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Discussion Starter · #1 ·
Below are two corrected graphs. One has my max HP(381whp), the second had my max Torque(402.8 ft-lbs). The max torque graph was a relatively early run, taken while the engine and intercooler were still cool. When compared to the final graph (high HP graph) it also shows some of the progress in power gains I was able to achieve during the dyno tuning session. Unfortunately, I ran out of time to finish fine tuning the fuel and ignition maps, but I should have enough info on my datalogger to make decent adjustments for my next visit to the dyno. Also, I was only running 20 psi on this tuning session; my next visit will probably be at 24 psi.
 

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Discussion Starter · #2 ·
Here's the graph with the high torque numbers:
 

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Discussion Starter · #3 ·
Below is the UNCORRECTED graph:

Just a reminder for everyone who doesn’t remember my car, it’s a 1998 2.5 RS. I recently changed the block to a 2.5 STi block.

Also, many thanks to Joe at Mike Shaw Subaru / Flat 4 Engineering for helping me source all the parts I needed for the fabrication of this project.
 

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Discussion Starter · #5 ·
Heads are phase 1 1998 2.5 DOHC heads. Also, this was taken with just 91 octane super unleaded.
 

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Looks nice, what turbo are you running? I would also like some tuning help, what ecu are you using.
MCL
 

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Did they tell you how/why the 1.19 correction was necessary? 62whp seems like a big correction for most likely weather conditions, also dynojets are notorious for reading higher. Not hating, just wondering.

-mike
:)
 

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MJU1983 said:
Did they tell you how/why the 1.19 correction was necessary? 62whp seems like a big correction for most likely weather conditions, also dynojets are notorious for reading higher. Not hating, just wondering.

-mike
:)
Their dyno erroneously applies a normally aspirated SAE correction factor. In warm weather, it's worse - closer to 1.25 !

Anyways, congrats Mark. The uncorrected output would give you the highest dyno-verified [Subaru] output numbers in the state, no?

-Pace
 

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Very nice numbers

Marc:

Very nice numbers!!

Just thought I twirl some numbers, using the computations I usually use, that would equate roughly to a drag strip run of :

about 12.05 @112 mph with no nitrous, which would make you the fastest subaru up here at altitude.

:cool: ;)

Thats assuming a race weight of 3300# which I think is a bit high for your car.

Larry
 

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Discussion Starter · #11 · (Edited)
Wicked - Turbo is a custom TEC turbo based off a Garret ballsitic GT35R. Also, I'm willing to help anyone with tuning as long as I have time!!!

Pace - Yeah, the correction factor is a mysterious thing with those guys. I can't get a straight answer from anyone about it, but I sure like having the bigger number on a piece of paper!!! The correction factor compensates for temperature, altitude, and humidity to try to give you a sea level equivelent at 'standard' atmosphere conditions.

As far as HP titles, I think it is the Colorado record. In fact, I think i had the record with the old 2.2 L engine dyno run?

I'd like to get a good conversion factor for drivetrain loss, so anyone with helpful answers please chime in!!!
 

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Discussion Starter · #12 ·
hotrod - the car weighs in at 2800 without the driver and a full tank. I've gotten all my drivetrain bugs worked out from last summer, so maybe i can finally go for some serious 1/4 mile runs this year. 12.05 seems really optimistic, but it would sure be nice!!!
 

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Flywheel hp

Here's the formula I use, it figures based on flywheel hp, and I usually assume a 1.2:1 ratio from flywheel to wheel hp.

a Strong Stock WRX dynos at around - 176 hp or so (depending on dyno type) with a rated stock output of 227.

But I suspect the dyno numbers are a bit low due to several factors, like friction losses due to tiedown forces, slippage on the roller, and cooling on the intercooler and air intake is not representative of real world conditions which is why I go with the generic 1.2 value.

(mph/228.4 ) ^3 * (weight in lbs) = mph trap speed

Ideal trap to ET relationship for our cars is approx

1350= mph*ET

If you plug in stock WRX values of 3300 for weight and about 94 mph trap speed you will get a flywheel hp number of about 227 which is the stock rated hp.

Larry
 

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Discussion Starter · #15 ·
pace said:
At 2,800 lbs race weight, high 11s would be well within reach. That would be a run I'd wanna see!

You just gotta stop breaking crap during launching.. :D

-Pace
Easier said than done!!! Maybe if I convert to 2WD!!!
 

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Re: Flywheel hp

hotrod said:
Here's the formula I use, it figures based on flywheel hp, and I usually assume a 1.2:1 ratio from flywheel to wheel hp.

a Strong Stock WRX dynos at around - 176 hp or so (depending on dyno type) with a rated stock output of 227.

But I suspect the dyno numbers are a bit low due to several factors, like friction losses due to tiedown forces, slippage on the roller, and cooling on the intercooler and air intake is not representative of real world conditions which is why I go with the generic 1.2 value.

(mph/228.4 ) ^3 * (weight in lbs) = mph trap speed

Ideal trap to ET relationship for our cars is approx

1350= mph*ET

If you plug in stock WRX values of 3300 for weight and about 94 mph trap speed you will get a flywheel hp number of about 227 which is the stock rated hp.

Larry
On our Dyno Dynamics dyno, a stock WRX makes 155-160 whp.

-Mike
 

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Very impressive. I am mostly impressed by the spool up on the GT35R from the looks of it right around 4000rpm. What gear did you do your dyno pull in?
 
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