Re: M&H Flat head

Posted by Jack Vines On 2012/1/28 13:18:50

There's a reason there are no high compression flathead engines. Others here have far more experience than I have with flatheads. However, in my limited experience, because of the wide, inefficient combustion chamber design, on the same fuel, Packard flatheads ping at much lower compression ratios than do OHV8s. I always recommend running at least one grade higher octane on a flathead I8 than would be required for the same compression ratio on an OHV8.

jack vines