Looney Tuning
04-28-2009, 10:42 AM
This Evo X belongs to Jego4u. It is 100% stock right down to the paper filter. Jego4u is the brother of Joneric who owns an Evo 9 RS. I tuned the Evo 9 RS a long time ago.
Here is the data that was logged from the car before I tuned it. As always the 3-D charts are multiple back to back WOT 4th gear runs.
http://www.sr20deracing.com/EVO/Jeff/boost_b4_after.gif
The stock boost peaked at 22.8 psi @ a rather later 4000 rpm. Boost tapered to 14.50 psi by redline. Boost hit the 240 load cell only twice. Not only was the tuned boost higher by 2.7 psi at peak, it also peaked earlier at 3500 rpm. By redline, the car held 18.60 psi of boost, 4.1 psi higher than stock. The car hit the 260 load cell from 3000-3500 rpm and was solidly in the 240 load cell from 3000 to 5500 rpm.
http://www.sr20deracing.com/EVO/Jeff/afr_b4_after.gif
As expected, the AFR on the car was horribly rich. The moment the car reaches 3500 rpm the AFR goes into a tailspin, hitting 10:1 and getting progressively worse are the rpms climb. By 5500 rpm the AFR is at a miserable 9.8:1. After that the AFR leans out into the 10s, hitting 10.4:1 by redline.
The tuned AFR was ~1.75 points leaner from 3500 rpm to 5000 rpm and from 5000 rpm to redline it was ~1.6 points leaner. There was still a slight dip in the AFR at peak spool, but despite that the AFR was leaner than stock by 1.28 AFR points.
http://www.sr20deracing.com/EVO/Jeff/airflow_b4_after.gif
The above chart is a new chart. It shows the airflow in lbs/min. lbs/min is usually used to indicate the maximum efficiency of a turbo. For example, a T3-50 trim turbo is rated at a maximum flow of 30 lbs/min at 2.2 pressure ratio with 58% efficiency. I am hoping that what I am logging here is something similar. But I could be totally off.
I would really love to know the rating of the stock turbo of the Evo X.
Regardless, the stock tune could not muster 35 lbs/min of airflow by redline. The tuned airflow was 3.4 lbs/min higher at 37.9 lbs/min. If that is not an indication of the turbo’s efficiency rating, then it is an indication of more airflow through the engine and possibly more power made.
http://www.sr20deracing.com/EVO/Jeff/boost_gears.gif
I also had the owner row through the gears at WOT. Notice how close the boost per gear at peak is. This was done w/o logging WGDCC. Once I have the ability to log that, the boost through the gears will be dead nuts perfect.
Finally, here are the before and after power charts.
http://www.sr20deracing.com/EVO/Jeff/dyno_b4_after.gif
The car made peak gains of 48 hp and 28 ft-lb of torque. But the area under the curve tells a better tale:
Maximum HP gain: 57 hp from 6500-7000 rpm
Maximum TQ gain: 44 ft-lb from 6000-7000 rpm
The rest of the gains are noted on the graph. From 5500 to 7500 rpm there was an average gain of 50 HP and 40 ft-lb of TQ. This is simply amazing for a stock car.
Here is the data that was logged from the car before I tuned it. As always the 3-D charts are multiple back to back WOT 4th gear runs.
http://www.sr20deracing.com/EVO/Jeff/boost_b4_after.gif
The stock boost peaked at 22.8 psi @ a rather later 4000 rpm. Boost tapered to 14.50 psi by redline. Boost hit the 240 load cell only twice. Not only was the tuned boost higher by 2.7 psi at peak, it also peaked earlier at 3500 rpm. By redline, the car held 18.60 psi of boost, 4.1 psi higher than stock. The car hit the 260 load cell from 3000-3500 rpm and was solidly in the 240 load cell from 3000 to 5500 rpm.
http://www.sr20deracing.com/EVO/Jeff/afr_b4_after.gif
As expected, the AFR on the car was horribly rich. The moment the car reaches 3500 rpm the AFR goes into a tailspin, hitting 10:1 and getting progressively worse are the rpms climb. By 5500 rpm the AFR is at a miserable 9.8:1. After that the AFR leans out into the 10s, hitting 10.4:1 by redline.
The tuned AFR was ~1.75 points leaner from 3500 rpm to 5000 rpm and from 5000 rpm to redline it was ~1.6 points leaner. There was still a slight dip in the AFR at peak spool, but despite that the AFR was leaner than stock by 1.28 AFR points.
http://www.sr20deracing.com/EVO/Jeff/airflow_b4_after.gif
The above chart is a new chart. It shows the airflow in lbs/min. lbs/min is usually used to indicate the maximum efficiency of a turbo. For example, a T3-50 trim turbo is rated at a maximum flow of 30 lbs/min at 2.2 pressure ratio with 58% efficiency. I am hoping that what I am logging here is something similar. But I could be totally off.
I would really love to know the rating of the stock turbo of the Evo X.
Regardless, the stock tune could not muster 35 lbs/min of airflow by redline. The tuned airflow was 3.4 lbs/min higher at 37.9 lbs/min. If that is not an indication of the turbo’s efficiency rating, then it is an indication of more airflow through the engine and possibly more power made.
http://www.sr20deracing.com/EVO/Jeff/boost_gears.gif
I also had the owner row through the gears at WOT. Notice how close the boost per gear at peak is. This was done w/o logging WGDCC. Once I have the ability to log that, the boost through the gears will be dead nuts perfect.
Finally, here are the before and after power charts.
http://www.sr20deracing.com/EVO/Jeff/dyno_b4_after.gif
The car made peak gains of 48 hp and 28 ft-lb of torque. But the area under the curve tells a better tale:
Maximum HP gain: 57 hp from 6500-7000 rpm
Maximum TQ gain: 44 ft-lb from 6000-7000 rpm
The rest of the gains are noted on the graph. From 5500 to 7500 rpm there was an average gain of 50 HP and 40 ft-lb of TQ. This is simply amazing for a stock car.