Guys running pump gas, and alum heads

[Turbo__Tim]

My main question is this: What timing are you running. I tried to stay with 21* but cranking the timing to 25* really allows me to chew up the gas.

I'm staying with 94 sunoco.....

I don't think the cylinder temps are hot enough even yet. Adding a tiny bit of alchy seems to bog the engine somewhat. Right now the egt's are at 1325* at 75 MPH, and the 0-2's are at .830 at the same Mph.

I would like to hear from you guys that are running alum. heads to get an idea as to what timing you are running.

Especially those of you that are running pump gas and alchy.

I'm at 25* timing now, 19 psi. No knock without alchy.

I'd like to keep the boost at 19*. I'd like to add a little alchy, but it boggs the engine a bit. I'm undecided whether to add timing, or reduce the fuel input to aid the alchy injection.

I'm thinking of going to 27-29* timing. With alchy, of course......

Am I nuts? Is anyone running this high of timing with pump gas, and alchy?

 

[matt87]

man, why play with fire like that?! i've always heard that low timing and more boost is better than vice versa. high timimg with pump gas is a receipt for disaster.

 

[Turbo__Tim]

Yeah I know, that's why I'm asking. What timing were you running?

 

[matt87]

w/o race gas of 110 or better i use 18 degrees with 94 octane and around 20-22 psi boost. with 110-116 octane i run 26 degrees timing and whatever boost i can get it up too, usualy 25 psi. keep the timing low and nudge the boost up, with alky i see alot of guys in the 20-22 degrees timing range and some use 18 degrees, all depends on what your setup likes.