GD 04 STi: Stock VF39 333whp/411wtq

04 STi: Stock VF39 331whp/411wtq

Thread must include:
Dyno: Dynojet (Stock STi 230whp/235wtq)
Tuner: Mac Autosport by Nick
Wheel HP: 333whp
Wheel TQ: 411wtq
Ambient Temp: 76 Degrees Faherenheit, 5% Humidity
Elevation: 5,280

Year/Model: 2004 STi
EMS: Opensource Tuning
Short Block: Stock
Heads: Stock
Turbo: IHI VF39
Intercooler: OEM TMIC
Meth Kit: None
Injectors/Fuel: Power Enterprise 850cc Side Feeds, Walbro 255lph Fuel Pump, Ethanol
Intake/Inlet: K&N Short Ram Intake, Stock Inlet
Headers: Stock
Uppipe: Stock
Downpipe: Catted Perrin Divorced Wastegate Downpipe
CBE: Invidia N1 Race 3" Catback Exhaust
Clutch: Stock
Flywheel: Stock
Other Power Mods: TGV Deletes



Tuned on 17.5 PSI on a Forge Manual Boost Controller. Power isn't huge, but very respectable for the psi and the mods on this STi. 300+whp until almost 6500 RPM is nice on the stock snail.

icudruln said:

Thread must include:
Dyno: Dynojet (Stock STi 230whp/235wtq)
Tuner: Mac Autosport by Nick
Wheel HP: 333whp
Wheel TQ: 411wtq
Ambient Temp: 76 Degrees Faherenheit, 5% Humidity
Elevation: 5,280

Year/Model: 2004 STi
EMS: Opensource Tuning
Short Block: Stock
Heads: Stock
Turbo: IHI VF39
Intercooler: OEM TMIC
Meth Kit: None
Injectors/Fuel: Power Enterprise 850cc Side Feeds, Walbro 255lph Fuel Pump, Ethanol
Intake/Inlet: K&N Short Ram Intake, Stock Inlet
Headers: Stock
Uppipe: Stock
Downpipe: Catted Perrin Divorced Wastegate Downpipe
CBE: Invidia N1 Race 3" Catback Exhaust
Clutch: Stock
Flywheel: Stock
Other Power Mods: TGV Deletes

Tuned on 17.5 PSI on a Forge Manual Boost Controller. Power isn't huge, but very respectable for the psi and the mods on this STi. 300+whp until almost 6500 RPM is nice on the stock snail.

Click to expand...

I'll be interested to see what I put down after my tune compared to yours since my build is very similar. Same setup basically; COBB tbe, DW 850cc's, Walboro, ethanol, APS intake, except I wont have the TGV deletes. Nice numbers!!

rek888v2 said:

Nice numbers but I do have to correct something, Stock STi 230whp/235wtq is the stock numbers from a Mustang Dyno which is a load based dyno. The Dyno you got tuned on is a Dyno Jet (Says so on the top of the Dyno Graph) and the stock numbers are around that of what subaru claims as their numbers (300WHP 300WTQ). Not trying to burst your bubble but the truth is the truth.

Still good numbers on that dyno though! AFR's look lean and the HP/TQ curve looks kinda shaky. Id have that checked personally. Your in the 12's at a critical part of the power curve.

Click to expand...

He showed me a few baseline dyno pulls of STi's there, and they were in that 230-240 range (whp). I always thought cars on Dynojet's dyno'ed fairly high as well. I expected a base STi to put down 260ish to the wheels. Honestly, I'm not sure how/what to compare it to in terms of other car's dyno graphs. :|

In regards to the dyno graph, that's how I've seen dyno graphs from Dyno Jets. I've never been definite on the AFR curve, since I've never fully understood the stych ratio of E85, and translating that to a correct AFR ratio from that graph. I'd love for someone to explain it in more simple terms than I've heard.

FWIW, the best runs I've had against Subaru's were these (no idea on numbers they put down):
1. 18G STi on pump gas, basic supporting mods. Dead even from a 40-80 roll.
2. Stage 2 + intake and ported heads GD STi. Good friend of mine. Pull it by 2 cars.
3. GR 2010 WRX. Pump gas FP Green + FMIC, CAI, TBE, Injectors. Pulled me by a car.

See what I mean by not knowing what to compare it to? :lol:

rek888v2 said:

Nice numbers but I do have to correct something, Stock STi 230whp/235wtq is the stock numbers from a Mustang Dyno which is a load based dyno. The Dyno you got tuned on is a Dyno Jet (Says so on the top of the Dyno Graph) and the stock numbers are around that of what subaru claims as their numbers (300WHP 300WTQ). Not trying to burst your bubble but the truth is the truth.

Still good numbers on that dyno though! AFR's look lean and the HP/TQ curve looks kinda shaky. Id have that checked personally. Your in the 12's at a critical part of the power curve.

Click to expand...

rek888v2 said:

Thats impossiable. The dynograph numbers you saw are those of a mustang dyno. I promice you that.

Click to expand...

Sorry bro but you're wrong. I've NEVER I say again NEVER seen ANY stock Subaru dyno 300whp/300wtq. Mustangs usually put GD's at 190-230whp. DynoJet's are usually 230-240 like what icudruln said. GR's are a little more maybe 250ish and the new 2011's are around 255whp DynoJet. What you're saying is a stock 300/300 (crank power) car has ZERO drivetrain loss? Not trying to be a dick but if you can send me a link via pm to a dyno reading a bone stock sti 300/300 I'll eat my words.

I do agree that you're AFR's look lean. People running e85 are usually around 9-10:1 not 11-12:1, that's what you should be at on 93oct. The numbers you're making are good and normal....if you're at sea level!! I too would take some logs and have it checked. A buddy at Ft. Hood had a stg2+ sti on E85 and made about 330/410 (something like that) and he ran the piss out of it...his motor popped. A ring let go. Mind you that was at sea level too with that power.

Damn thats nice.. I should look into doing a few more mods!

Wow, a lot of misinformation in this thread. I searched a bit to find a thread somewhere about your car because I saw the dyno on youtube and am in the middle of a similar build right now and wanted to know more. I am new to STi's, but this isn't my first rodeo, so let me answer some of the questions brought up by people speculating so others don't find this thread and become misinformed.

The numbers you quoted for a stock 04 sti on a dynojet at your altitude, depending on calibration and most importantly in your case altitude correction factor, are pretty accurate. Most in your area would alt correct to ~1.15-1.25.

Stating that it is dangerous to make X hp on X dyno because some guy in timbucktoo cracked a ring land on similar numbers is useless. People have cracked ringlands bone stock! Again, without accounting for the alt correction, the calbiration and types of the dynos (no two are identical), weather conditions, modifications to the car, etc. . . what you really need to be worried about is detonation, not numbers being too high. Knock kills ringlands, not power or torque.

As for the AFRs, he probably has a wideband calibrated for gasoline AKA lambda = 0.85 vs e85 lambda = 1.3 . Assuming that is the case, he is right about in the sweet spot, maybe a tad lean, but nothing special.

Last but not least, the "peakyness" is not because the dyno hasn't been calibrated properly it's because the smoothing is set to 0. The typical standard is SAE smoothing 3-5.

Anyway, great numbers, do you plan on taking it to the track?

Nice numbers! Everybody should take into account that he's way up there too..that car at sea level would make even more power. I had a similar setup to you, save I had EWG and a EL header with stock TGV's. I made 350whp, and 448tq. So I know how much fun your car is to drive! When I first got my bigger turbo I hated it compared to the vf39..but now, thats a different story LOL. Oh BTW, the dynojet I got dyno'd on stock sti's put down 230-235whp. 300 is absurd for a stock sti..

cassiusclay said:

Wow, a lot of misinformation in this thread. I searched a bit to find a thread somewhere about your car because I saw the dyno on youtube and am in the middle of a similar build right now and wanted to know more. I am new to STi's, but this isn't my first rodeo, so let me answer some of the questions brought up by people speculating so others don't find this thread and become misinformed.

The numbers you quoted for a stock 04 sti on a dynojet at your altitude, depending on calibration and most importantly in your case altitude correction factor, are pretty accurate. Most in your area would alt correct to ~1.15-1.25.

Stating that it is dangerous to make X hp on X dyno because some guy in timbucktoo cracked a ring land on similar numbers is useless. People have cracked ringlands bone stock! Again, without accounting for the alt correction, the calbiration and types of the dynos (no two are identical), weather conditions, modifications to the car, etc. . . what you really need to be worried about is detonation, not numbers being too high. Knock kills ringlands, not power or torque.

As for the AFRs, he probably has a wideband calibrated for gasoline AKA lambda = 0.85 vs e85 lambda = 1.3 . Assuming that is the case, he is right about in the sweet spot, maybe a tad lean, but nothing special.

Last but not least, the "peakyness" is not because the dyno hasn't been calibrated properly it's because the smoothing is set to 0. The typical standard is SAE smoothing 3-5.

Anyway, great numbers, do you plan on taking it to the track?

Click to expand...

:lol: I've been meaning to go into further details on people's questions, concerns, and validity of a few things on my tune, but I always forget about this thread when I'm on here.

1. Altitude correction factor is set at a 1.24 on this particular dyno pull.
2. As stated above, the "smoothness" of the graph is due to the smoothing being set to zero.
3. I asked my tuner almost a month ago, whether he adjusts his wideband o2 sensor for tuning (put into the rear of the exhaust), whether he adjusts for lambda (the proper, and easiest way to read ethanol AFR's), or if this is based off of a standard gas based AFR. He stated that he tunes so many cars on E85; Subaru's, Nissan's, Evo's, that he's learned and memorized many of the little details to tuning E85 based cars, which includes knowing the safe spots, where and when you can make proper adjustments in the tune, let alone knowing Gas to Ethanol AFR calculations.

I found out about #3 recently, due to a post in this thread making me sketchy all of a sudden. I wasn't pissed off towards my tuner or anything, just wanted to be taught and know the specifics behind the car.

In regards to the track, I'd like to get out into some autocross and HPDE events this year. In terms of the quarter mile, I'll probably go up to the strip at least once this summer, and get in at least two runs. While drag is fun, I'll be the first to admit I'm uncomfortable launching the car hard at 6k RPM's. I HATED launching at a prepped drag strip, as it was way different than the street. I find it funny how I have no problem taking it up into the higher RPM's in just about any gear, but I'm scared to launch often and break something. Maybe my shitty launches at first had something to due with my now toasted stock clutch. :lol:

ACT XTSS clutch and ACT Streetlite flywheel going in soon!

AirManCam said:

Nice numbers! Everybody should take into account that he's way up there too..that car at sea level would make even more power. I had a similar setup to you, save I had EWG and a EL header with stock TGV's. I made 350whp, and 448tq. So I know how much fun your car is to drive! When I first got my bigger turbo I hated it compared to the vf39..but now, thats a different story LOL. Oh BTW, the dynojet I got dyno'd on stock sti's put down 230-235whp. 300 is absurd for a stock sti..

Click to expand...

Those are the numbers I'm shooting for at this altitude! I did my TGV's myself (not hard to do), and my tuner said he never saw any VF39 STi with basically a stage 2 setup + E85 make numbers like mine has. He related it to the TGV's, and was surprised with the manual boost controller setup's abilities.

I figure with a CAI (currently a short ram), turbo inlet, headers, and an EWG setup I won't have any problem doing it at the same 17.5psi. Faster spool, plus more power throughout the whole powerband would be awesome. I figure at this altitude with this setup, I should be able to crack a 12.75 at the strip. I'm far from a drag racer enthusiast, and prefer the twisties, but in my only two runs in the STi, I ran 13.44 and 13.31 on the Cobb AP Stage 2 map with a 1.88 60 foot being the best run. Baseline Cobb Stage 2 pull on the same dyno the car was protuned on put down 276whp and 296wtq.

Apex Performance said:

Really digging that epic torque number...

Click to expand...

E85 should be the standard pump gas out there

cassiusclay said:

Wow, a lot of misinformation in this thread. I searched a bit to find a thread somewhere about your car because I saw the dyno on youtube and am in the middle of a similar build right now and wanted to know more. I am new to STi's, but this isn't my first rodeo, so let me answer some of the questions brought up by people speculating so others don't find this thread and become misinformed.

The numbers you quoted for a stock 04 sti on a dynojet at your altitude, depending on calibration and most importantly in your case altitude correction factor, are pretty accurate. Most in your area would alt correct to ~1.15-1.25.

Stating that it is dangerous to make X hp on X dyno because some guy in timbucktoo cracked a ring land on similar numbers is useless. People have cracked ringlands bone stock! Again, without accounting for the alt correction, the calbiration and types of the dynos (no two are identical), weather conditions, modifications to the car, etc. . . what you really need to be worried about is detonation, not numbers being too high. Knock kills ringlands, not power or torque.

As for the AFRs, he probably has a wideband calibrated for gasoline AKA lambda = 0.85 vs e85 lambda = 1.3 . Assuming that is the case, he is right about in the sweet spot, maybe a tad lean, but nothing special.

Last but not least, the "peakyness" is not because the dyno hasn't been calibrated properly it's because the smoothing is set to 0. The typical standard is SAE smoothing 3-5.

Anyway, great numbers, do you plan on taking it to the track?

Click to expand...

I'm not certain I understand what you are saying here. The lambda is independent of AFR and is equivalent to 1.00 for the stochiometric AFR of the fuel being used at that moment. To suggest E85 @ lambda of 1.3 on a gauge calibrated for either gasoline or E85 would blow up the engine. If calibrated for gasoline that resulting AFR would be 19.11:1 and on a gauge calibrated for E85 the resulting AFR would be 12.69:1.

Just so we are clear the stoichiometric AFR of gas is 14.7:1 and E85 is 9.76:1

Since the lambda is the same for stoichiometric AFR from fuel to fuel you can simply extrapolate that from a gauge that is calibrated for gasoline and calibrate your tune as if you were looking at gasoline. Essentially when the gauge reads 14.7:1 the real world AFR is 9.76:1. So it is perfectly acceptable to use a wideband calibrated for gasoline to tune a car running E85.

So essentially if your motor makes it's ideal power on gasoline at a lambda of .8, then it is the same for another fuel. Albeit because of (a) the differences in energy output of the E85 charge (b) the cylinder pressures that result and (c) the change in flash point temperatures, E85 does like to be at a richer lambda than gasoline, for the purpose of producing power, which is something like .7 and would make it about 10.29:1 in the power band on a gauge calibrated for gasoline.