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2008 STi Track Car Journal

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62K views 87 replies 16 participants last post by  Scargo  
#1 · (Edited)

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#43 ·
Re: 2008 STi track car Journal

altspacen said:
What do you have mounted behind your windows leading to the hatch? Are they miniature canards?
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YES! :lol: :busted: Aren't they elegant and don't they make it look more racey? I'm sure they are worth a second a lap. :rolleyes:
It's a joke. I was wondering when someone would say something. Few people have ever said anything about them. Perhaps they think I am crazy. Could be...
They are stick-ons and cost me all of $3.00!
Actually, they have grown on me and I may leave them on there forever.
Should I start a poll of whether to leave them on or take them off?
 
#44 ·
Re: 2008 STi track car Journal

When I first saw them on your car I wondered if they were the stick on fender emblems from autozone that I see on the cars whose owners are of strong hispanic descent. I opted for miniature canards as I thought you happened to come up with something functional for the back half of our cars. =]
 
#59 ·
Re: 2008 STi track car Journal

altspacen said:
When I first saw them on your car I wondered if they were the stick on fender emblems from autozone that I see on the cars whose owners are of strong hispanic descent. I opted for miniature canards as I thought you happened to come up with something functional for the back half of our cars. =]
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I did. Rear spoiler is CF Seibon SKU RS0809SBIMP-STI-S. See post #8.
 
#46 · (Edited)
Re: 2008 STi track car Journal

A taste of what I've been up to. Note HVT recessed camber plates.
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Close-ratio 2006 tranny gets an oil cooler. One like it has on the other side for the Power steering. Can't see the new OS Giken diffs...;) but they're in there!
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One-piece intercooler pipe. Big Setrab oil cooler.
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Oil filter, Mocal thermostatic bypass valve where battery used to be.
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New location for the battery and fire extinguisher. Behind passenger seat which is usually out.
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I now just have gutted headlights; just the outer lenses.
 
#48 ·
Re: 2008 STi track car Journal

Oh, I'm sure it can! External cooling of the transaxle's been done before; just not like I've done it.
The cooler for the power steering: Ditto. Been done before. I've done some things to help airflow around these guys.
I've got a few new things to show off. After I return from PALMER MOTORSPORTS PARK next Friday. New, exciting, roller-coaster, 2.4 mile track.
 
#49 · (Edited)
Re: 2008 STi track car Journal

Should be running in a week!
Finished, clear-coated manifolds. Blue fitting on the far right is where I tapped into the oil fill tube to return oil pressure bypass overflow from Peterson valve. Bypass valve is mostly hidden by the manifold plenum. 12mm ported and modified oil pump has the bypass valve plugged so it cannot open. It also has a deep back plate from an 11mm pump.
Fluidampr crankshaft pulley to dampen harmful harmonics at higher RPMs.
In this shot I am trial fitting the fuel lines and injector rails. I had to switch from the stacked, Boomba design to the Cosworth fuel rails. Now everything clears!
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#52 · (Edited)
Re: 2008 STi track car Journal

EFI Logics has suggested that I might want a "hybrid tune" whereas I was straight speed density on the last motor's tune. I don't know what hybrid implies. Since I am fabbing the CAI and intercooler plumbing for the turbo I still need to know whether I need a straight stretch of CAI to have a MAF in or not.
Note: the answer was that I needed the temp sensor just before the throttle body and the MAF was rendered useless.

While doing the intercooler plumbing, with the mockup motor in place, I ran into clearance issues between the throttle body and my Kaminari carbon fiber, reversed intake hood. I am switching from the 19mm KS Tech phenolic spacer to their 13mm spacer kit. To alleviate fuel rail interference, while retaining the 2002 (?) N/A intake, I used modified Cosworth rails. I added Radium dampers to them. On the intake AVCS solenoid valves, I reworked the brackets that straddle the solenoids (trimming away one side of the saddle-like sheetmetal). Then I countersunk the bracket and changed the 10mm hex-head bolt on top of the bracket to flat-head screws so the head's flush with the bracket.
All this allows me to run the 13mm KS Tech manifold spacer and everything barely clears. The left solenoid connector is the tightest spot. I may need to reposition the MAP sensor off the throttle body.
In hindsight a better solution would be to change the throttle body mounting angle on the manifold or weld on an angled tube to the face of the throttle body.
In another hindsight thought: That would not have solved the interference of the fuel rail and the AVCS solenoid. I do have a solution, but it is not tested yet.
Still, right now with everything mocked-up, it won't quite allow me to get the hood pins in! I cut the hood and create a small "bubble" rather than cutting or machining the manifold plenum area.
 
#53 · (Edited)
Re: 2008 STi track car Journal

Nearing completion of assembly. About all I have to do is mod the engine wiring harness, drop in the engine and add the O2 and EGT gauges to my center console.
I installed dual Oxygen sensors in V-banded down-pipe. One for the ECU and one for me via Autometer gauge.
I did a V-band connections to the 321 SS tubing up-pipe. Modified Full-Race headers are 316 SS pipe. I added shielding film to the K-B oil pan. Pipes will be wrapped. Oil filter is just for break-in, then I will switch to Canton adapter and remote filter and cooler.

Custom turbo mount and custom water line to cool the turbo.

5/8" Silicone waterline for cooling the turbo. The banjo fitting is custom made.

High quality 1/8" Omega thermocouple installed in header. Light flywheel. Custom Killer B oil pan.

Inconel expansion bellows added to Full Race headers. Oil temperature probe and quick-drain valve in K-B high-capacity, racing, oil pan.

A Peterson external relief valve was placed just before the Canton oil filter block and is connected to the pan with a 24" hose.

Plugged return line in the water pump. Crossover tube and heat exchanger/oil cooler are eliminated and a regular blank plug is used in the block.
 
#54 · (Edited)
Re: 2008 STi track car Journal

I will still have hoses from the baffled, 1/2" head vents going to my catch-can which returns oil to the crankcase, but for the larger head breathers and a balance tube between them, I replaced all the rubber hose (shown) with this "T" tube which hugs the case and reduces weight and clutter in the engine compartment.
https://2008subarutrack.shutterfly.com/279
Peterson bypass valve which controls the engine's oil pressure and is easily adjustable, externally was moved off the engine (so the red X)! You can see where the crossover vent tube attaches to the stubby hose and my custom barb is where oil returns to the crankcase from collected blowby. I eliminated the throttle body heating circuit so the nipple is gone fro the water manifold.
I notched the water manifold to clear the SPA oil pressure transducer, installed in the oil gallery on top. It is a strange, less-cluttered landscape. The blue, silicone hose routes the water outlet (which used to go from the water pump to the throttle body) directly to the fill tank.
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#55 ·
Re: 2008 STi track car Journal

I am about a day away from starting the engine. I had to reposition the radiator coolant expansion tank to the rear because the hood wouldn't close with it over the power steering pump. This is a better location anyway.
V-bands are great in so many ways but you bettered get them aligned right or have a flex-coupling. Otherwise they will not fit together and seal. I had a mock-up engine in the car (that I based my exhaust system and turbo location on) but there were some minor variances (probably due to welding warpages) in the fit of the up-pipe, turbo and turbo bracket so that this made the final assembly in the car difficult.
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#57 · (Edited)
Re: 2008 STi track car Journal

UrdnotWrexSTi said:
Mind showing off how you mounted your Setrab oil cooler? And how you placed the air ducts! I'm doing an oil cooler soon but I think I'll add an NACA air duct somewhere on the bumper and use the fog light covers for brake duct cooling
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You might be interested in this, about my first brake cooling mod, before I made the new bumper fascia with the ducts.
You must sign up at Shutterfly but I have a great deal of pictures (and ALL will be revealed if you look at 2008subarutrack.shutterfly.com. There are pictures of the Setrab cooler there.
https://2008subarutrack.shutterfly.com/159
 
#60 · (Edited)
Re: 2008 STi track car Journal

The initial dyno run: Had to install an IAT just before the throttle body so it could be tuned as straight Speed/Density. GM Delphi fast response open sensor #25036751/ACDelco 213-190.
The old, smallish Walbro 255 was not up to the task! A 450 is going in. But at 14 PSI it was making well over 300 WHP! EFI Logic's tuner Mikey Botti thinks it has great potential...
I think in the clip he only took it up to 3K.
With the harsh sound, vibrations and raw intensity of him taking it to 6,000 RPM or more I took two steps back and forgot to record it! :eek:
Dyno video of first run
Update: The Walbro 255 is very marginal for the power I want to make. I actually meant to add an external Walbro 450 with a controller. The fuel starvation was due to goo around the fuel inlet filter. Seems one of my chunks of foam, in the tank, melted. I think I got scammed on Ebay with a piece of foam that wasn't fuel resistant. New 450 is in the tank now.
I'm still waiting for a tune after a couple of failed attempts. It may be that the ID 2000's (2200 CCM) won't get to a low enough pulse width or scale and work with the stock ECU. I thought with my level of build that they would work. Probably would with E85, but I don't want to run it.
ID 1300's are going in. Keeping fingers crossed.
 
#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 105 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 Shutterfly: Photo Books, Cards, Prints, Wall Art, Gifts, Wedding
 
#69 ·
Re: 2008 STi track car Journal

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

Sent from my SM-G935W8 using Tapatalk
Click to expand...
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.
 
#63 ·
Have been enjoying the car at the track. Lime Rock was my shakedown day for the engine and car setup. It went well.

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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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#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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#65 · (Edited)

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#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.
 
#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.
 
#71 ·
Four days at The Glen coming up! Note new racing mirrors.
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Was chasing and pretty well keeping up with a rare (for the US) $150K+ Exige V6 Cup R.
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