Looney Tuning
04-12-2009, 06:33 PM
This Evo X belongs to Mizuvo. Its only power mod was a Works drop-in filter. Aside from that it is 100% stock. The last two Xs that I tuned had an AEM intake and a TBE. I wanted to tune an almost stock X and see how the tune differs. The car also did not have the factory re-flash done to it, so it was even a better candidate for a tune.
All runs were done in 4th gear and each chart contains 4 back-back runs. The numbers w/o brackets are averages and the numbers in brackets are peak numbers.
Because it was running the original flash, it ran extremely rich. I felt sorry for the poor oxygen sensor. Here is the before and after AFR on the car.
http://www.sr20deracing.com/EVO/Calvin/afr_before_after.gif
The stock AFR dips into the 9s the moment the car goes into WOT. It stays in the 9s all the way to 6000 rpm and then climbs back into the low 10s by redline. What a stupid-stupid tune. I had to massively lean out the car to get it back into the mid 11s. From 3500-4000 rpm I leaned out the car by 2 full AFR points; from 4500-5000 rpm by 1.8 AFR points; from 5500-6000 rpm by 1.55 AFR points; and from 6000 to redline by ~1.3 AFR points.
The boost was also adjusted. The stock boost peaked at 4000 rpm registering an average of 21.28 psi (21.90 psi max) and tapering to an average of 13 psi by redline (13.90 psi peak).
http://www.sr20deracing.com/EVO/Calvin/boost_before_after.gif
The tuned boost was not only higher by an average 2.6 psi at peak, it was also reached at 3500 rpm. By redline average boost was 4 psi higher than stock. Peak boost hit 18.30 psi in one of the runs whereas stock the car could not break the 14 psi barrier.
The best way to show the differences is in the following graph:
http://www.sr20deracing.com/EVO/Calvin/boost-afr_chart.gif
Notice how much leaner the car is than before. I suspect that the AFR meter flat lined because the car was so rich. It is entirely possible that the car ran richer than 9.60:1 when we logged it, but the meter could not go that low. Also note how boost peaks earlier than stock and holds better to redline than stock. The gain in boost in the mid-range is especially fat and meaty.
Below is the power increase that the car experienced from the tune. I averaged the last two stock runs and the last two tuned runs.
http://www.sr20deracing.com/EVO/Calvin/dyno_before_after.gif
The car made gains everywhere in the power curve. The biggest gains, though, were above 5000 rpm. The biggest average power gains were:
51 hp between 6000-6500 rpm
43 ft-lb between 5500-6500 rpm
The other power gains are noted on the chart.
The Evo X is begining to impress me. It makes for a great daily driver, something that I do not have in my Evo 9. There might just be a burnt orange Evo X in my driveway at the end of 2010.
All runs were done in 4th gear and each chart contains 4 back-back runs. The numbers w/o brackets are averages and the numbers in brackets are peak numbers.
Because it was running the original flash, it ran extremely rich. I felt sorry for the poor oxygen sensor. Here is the before and after AFR on the car.
http://www.sr20deracing.com/EVO/Calvin/afr_before_after.gif
The stock AFR dips into the 9s the moment the car goes into WOT. It stays in the 9s all the way to 6000 rpm and then climbs back into the low 10s by redline. What a stupid-stupid tune. I had to massively lean out the car to get it back into the mid 11s. From 3500-4000 rpm I leaned out the car by 2 full AFR points; from 4500-5000 rpm by 1.8 AFR points; from 5500-6000 rpm by 1.55 AFR points; and from 6000 to redline by ~1.3 AFR points.
The boost was also adjusted. The stock boost peaked at 4000 rpm registering an average of 21.28 psi (21.90 psi max) and tapering to an average of 13 psi by redline (13.90 psi peak).
http://www.sr20deracing.com/EVO/Calvin/boost_before_after.gif
The tuned boost was not only higher by an average 2.6 psi at peak, it was also reached at 3500 rpm. By redline average boost was 4 psi higher than stock. Peak boost hit 18.30 psi in one of the runs whereas stock the car could not break the 14 psi barrier.
The best way to show the differences is in the following graph:
http://www.sr20deracing.com/EVO/Calvin/boost-afr_chart.gif
Notice how much leaner the car is than before. I suspect that the AFR meter flat lined because the car was so rich. It is entirely possible that the car ran richer than 9.60:1 when we logged it, but the meter could not go that low. Also note how boost peaks earlier than stock and holds better to redline than stock. The gain in boost in the mid-range is especially fat and meaty.
Below is the power increase that the car experienced from the tune. I averaged the last two stock runs and the last two tuned runs.
http://www.sr20deracing.com/EVO/Calvin/dyno_before_after.gif
The car made gains everywhere in the power curve. The biggest gains, though, were above 5000 rpm. The biggest average power gains were:
51 hp between 6000-6500 rpm
43 ft-lb between 5500-6500 rpm
The other power gains are noted on the chart.
The Evo X is begining to impress me. It makes for a great daily driver, something that I do not have in my Evo 9. There might just be a burnt orange Evo X in my driveway at the end of 2010.