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Discussion Starter #61 (Edited)
Re: 2008 STi track car Journal

Engine dyno'd at EFI! Success at last!
I tried twice to get the car tuned by Mikey. I was not pleased with his effort. Engine was not tuned with ID 2000's as I wanted. Many engines have been tuned with those injectors!
On 4-12-17 I had it tuned by Calvin Dotson. Calvin knows Subaru motors. He's not just a pure tuner. He goes way back with Cobb. He now commutes and tunes at EFI Logics every other week.
Calvin spent almost four solid hours tuning my car. We finished at 9:30 PM!
We had an oil belching issue at one point. I will be making a few changes in where my bypass valve dumps and have it go directly into the pan. I will soon share my design for an external oil pressure relief valve. The 12mm pump worked well. Oil pressure was 45-80.
Now for the good stuff. I learned from Calvin. The Borg Warner EFR 8374 is a beast on a 2.5 liter engine. Still, the turbo has a good anti-stall area on the compressor intake and I ported it out to the max to take advantage of it. I ran 93 octane pump gas with Torco to give me an effective 107 octane. It turns out I really didn't need that much octane!
When torque really starts climbing it settles out and torque curve almost stays flat! It gets to 350 at 3,700 RPMs and basically stays flat to 7K.
I wanted three tunes/three maps on the SI drive map knob. The base tune is 362 HP/321TQ. The mid-range power level is 431/391. I will probably use this most of the time. I am running 285/295 R compound tires.
The top power map nets 467/391. Calvin smoothed out the power curve a bit so max numbers dropped by about 5 WHP. This on 23.6 PSI!
Calvin is good. He's meticulous. He was focused and did a great job! I can't thank him and Cory and Jack at EFI.
Dyno chart at https://2008subarutrack.shutterfly.com/289
 

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Discussion Starter #63
Have been enjoying the car at the track. Lime Rock was my shakedown day for the engine and car setup. It went well.


Track Day video from Monday, being chased by GTR. Me being chased by a track prepared GTR at Thompson Speedway Motorsports Park, in NE Connecticut, on 5-15-17. In theory the GTR should have been faster. It was not stock.
Was a fun day chasing and being chased. About 140 MPH on the straightaway and my best lap was a 1:22.8, which is 3 seconds off the lap record for TT2. I did not run my full boost map. I kept it at 430 WHP. I'm looking for a little more rear downforce. Plan on raising and adding tilt to the Seibon spoiler.
Next up is Palmer in MA.
 

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Discussion Starter #64
I've now had three track days in the car and it is a blast! I don't even (yet) run it at full power. I am starting to turn respectable ST2 lap times as I clear the cobwebs. Latest Youtube video of a session at Palmer Motorsports Park in MA. This is great little roller-coaster track you should do if you get a chance.
It's about to get five pounds lighter and more aerodynamic with real racing mirrors.
 

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Discussion Starter #65 (Edited)

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Discussion Starter #67
Perhaps now the stock center diff is my weak link in the distribution of power? I can put power down exiting a turn and the rear gets loose first. Somewhat like a rear drive car. It hooks up well and smoothly. I think the rear may have a clunk when I let off hard, yet the diffs work smoothly and quietly.
All I can say is the car is poised, predictable and handles really well. It doesn't do anything funny or act nervous in power transitions.
The diffs may be a somewhat subtle change that's hard to single out with everything else I have been doing to the car, like aero mods and the increase in power. Perhaps if I were to get into a similar car with stock diffs I might say wow, this is crappy.
I don't know if my comments are helpful or not. I know my buddy just installed an OS Giken in his BRZ track car. I think they are quality units. I put mine in so I got to inspect them closely.
 

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Discussion Starter #68 (Edited)
Another track day (@Thompson) and at 467 WHP setting on fresh 285X30 Hoosier A7's. Was a blast and I have no complaints about the diffs or anything. Car was great fun. Classroom instructor called it a beast. Only a handful of faster cars.
Interesting thing is, I am getting an accumulation of about six ounces of thin, oily liquid, smelling strongly of fuel, in my catch can after 90 minutes on the track. There's no water in it. This is apparently what is blown past the A/OS (the part that does not settle and drain back into the engine).
NEW: Dyno data is now up on EFI'd database. 467 WHP on 23 PSI @6,750 RPM! Conservative road race tune.
FYI: I frequently take the engine to 8,000 RPM due to not wanting to shift.
 

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Discussion Starter #69
Re: 2008 STi track car Journal

Nice powerband, that's the way to do it.

Sent from my SM-G935W8 using Tapatalk
If I had it to do again or when I go back into it I would use a larger turbine side. Probably would use the 1.45 (instead of the .92 I have) and open up my downpipe to 3.5" diameter. Perhaps a gate so I could side exit the exhaust on unmuffled track days.
 

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Discussion Starter #71
Four days at The Glen coming up! Note new racing mirrors.

Was chasing and pretty well keeping up with a rare (for the US) $150K+ Exige V6 Cup R.
 

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Yeah looking good. I'm going lapping Saturday, but the weather will be trying. 39*, rain and 20+ mile an hour wind predicted. Plus ice and snow warnings north of the track location which is 12 miles from Lake Michigan. Now I know why I never signed up for this clubs first track outing during previous years.
 

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Discussion Starter #74 (Edited)
Update time?
A cautionary tale.

Just returned from three days at Watkins Glen. On Sunday, I killed the rod bearings in my '07 STi daily driver. I write this to share my experience.

I should know better. I should have had a catch can after the Crawford air/oil separator and not connected the A/OS vent to the intake. As it was, I ran the Crawford's vent back to the cold air intake and my Crawford was not up to the task of dealing with all the oil mist and the frequent high G's. If you do higher G turns that aggravates the oil blowby problems. The head gets loaded with oil and blown out through the vents by crankcase pressure. One solution is KillerB's control valve.
I knew I was getting some oil into the intake so I added a fair amount of Torco to boost the octane, hoping to compensate for the oil from the blowby. I eventually had so much blowby that the car started smoking lightly and I'd get puffs when I shifted. Revving it to 7K, and it running fairly hot, didn't help! WGI is very hard on cars!

I took the DD to WGI because the hard pipe on the race car was cracked at the last minute before loading to go to the track. So, I threw some race pads on it and off I went.

Meanwhile, the '08 has a new turbo. I took the air filter off the car for one session on the track and it ingested a tire marble. That really wreaked havoc on the impeller. You would wonder how tire rubber would get up in that area! I've never found marbles on the engine or even in the engine compartment.
The engine has 45 hours on it and has performed beautifully this season. I will run it one more time at Club Motorsports on October 11th and 12th. Then I'll likely go through it and refresh it.


 

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Discussion Starter #77
Thanks! I am spread a little thin as far as keeping this updated, but I am working on some interesting projects.
Right now I am replacing my FMIC with a rare and new AMR intercooler that has 1,440 CI of cooling. I may put my "no spacer" NA intake and custom fuel rail system on the engine as well as a Boomba throttle body. All in an effort to maximize efficiencies and performance without going up in boost or fuel octane. I am making 467 HP with a stock, semi-closed deck block.
It's a pretty good feat to have a reliable track engine at this level and bumping 8K RPM.
More to come.
 
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