[Aero STI]

Chad, what about giving Phil Grabow at Element Tuning another call? He is one of the most hardcore small budget road racers in the U.S. Subaru scene. Shipping your motor off to him for evaluation and rebuild would be an option too.

AJW giving you the cold shoulder on engine build questions is the last thing you need when trying to sort this out.

[Sgt.Gator]

Regarding a few folks asking about cooling in Subaru road race cars.....

Subaru road race cars are no more prone to heat issues than any other race car. One auxiliary oil cooler is all they need for the engine oil. Even running an FMIC that restricts and pre-heats the air going thru the radiator doesn't cause any particularly special heat issues. Chad's heat problem is not because of the engine design or some kind of cooling system defect in the production body race cars.

My car back when it was raced in 2006-2007 as part of the Subaru Road Race Team by Phoenix Performance and ICY Racing in the Grand-AM Cup. Despite running 2.5 hour Grand-AM cup races the car had no heat issues. I know this for sure because I have all the logs from where they raced it. One thing to note, they did add an auxiliary oil cooler and also auxiliary transmission and differential coolers, and they DID note high temps in them a couple of times:


The biggest cooling change I've made is a NACA duct to the oil cooler and a heat extractor hood. However these were more for aero reasons than cooling problems. The stock hood has a scoop for the TMIC which is counter productive if you are running a FMIC. So this last winter I fabricated a new hood that adds more front downforce and also cools better:




Which reminds me, if you aren't recording your transmission temps, you should be. I swapped in a 6 speed but tried to run without the trans cooler setup from the 5 speed. It didn't work, I get overheat alarms. I'm in the process of installing the tranny cooler to the 6 speed now. It's a different setup from the 5 speed as far as how it connects to the tranny. If ya'll are interested I can start a new thread in the R forum showing how to plumb the 5 speed (proven setup) and 6 speed (theoretical until I test it).

[Mitch Wright]

Gator,
Looking forward to your write up on the trans coolers. I have been talking to Joe and Andrew at Phoenix Performance (Joe and I drove for the same IMSA team back in the day) Andrew has said the they really didn't have heat issues until they started making over 400hp at the crank. Which they were able to manage by redirecting air through the Rod Davis radiator and adding the additional oil cooler as you have mentioned. BTW they ran a wet sump. Anyway that is I think good news for those of us the are running 250-300whp and running 30-40 minutes, I am still planning a drysump. I don't believe i see the type of heat that would be seen running an enduro. Ok back to work on my car and thanks for the info.

[Sgt.Gator]

Mitch,
VERY COOL that you drove IMSA with Joe! And Andrew has had an incredible couple of seasons winning multiple championships.
I'll put together a post on the tranny cooling setups.

Don't give up Chad! It's nothing like BoostJunkie's thread on NASIOC that has gone on for 5 years now and he has yet to race his car: http://forums.nasioc.com/forums/show....php?t=1921025

[longislandwrx]

here comes some more bad advice... how much time would it take to go back to a standard oil pan and run this on the dyno for 30 minutes straight?

[Mitch Wright]

I drove for Eddie Mecums Camaro Team in 87-88, Joe drove one of the sister cars. I think Andrew had just been born in 88, Joe and I have been friends ever since. I also know Dave Rosenblum really well, I talk to Dave every few months.

[Zach34]

More darts from peanut gallery: If the power loss precedes the oil temp rise, it has to be the tune, right? I mean, look at the oil cooler setup you arrived at for a motor making less than 300 hp - it can't be a cooling issue.

[Mechie3]

Not necessarily the tune. There could be an underlying mechanical issue causing excess heat generation that can be masked to an extent by oil coolers.

[DodgyTim]

I'd have thought a tune (lean) would show up in the water temperature as well (or more so?)
My guess (and it is a guess) is that an oil only temperature rise (given the huge oil cooling system) is related to high oil level in the sump (scavenging/frothing issue for the dry sump) or a bearing issue, maybe made worse by high g turns?

[Zach34]

I'd have thought a tune (lean) would show up in the water temperature as well (or more so?)
My guess (and it is a guess) is that an oil only temperature rise (given the huge oil cooling system) is related to high oil level in the sump (scavenging/frothing issue for the dry sump) or a bearing issue, maybe made worse by high g turns?

Sounds plausible, but why would it wait for 20 minutes before the temp starts to creep?

[DodgyTim]

Sounds plausible, but why would it wait for 20 minutes before the temp starts to creep?

I'd guess ( again ) that it would take some time to beat up the oil or for the oil level to build up in the sump due to insufficient scavenge pump flow rate at high revs
High sump oil level could explain the feeling of power loss too
If no metal is showing up in the oil filter again it would be less likely to be a bearing issue
the dry sump is one of the differences of Chad's build from most others, which might explain why it isn't a more common problem
OR it might be he beats on his car more than others have

[Frank818]

What if you drive the car slowly for 20-30mins, normal street RPMs in the 3-4k range and see if the oil still heats up?

That's an easy test to do!

[Mechie3]

Sounds plausible, but why would it wait for 20 minutes before the temp starts to creep?

Thermal capacity of the system. Same reason it takes 1 minute to boil 1 cup of water in the microwave and 5 minutes to boil 5 cups. With such a huge volume of oil and some cooling there as well it takes longer to reach high temps and/or equilibrium but it will still get there.

[Sgt.Gator]

Sounds like it's time for a Blackstone Lab oil analysis to rule in/out bearing issues.
The analysis may turn up other issues too.
http://www.blackstone-labs.com/

[Wayne Presley]

Chad,
Where is your oil temp sender?

[C.Plavan]

Chad,
Where is your oil temp sender?

Position A. But do say its too close to turbo or in a bad area. It's not the oil sender causing problems, the oil sender works fine and the position is fine per Subi racers. It does not cause the car to lose power.

[Wayne Presley]

A, B, and C are all the wrong position to measure oil temps. I would pick up the temp at the fitting coming back into the motor or in line with the oil cooler return oil. With synthetic oil, I wouldn't have an issue with 265 F°. I think you may be applying air cooled Porsche temp thinking since they are oil cooled as much as air cooled. I think you are chasing a power loss problem that is not oil temp related.

[C.Plavan]

Here is a excel log from the AccessPort. This is from the last session. When you see some 100% throttle position is when I am on the track. I was idling in the pits for a bit. Does anything stand out to you guys?
http://1drv.ms/1f1uFZd

[Sgt.Gator]

Here is a excel log from the AccessPort. This is from the last session. When you see some 100% throttle position is when I am on the track. I was idling in the pits for a bit. Does anything stand out to you guys?
http://1drv.ms/1f1uFZd

I don't know if Sponaugle reads this thread, you might PM him. He would be the one to know.

And to Wayne's point, you can add a oil temp sensor to any of the -12AN lines using this: Allstar Performance Inline Oil Temperature Tees ALL90041 http://www.summitracing.com/parts/AAF-ALL90041 I'm mounting one tonight to monitor the oil temp as it leaves the dry sump tank, headed for the sump.

And this reducer to screw in the 1/8" sender: Aeroquip Reducers, AER-FBM5141, Fitting, Bushing Reducer, Male 1/2 in. NPT to Female 1/8 in. NPT, Aluminum, Black.
http://www.summitracing.com/parts/AER-FBM5141

[Zach34]

Here is a excel log from the AccessPort. This is from the last session. When you see some 100% throttle position is when I am on the track. I was idling in the pits for a bit. Does anything stand out to you guys?
http://1drv.ms/1f1uFZd

I'm as in-the-dark about this as anyone else, but something does stand out. I cut three sections of full-throttle data from the log at 383, 425, and 1085 seconds. The clip at 383 is one of the first stints of full-throttle data, and the clip at 1085 is one of the last. Notice how the ignition timing gradually retarded a total of about 3-4 degrees over the course of the log. Wastegate duty cycles decreased as well despite a slight increase in boost levels - indicating lower cylinder pressures probably from the reduction in ignition advance. All throughout the log are small negative corrections in the "Fine Knock Learn" column. Anybody know what that is? There are a few rare spots of negative numbers in the "Feedback Knock" column, too. Are those numbers cumulative corrections?

https://drive.google.com/file/d/0Bzr...ew?usp=sharing

[Wayne Presley]

What program generated the datalog?

[Sgt.Gator]

It's a Cobb Accessport log.
From Cobb's pdfs on how it works:

Monitor: DAM
What it does: DAM, or Dynamic Advance Multiplier, is a learned correction that adjusts overall timing.
What the numbers mean: For the 02-05 WRX, this number ranges from 0 to 16. For all other turbo model Subarus, this number ranges from 0 to 1 in tenths of a decimal (ex: 0.8). The number advances upwards when no knock is detected and decreases for extreme knock situations. You always want this number to be at it’s maximum value.
Why you monitor it: If you ever see this number decreasing, you have a potential severe knock situation.
What to look for: The starting value will depend on the vehicle and tune, but it should always learn up to the maximum value. This value will reset to it’s starting point after a map Reflash, an ECU reset, or a battery disconnect. If you see this value begin to drop under any other circumstance, you most likely have a severe knock situation. You should immediately analyze the tune and mechanical condition of your vehicle.

Monitor: Fine Knock Learning
What is does: Fine Knock Learning is a learned correction that makes small corrections to timing once the DAM has settled.
What the numbers mean: The values are degrees of timing being added or subtracted. An initial correction is typically -1.4, but is learned away in increments of 0.35.
Why you monitor it: When Fine Knock Learning hits extreme values, the ECU may start to adjust the DAM.
What to look for: Occasionally under low loads you might see an initial knock value followed by several values of that number decreasing in the incremental value (ex: -1.4, -1.05, -0.7, etc). This would mean that the ECU is already learning the correction away, and would be nothing to worry about. These values would also immediately go away after an ECU reset. If the ECU is making consistent and multiple knock corrections under load (such as full throttle and full boost) all in a row, you could have a potential knock situation.

Monitor: Feedback Knock Correction
What it does: Feedback Knock Correction is an instant correction that the ECU applies to timing based on input from the knock sensor and in conditions where the learned corrections of DAM and Fine Knock Learning to not apply.
What the numbers mean: The values are degrees of timing being added or subtracted. An initial correction is typically -1.4 or -2.0 depending on the ECU.
Why you monitor it: Monitoring this can clue you in on instant knock correction.
What to look for: On occasion you might see a few initial correction values pop up under low load situations that do not respond to timing or fuel changes. Just like Fine Knock Learning, consistent and multiple corrections made under high load and not due to sudden throttle changes or shifts can be indications of knock. If you see corrections like this, you should immediately inspect the tune and mechanical condition of your vehicle.

[RetroRacing]

Graph it, much easier I find to correlate cause and effect

[johngeorge]

A, B, and C are all the wrong position to measure oil temps. I would pick up the temp at the fitting coming back into the motor or in line with the oil cooler return oil. With synthetic oil, I wouldn't have an issue with 265 F°. I think you may be applying air cooled Porsche temp thinking since they are oil cooled as much as air cooled. I think you are chasing a power loss problem that is not oil temp related.

Wayne nailed it! oil temps are normal! I regularly see 250deg in my Challenge car and the temperature is in the wet sump oil pan. You can imagine if I measured it at the oil pressure location it would be way hotter!

[Wayne Presley]

It's more that it that the oil is traveling nearly a foot through a heat generator ( the motor) before getting to the sensor and giving a higher reading. When he added the third cooler in clean air and the temps didn't change significantly that told me that not much additional cooling was occurring since the oil was getting close enough to ambient to minimize the heat exchange.

[bstuke]

It's more that it that the oil is traveling nearly a foot through a heat generator ( the motor) before getting to the sensor and giving a higher reading. When he added the third cooler in clean air and the temps didn't change significantly that told me that not much additional cooling was occurring since the oil was getting close enough to ambient to minimize the heat exchange.

Could not have said it better..

[C.Plavan]

This has turned into a crazy thread. I appreciate the help, but people are only reading portions, and not the whole story. Then they think they have the story, and it is not what is happening.

My last run facts:

Oil temps ran at or under 220 degree for 23 min with no problem in race conditions. Once I noticed the power dropping out and looking at the video/data oil went from 220 to 240 degrees in 20 seconds. What sucks, is during this session it did not log on the Accessport, I guess I was too excited and forgot to hit the button. The log I shared above is from the second session, but I was not getting the same power drop off. The car ran at or below 220 for 10 min, then slowly went to 240 then I slowed up when it got to 250ish. Then again, I don't remember feeling the power drop like I did before.

As for the the oil temp sender location I am not at all worried about. Sure I can move it, I might, just to make you crazy people happy. Three suby race shops said it is fine where it is..... but that is not the problem. It is the rapid oil temp climb when I feel the car lose power.

I know what temps I can run synthetic oil at, that's not the main issue. The issue is the power dropping, then temps going up fast. Before I thought the oil temps were causing the drop in performance, but this time the drop in performance happened first, then oil temps went up.

Coolant temp peak was 210
AWIC peak was 136 (post-core)

[C.Plavan]

Could not have said it better..

Do you even have an oil pressure or oil temp gauge? I don't remember seeing one on your car.

[RogerB]

Congrats!! looks like it's going to be an awesome build..

[C.Plavan]

This is the video link once youtube is done processing/uploading.
http://youtu.be/iIuzvtT2aRE