Originally Posted by joelster
The tune, the plug heat range, the cylinder head material, the amount of timing, the density altitude (he's way up) all have a bearing on whether it will live on pump gas. I'd bet money he'll be fine. My car is at 11.77-1 static and it purrs on pump 93.
He's got a pretty tight budget, but anything will be better than those iron dinosaurs he's running now.
Totally agree. Makes no sense to go with a 4.56 gear and THEN buy a taller tire to knock it down a bit, like guys are recommending in the other thread. In fact I would leave it alone and see if it makes it to the 7's just the way it is.
A cam like that would be really good here. I'd wake it up a little with some 1.6 rockers and the appropriate springs. It should pull a little higher than 6k though. Maybe you didn't have enough cylinder head to feed the motor?
i used 1.6 rockers on the intake and 1.5 rockers on the exhaust side to help even out the dual pattern cam, my heads were DART 200cc platinum's with decent cleaning up done. the motor pulled past 6000rpm but my peak hp (512) was made right at 5900rpm.
i never said that it was impossible to run 10.8:1 on pump gas, but as you mentioned, a lot goes into making it run on pump gas. my previous set up was 10.4:1 and could run on 93 pump gas. my current set up has 11.2:1 and does not like pump gas.