,
Naji also did some slight tweaks to the fuel and ignition tables to lean the engine out slightly to maintain an air fuel ratio in the high 11’s. Timing in the high load and rpm areas of the map was reduced to around 17 degrees, about 5 degrees less than stock to get rid of our knock. The Evo X 4B11 cylinder head can tolerate a lot more timing than the 4G63 could. We are only running about 7 degrees in the same area of the map with our Evo IX.
Naji also modified the MIVEC maps that control cam timing for the intake and exhaust cam adding more overlap and smoothing an odd dip in in the intake cam map in the middle rpms. We think that was done for emissions reasons as we don’t think it helps engine power production or driveability at all! Changing the cam timing made the boost come in around another 200 rpm sooner and greatly improved throttle response.
 |
The results with the AMS Widemouth downpipe and test pipe in place with no tuning. Although we registered great gains with just this, we did have to retard the timing above 6000 rpm by another two degrees to avoid knock. With no tuning at all, a Evo X with an intake, exhaust and downpipe will detonate pretty badly. Overall we had to pull about 5 degrees of timing at this point to avoid detonation with no other tuning. Note that the AMS parts leaned out the air fuel ratio, although it is nowhere near dangerously lean.
|
 |
| Naji changed the cam control tables for more advance on the intake cam and slightly more retard on the exhaust cam increasing and overlap. He raised the boost slightly and leaned out the air fuel ratio slightly as well. After Naji's tune, the car had a lower knock count than stock! |
Our mild tune really made our Evo come alive, it pumped out 29 more hp and 22 lb feet of torque for a total of 13 hp more than with just the downpipe alone. So far our Evo X is really responding to simple bolt ons pumping out 80 more hp than stock at 341 whp! Even at our low state of modification the AMS Widemouth Downpipe really works our car's power output and is helping prepare it for more power mods in the near future.
 |
| A quick comparison of where are car is now vs stock. At 341 whp it is making 80 more hp than stock, not bad for just a few easy bolt ons and a conservative tune. |
Currently it looks like our turbo is going to be the bottleneck in our quest for more power and we have a big Greddy intercooler, Cosworth cams, Aeromotive fuel pump, RC Engineering injectors, Full Race Pro Stock exhaust manifold and a Garrett GT Turbo upgrade coming soon. We will be reporting on all of this in upcoming segments of Project Evo X GSR!
