Originally Posted by
kingtal0n
Enrichment needs to be gradual, hold 13.2 to 12.8 for 80KPA to 100KPA ranges dont rush to 12.5 or 12.0
100KPA usually 12.5, low compression can rush 12.0 for torque
105 to 115KPA get down into 12.2's
120 to 150KPA 12.0 to 11.8
150KPA to 200KPA 11.5 to 11.0 on gasoline or stick to 11.8 with E85
By 201KPA It is brushing 11.7 with E85 or 10.9 with gasoline on the in-car wideband, often results with 12.0:1 E85 on the dynometer wideband or 11.2 gasoline
from 205KPA to 315KPA you are holding those a/f ratio while watching(logging) IAT and EGT.
The effects of intercooling and spraying alcohol will vary depending on many factors, for example if the intake is forming ice, the EGT is very low, the a/f should not be overly rich or in the 11's on alcohol at that point, but there are things such as injector end of time tuning which can exacerbate an already over rich condition by spraying late to avoid exhaust valve opening the cylinder may wet down with fuel ruining oil film and polluting fuel and increasing engine wear of the cold cylinders.
Just like with gasoline, if the engine is hot, The EGT Is high, the IAT is getting hot, then its okay to be richer on E85 than 12's because additional cooling is wanted and there is less risk of poor vaporization. However you still must question why is the IAT getting hot, that isn't good. Pressure test the plumbing to ensure no leaks and use the correct size turbo and intercooler and it will not get hot. IAT is a setup issue, not a tuning issue. You can't tune the IAT to be reduced. Compensatory measures for dealing with high IAT are engine safety features, not tuning for power features.
E85 maybe 11.5 to 12.0 air fuel ratio gasoline scale for max output final setting,
E10 closer to 10.8 to 11.0 a/f more common at 20-30psi of boost ranges for any engine 8:1 or 9:1
High 10:1 makes the tuning a bit different. More energy smashing fuel and air together, higher temp, maybe it will need a leaner air fuel ratio for optimal chemical reaction and a colder IAT to control burn rate. OEM turbo engines from the last couple decades in Japan often featured 8.5:1 compression where 95octane gasoline was available standard and all of them are factory intercooler cars emphasis on reducing IAT.
To tune first on gasoline you remove timing to find the EGT ramp of the engine, if possible on dynojet to correlate with lost torque.
From that point a couple of degrees in and thats the lowest pressure you can use with a reasonable EGT making it the ideal timing for daily drivers.
Sometimes the timing can be negative. I think that throws off alot of news. At maybe 2500rpm and 25psi of boost the timing could be -2* btdc. Most people avoid low rpm boost because it 'bends rods' but really it just takes reduced timing to find the minimum pressure and correlate to EGT to make a positive displacement blower work well.
The engine should not break up with minimum timing setting coil D585 which is easily to 1200rwhp or more, 1000lbf-ft at any RPM