fastfox86

Timing retarded as far as yours was is definitely going to rob some serious power. I'm surprised you could light em up in first gear. I' would say though, incrementally from where you are at now up to about 16, the difference will still be noticeable, but not as drastic as the jump from 6 to 12. put some 93 in it and bump it up to 14 or 15 and see how it feels. You know you might also notice lower underhood temps with the advance.

5.0_PR

The "Iced Intake" is referring to putting a bag of ice on the intake manifold between runs. The colder air is more dense, and provides more power.

Twisted

Thanks PR and Fastfox. I just may go for 14, Fastfox--probably wait till I'm bored with the car's power again. So the day after tomorrow, I'll bump it up.

JD1969

At some point power is going to fall off, the idea is to find that sweet spot, this is where a dyno is handy.

silver91gt

I could run 17 degrees initial timing with my stock heads

when I went on the dyno, I had it set at 12 degrees and made a baseline run,
then I advanced it to 16 and I gained 20hp and 19ft/lbs.

I run 92 octane fuel always, and there was no detonation.

I heard aluminum heads like even more timing, so I run 17 degrees now.
the plugs are a tiny bit whitened, but it sure runs strong.

Twisted

Wow! From 12-16 degrees you made 20 horse? You're tempting me, Silver91. Hell, I'm still trying to get traction in first gear! At any rate, thanks for the reply.