SebringLX
07-09-2009, 09:26 AM
Anyone happen to know what the BSFC of E85 on a 2.4L is (SRT internals, 8.1:1 compression ratio)?
I usually use 0.5 as the BSFC for fuel calculations when using normal fuel, but I'm not sure if that's an entirely accurate number to use. I know E85 is supposed to require around 30% MORE fuel than regular gas. Would that make the BSFC of E85 around 0.8 then?
I'm trying to figure out if I don't have enough injector to raise the boost anymore on E85. Problem is I don't have a way to log injector duty cycle right now. I had it holding 22.3psi today with my waste gate duty cycle set to 75%, it's pig rich for a second or 2 while the boost is building, then as soon as it hits full boost it sits in the mid 12:1 range, too lean for my taste. I don't want to waste time trying to fine tune it (remove fuel in the lower pressure range and add fuel in the higher range) if I don't have enough injector to handle it.
Goal was 26psi which I need the higher octane to run safely. E85 is easy for me to get, race gas is not, which is why I was trying E85. I feel the max safe boost on 93 octane pump gas is about 23psi, and I know I have more than enough injector for that. If I can't handle the extra boost on E85, I'll just use 93 and leave it at 23psi until I can afford either larger injectors or meth injection.
I usually use 0.5 as the BSFC for fuel calculations when using normal fuel, but I'm not sure if that's an entirely accurate number to use. I know E85 is supposed to require around 30% MORE fuel than regular gas. Would that make the BSFC of E85 around 0.8 then?
I'm trying to figure out if I don't have enough injector to raise the boost anymore on E85. Problem is I don't have a way to log injector duty cycle right now. I had it holding 22.3psi today with my waste gate duty cycle set to 75%, it's pig rich for a second or 2 while the boost is building, then as soon as it hits full boost it sits in the mid 12:1 range, too lean for my taste. I don't want to waste time trying to fine tune it (remove fuel in the lower pressure range and add fuel in the higher range) if I don't have enough injector to handle it.
Goal was 26psi which I need the higher octane to run safely. E85 is easy for me to get, race gas is not, which is why I was trying E85. I feel the max safe boost on 93 octane pump gas is about 23psi, and I know I have more than enough injector for that. If I can't handle the extra boost on E85, I'll just use 93 and leave it at 23psi until I can afford either larger injectors or meth injection.