Pump Gas and 11:1

[misfit41]

how many are using 11:1 compression and pump gas ? do you find it is a tunable combinatin ?thanks,Tim

[Gasman]

http://www.vpracingfuels.com/vp_01_f...B7C86B4900C50C

Read the specs on VP Performance leaded product.

[tpiini]

Hey Tim,

Not in a Cobra, but my '73 Corvette has a 454 running 10.8:1 with aluminum heads. It runs on premium with no problems at all. In fact, it runs well enough that I'm often tempted to put in some regular just to see what happens.

I think that as long as you're running aluminum heads, 11:1 is doable in any configuration so long as your cam choice matches the C/R.

Tom

[Michael C Henry]

Alluminum heads give at least .5 break.( you didn't say. I'm at 11.5 -1.I have alluminum heads run pump gas but use an additive ment for motorcicyles. It came reccamended with the car from the original engine builder.I had a cam go flat and had the engine torn down ,no damage noticed. I haven't bought any racing gas yet. But plan on splashing some in the tank in the future.

[SCOBRAC]

No. Just say no enless you ave access to 95 octane or better. 98 would be even better. We have 91 in California and life is pretty tough.

[rdorman]

Waiting for the engine builders...............

Setup correctly, I think you can. Premium is 93 octane here with some 94 even available. Aluminum heads, quench chambers, cam, ignition timing, pistons would all have to be right on though. Maybe even coat the piston tops and chambers. Old iron heads, I think that is a big fat forget about it!

Rick

[Bruce Edwards]

Yes you can do it with aluminum heads and the right cam. Would need some fine tuning to keep it from knocking when hot. With a good cooling system you should be able to do it. I have built them up to 12 to one on a 427 with iron heads but they were new Medium riser heads that we polished as well as the piston tops. The trick is not giving the pistons or heads any place to build up a hot spot that will start the knock.