COBB AP/ATR Beta Fuel Scaling

[rfinkle2]

cld12pk2go is quiet about it, but has some big balls!

Sick VD.

[Dano]

so does Anthony.....to soon???

lol

[RichieRichness]

Not much talk of fuel scaling lately so i'll wake things up. I finally was able to test the fuel scalar. Here are my results from a 93 octane tune to a 3.5 gal mix of e85. I used the following settings.

Injetor Scalar = 1.1
Specific Fuel Gravity = 0.75

AFR Target = 12.1

Timing from 3k to 6k rpm:

3.00	4.00	5.00	5.50	7.00	8.50	10.00

93 octane vs e33.jpg

[Enki]

You have quite a bit more room up top. I was running 14 @ 6k on 3 gal mix. Otherwise, looks like you only need a slight bump to correct the MAF. What do the trims look like?

[RichieRichness]

Originally Posted by Enki You have quite a bit more room up top. I was running 14 @ 6k on 3 gal mix. Otherwise, looks like you only need a slight bump to correct the MAF. What do the trims look like?

Oh yeah I know. I was running 14* @ 6000 rpm on my older map but wanted to put a side by side comparison together with the only change being the scalar.

Fuel trims are not terrible (between 0 and -5) but was not expecting them to be so far off considering my WOT values are so close.

[Enki]

Might need a bit of a tweak on the FSG value then; you're only off about 1.7% up top (assuming 12.2 peak afr @ WOT), so pulling up to 5% fuel could mean that you're flowing too much fuel due to the weight not being correct.

Assuming 3.5 gal mix, with e75 at the pump; this comes out to roughly ~e24 in your tank (might be lower, in which case you'd run richer with the following settings):

FSG: 0.7484
Scalar: 1.0747

Worst case is you run a 12.3-12.5 AFR if your MAF cal is actually off a bit; with so little timing in the engine though, don't think that will be a problem for testing.