Tuning help for E85

[95talonracer]

So if I am tuning for e85 at cruse it would be the same as gas at 14.7 and under full throttle it is also the same as regular gas at 12.0 or a bit less like 11.8 to be safe or is it different for the air fuel ratio for regular premium gas and E85 gas?

[carltalon]

Edit I found a simpler formula.

450/(new injector size * .77)-1

example 450/(880*.77)-1 = -.33....

[95talonracer]

How do I read that on my aem when it only goes down to 10.0?

[carltalon]

the wideband will read what the air fuel ratio would be for gas. you'll want between 12.0 and 12.5 on your guage.

[Halon]

Edit I found a simpler formula.

450/(new injector size * .77)-1

example 450/(880*.77)-1 = -.33....


Where'd you get that formula? I'm on 1600 injectors right now, and my global is at 52 I believe. That formula shows that I should be at 63. That would have me idling at an extrememly rich rate. I think I first started at 60, and at Idle I was seeing something like 18-19:1 ratio. At -52 I'm idling around 14:1 at around 1k RPM.

Also I'll note that my base FP is around 38psi.

[Halon]

How do I read that on my aem when it only goes down to 10.0?

Mine only goes to 10:1 too. I don't really see a need to have one that goes any lower. If your running richer then 10:1, you need to lean that baby out.

[tim]

Where'd you get that formula? I'm on 1600 injectors right now, and my global is at 52 I believe. That formula shows that I should be at 63. That would have me idling at an extrememly rich rate. I think I first started at 60, and at Idle I was seeing something like 18-19:1 ratio. At -52 I'm idling around 14:1 at around 1k RPM.

Also I'll note that my base FP is around 38psi.

What are you using for a fuel pump(s)?

[Halon]

Single Walbro 255hp. Once I max it out, I'll play with lowering the FP, but eventually I'll just run a single Bosch 044 intank.

[95talonracer]

So you run a AF of 12.0 on premium normal gas and if you were to tune to E85?

[Halon]

Yes