Quote:
Originally Posted by Joshinator99
|
I'm not surprised by those results.
Quote:
Originally Posted by JSH
My shop owner has built and tuned many lt4s also never tuned for SOI. Didn't know what it was. My current tuner has never tuned SOI. I sent a log to my previous tuner and he came back and said that SOI of 393 was too high. Both the previous tuner and King had SOI set at 378 to 380. Jason here I believe thinks that 370 is a better number for me. And Josh is saying that 360 works best for him. I need to make some laps and establish a baseline and then try 360-370-380-390 and see
|
King isn't wrong for letting SOI start at 378. I am not wrong for suggesting 368. I suspect you will find no discernable difference between the two on the track.
I actually theorize that spraying at 380-390 when running ethanol could assist with cooling the exhaust valves but I have no way of actually knowing. Some of the earlier Corvette Z06's seem to back SOI up more than you have commanded in the ECU but only sometimes. The Camaro LT4's don't seem to do this. I've always wondered if it was a hidden table or logic in the ECU to perhaps "cool" the exhaust valve by spraying and the end of the exhaust stroke (SOI of 380+)