airflow · FF-0233

How much does relieving a Flathead block improve airflow?

Joe says cutting out material between the valves and the cylinder does work for horsepower. A good relief, about an eighth of an inch deep and following the gasket line, is good for about 15 percent more flow, which he equates to 15 percent more horsepower.

Expert

Joe Abbin

Evidence

expert attributed

Component

block relief

Applicable scope

Supercharged Ford Flathead V8 with the Abbin-designed blower kit now built by Coppock Performance and Engineering