What I learned at Pettis Performance years ago was that going from say 9.5 to 11.5 comp. made way more power than going from 12.1 to 14.1 fwiw. On another note however, I have a customer w/a 3450 lb Chevelle on 93 pump gas w/a 572 at 11.7 comp. that went a best of 8.84 at 151 w/a 2-circuit cast 1250 Dommy..........

Yes, it does work that way. The compression scale is shaped like a pyramid.

He may get away with 11.5 on pump gas and run a whole lot better.

I think that's extremely lucky with 10:1 from what I have seen. Maybe you just have real good cylinder heads with high velocity ports? My old 408 went 10.38@131 on 11.25:1 at 3300# with a 268@50 roller.

I just ran my 10.5:1 512 out at milan Wednesday. Car didn’t hook with the 6 year old drag radials. I gotta think it’s 3450 with me in it. All steel 69 dart except for the hood and front bumper. First time out with this combo, I have some work to do. I did make some other better passes earlier in the evening but the timing system was down. I think it’s more about combo than anything.

Looks like there’s a “9” in it with some tires.

That’s Andy’s old cam, right?

it is, runs super hard!! Is that one of your grinds?

If it’s the 264/268-108....... then yes, it is.

I thought I might be, damn good running cam.

I was very please with a Comp Cams solid roller similar to this one, it ran really good in my old pump Gas Duster good, 9.993 at 134.7 MPH through a complete to the rear bumper 3 inch exhaust system and air cleaner on at 3450 Lb. with me in it cork up

Nice results definitely started making steam in 2nd half of the track

Nice and congrats. Runs great on pump gas. What's the duration at .200 and what's the lobe lift on that cam? Thanks

Thanks! I also had a mismatched wood carb spacer on it just to keep heat off the carb. Need to find one that fits the cloverleaf.

Thanks

Very nice improvement and congrats on the new bests! Did you change pistons for the compression increase?

No, i shaved the heads .45" i think. I will take off more next time they come off. It loves compression. No more pump gas motors for me, unless its E85.

No more pump gas motors for me, unless its E85.




You will love it

e85 is awesome. I've been running it for years on my small block street/race car. 13:1 compression Eddy head motor, runs 10.19 at 130. If I recall corretly, my car picked up a little over a tenth when I made the switch to e85 on my old 10.8:1 compression small block.