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View Full Version : Begining of month tune: +45 hp & +55 ft-lb



Looney Tuning
08-03-2009, 11:19 AM
This Evo X GSR belongs to forum member TRUSTcompany9000. It is one of the earliest Evo Xs to be purchased in the US. He bought it the moment they became available on the market. It now has 30,000 mile on the odometer. The car had the following modifications done to it:

AMS UICP
AGP CAI (first time I tested an Evo X with this intake)
Perrin MBC
SpeedCircuit Test Pipe
AMS single exit catback

The first thing to do was to download the rom and set it up for mode 23 logging. The car had the earliest 015 rom, it has not been re-flashed by the dealer with subsequent rom updates.

The second imperative was to check the fuel trims. As I have noted in my sticky, stable fuel trims are essential for a consistent AFR on the Evo X. We take out the car for a steady speed drive. After 35 minutes, the fuel trims top at 9.75%. Basically, the ECU was sensing a lean condition from stoich and adding fuel to bring back the AFR at cruise to 14.7:1. While this trim was not maxxed out, there are reports of Evo Xs with this intake triggering a P0171, system too lean, code. Therefore, that high trim had to be fixed. I adjust the latency on the injectors and we go for another half hour drive. The trims drop down from 9.75% to 5.85%. More importantly, the trims stay at +/- 5-6% throughout the tuning session.

We also baselined the car, but since it had an MBC it was very hard to match the stock boost. An MBC tends to hold more boost by redline than the stock set-up even if we were able to match the stock peak boost. Here are the before and after 3D WOT chart of the data before and after the tune:

http://www.sr20deracing.com/looneytuning/Evo/Ben/psi_b4_after.gif

As mentioned the car had an MBC, so the baseline peak boost did not quite match the stock boost. Still, the boost was higher than baseline by 4.69 psi at peak. At redline, the baseline boost held much better than stock boost would. Usually, the stock boost is ~15 psi by redline. This car’s baseline boost was ~2psi higher. Despite that, the tuned boost was higher than baseline by 2.57 psi at redline. Also worthy of note is the 500 rpm earlier peak spool-up on the tuned boost vs. the baseline boost. The car was hitting peak boost at a stunning 3000 rpm.

The baseline AFR was also different than what you would expect from a stock Evo X. The MBC changed the load cells that were hit and therefore, the AFR fuel targets. The baseline AFR was actually semi-decent on this Evo X with a lean condition from 3500 to 5000 rpm and then a not-so-decent rich condition from 5500 rpm to redline. The tuned AFR was lean at spool-up (12:1), and then held in the mid 11:1 from 3500 to 6000 rpm, and finally tapered slightly below 11:1 by redline.

http://www.sr20deracing.com/looneytuning/Evo/Ben/afr_b4_after.gif

The baseline timing on this Evo was causing the car some knock. I logged 5-7 counts on the baseline runs across the rpm. The MBC was holding the boost better, but the car had too much timing and was knocking as a result. I had to retard timing significantly to cure the knock on this car: 5* less timing at peak boost; 4-5* less timing in the mid range; 5-7* less timing at the top end of the rpm range. That is what the car liked. This timing kept the knock at a random 1-2 counts; anything higher triggered higher knock levels.

http://www.sr20deracing.com/looneytuning/Evo/Ben/tim_b4_after.gif

So how much power did this car make? The car made the following max and peak gains:

Max power gain +45 hp
Max torque gain +55 ft-lb (most impressive gain)

Peak power gain +42 hp
Peak torque gain +33 ft-lb

The gains would have been higher had we started from stock boost. Alas, the car already had an MBC on it and it is very difficult to get the boost to taper like stock with an MBC.

http://www.sr20deracing.com/looneytuning/Evo/Ben/dyno_b4_after.gif

The most impressive thing about the tuned power curve is the very early onset of torque. Baseline peak torque hit at ~4400 rpm whereas tuned torque hit almost 1000 rpm earlier. That is simply amazing. Must be a fun car to drive daily. :twisted:

Azian
08-03-2009, 11:26 AM
30,000miles holy crap O_O

gengo
08-03-2009, 11:32 AM
Getting an extra 55 Ft-lbs at 3400RPM is NICE!

alan678
08-03-2009, 12:01 PM
Good stuff NJ!



30,000miles holy crap O_O


Someone that drives more than you ben...lol....time to go for a drive!

TRUSTcompany9000
08-03-2009, 12:09 PM
Apparently Ben's drive Evo's quite a bit lol, as that's my name as well :)

The car certainly is a torquey little thing, and I love it. It doesn't get any more fun than that.

I want to give some definite good feed back about Naji, I can't express how much he taught me throughout the entire tune. Every single little thing that was changed throughout the tune was explained in depth to me as to why, so that I knew not only what was happening but why it was happening as well. He took his time, was very meticulous, and a good time to hang out with in the down time between pulls. Thanks Naji, I really appreciate it! You've done a hell of a job, keep it up!

rojoX
08-03-2009, 01:27 PM
nice!!! good stuff!

big boss
08-03-2009, 02:10 PM
O0 Naji Thats some crazy TORQUE #'s!!!! DUDE "U" Are the Man!!! 8) NAJI Again Thnx for taking your time with mine.....Now I cant wait To add MORE POWER! lol :twisted:

TRUSTcompany9000
08-03-2009, 07:23 PM
Now I cant wait To add MORE POWER! lolÂ* Â*:twisted:

+1