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View Full Version : Evo X Tune: +55 hp & +52 ft-lb



Looney Tuning
10-11-2009, 10:43 PM
This Evo X GSR belongs to forum member thisboyskill. This is the 5th Evo I have tuned since the last time I posted. Sometimes I get into one of these moods where I want to get away from reading and posting about tuning.

The owner contacted me back in mid-July for a tune, but he never had the time to follow through with it. He finally had time to come for a tune on his Evo X this Sunday. The car had the following mods:

Greddy Downpipe
Tsudo testpipe and Full exhaust
AEM Intake

The car had more than 13K mile on the odometer and that means that it could be a candidate for the infamous defective fuel pump relay. Luckily, it did not have a defective relay YET. It could develop later on and that is why I recommend changing this relay every 15K miles. Mistu is now selling a different number relay (green color), but the jury is out if this is going to solve this problem for good.

Recently I have started doing 3rd gear and 4th gear baselines since on DLL 3rd gear produces higher hp numbers than 4th gear. So the baseline consisted of 2 4th gear WOT runs and one 3rd gear WOT run.

Following the runs, I set out to fix the cruise fuel trims. The trims on this car were maxed out @ +12.5%, triggering a p0171 (system too lean) on occasion. I would log the AFR on a stock Evo X with an AEM intake when the trims are at 0% and then log the AFR when the trims are at +12.5% and see the power difference that makes. But that is for another time.

A 0.15 ms adjustment of the injector latency table brought the cruise trims down to a stable +7%. Now it was time to tune the car. Here are the before and after charts, starting with the boost:

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

The peak stock boost on this car was on the high side, but it peaked late at 4000 rpm. The tuned peak boost was only higher by ¾ of a psi, but it peaked 1000 rpm earlier!!! The stock redline boost tapered to 14.42 psi by redline, while the tuned boost was almost 4 psi higher at 18.35 psi.

The AFR was abysmal even with the AEM intake since the +12.5% fuel trims wiped out the lean effect of the AEM when the trims were at 0%. The AFR fell into the 9.xx:1 post peak spool and stayed there across most of the rpm range. The car was stuttering up top due to the richness of the AFR. The tuned AFR spooled in the 12.xx:1 ration and stayed in the mid 11:1 ratio; tapering to 11:1 by redline. Post redline, the AFR tapered into the 10.8-10.5:1.

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

The timing was retarded from the ridiculously advanced state of the stock tune. The tuned timing was 3* lower than the stock @ 3500 rpm; the same as stock at 4000 rpm; 5-6* lower than stock between 5000 and 6000 rpm; and 9-10* lower than stock from 6500 rpm to redline. Anything higher than that triggered more than 1-2 counts of knock.

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

The car responded very nicely to its tune. The power charts below tell the story. First is the before and after 4th gear DLL power charts:

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

The entire area under the curve improved. The gains were as follows:

Max power gain: +55 hp
Max torque gain: +52 ft-lb

Peak gains are slightly less, as they almost always are:

Peak power gain: +46 hp
Peak torque gain: +43 ft-lb

The 2nd chart is the 3rd gear before and after runs. It has been my experience that 3rd gear Evo X runs in DLL produce 10-15 hp higher peak gains than 4th gear runs. This Evo X behaved the same as all the others did.

http://www.sr20deracing.com/looneytuning/Evo/Jorge/dyno_b4_after2.gif

Again, the entire area under the curve improved. The gains were as follows:

Max power gain: +48 hp
Max torque gain: +45 ft-lb

Peak gains are slightly less:

Peak power gain: +39 hp
Peak torque gain: +36 ft-lb

The owner of the car is going to swap to an Injen intake with LICP/UICP, add an IC, paint the car flat black and come back for a re-tune :D

big boss
10-12-2009, 03:24 AM
NICE NajiÂ* O0 cant wait to see the numbers wit the Ijen setup ;)
Congrats thisboyskill bet ur liken it more now! O0