I've heard from many sources that the 093 pontiac head likes more than 36* of timing. But with a high stall (3000 rpm Art Carr) converter, 8.5:1 compression and 93 oct. gas, shouldn't I be able to run the advance much higher? with a comp cams xe268, what if I started mech. advance at 2400 with all in by 3000 when the converter hits?

BTW, this is with a HEI distributor from a '73 trans-am with MSD module, coil, etc.

If your compression is actually 8.5:1, 93 octane is a waste of money.

this is true...but theoretcially, shouldn't I be able to set my timing higher with higher octane fuel? Right now it's at 41* total all in by 2300, 21* initial. I know that's really high for initial timing, so I'm going to try and shave down the center plate on my HEI distributor, and back some of the initial timing out, since it really isn't necessary.

i think you got the idea that more timing is better,but its not it wont make you faster i would go for total of 38 + or - 2 degrees

yeah man, and with that 268 cam you sure dont need 21* initial. try somthing more like 12 degrees and tune it. I run 18 degrees initial and i have more cam @.050 than you do advertised. What year heads are the 093's? Arent those the original 67' Ram Air 1??? If so you have a load of cash on your hands. Check out these guys for poncho stuff
Kauffman racing, Jim Putler Performance and Rock and Roll engineering. They should be able to help you get that bad boy going. And please KEEP YOUR PONTIAC'S MOTOR A PONTIAC MOTOR. Nothing pisses me off more than a GTO with a BBC. Gosh its blasphemous. Good luck man. Its cool to see somone doing somthing other than a the Big 3

My experience with Pontiac engines is that they are timing sensative, they like timing but are very easy to get preignition and rattle. Pontiac heads have a crappy chamber comparied to the Chevy. I would try to get 36 total with 10 to 12 intial but don't go over 40 for any reason on a Pontiac. My Pops RA III 69 4 sp Goat has 8 intial and 34 total, but it also has 10.50 C.R., I know I wanted to lower it but my Pops said no, it will rattle on 91 oct (Calif we can't get 93).
BTW how did you get the C.R. down to 8.5 with early heads, with factory style pistons and 66 heads you should be at 10.25 range.

well, they're not stock pistons...they're big soup dish types that the previous owner had installed at a local automotive college. The same automotive college also neglected to put in hardened valve seats...so a year after I bought the car, I was running on 6.5 cylinders. ugh!

Anyhow, I started increasing the timing...it started at 41* total, all in by 2200. And certainly not working for me, because I've got "all the right parts" in the engine (except for the pistons, of course) and can't get the thing faster than 14.09 (but that's with a 1.96 60' time)! So anyway, started increasing the timing...all the way up to 52* total with no change...speed up or slow down (via the butt dyno). So I bought a few curve kits for the HEI, played around, and eventually found a combo (stock 493 centerplate, MR. Gasket weights, heaviest springs) that maxed out the motion of the distributor internals. The model I have allows a max of 20* of mech advance without major modifications. Then started cutting the initial down from 36* to 10* in short incremements...it felt faster each time... I'll fine tune once I get to the strip.

as of now, the setup is 10* initial, 30* total all in by 3200rpm