machining · FF-0156

How far should a Ford Flathead be bored, and which pistons should it use?

Steve gives standard bores of 3 and 1/16 on early engines and 3 and 3/16 on the later 239 and 255 engines, and says most blocks have already been bored several times. He prefers to keep the bore to the minimum: 3 and 5/16 is common now, but he would have .100 over pistons made before boring further. Cast pistons are fine for a standard rebuild; he likes forged pistons in a supercharged engine.

Expert

Steve Coppock

Evidence

expert attributed

Component

cylinder bore and pistons

Applicable scope

Performance Ford Flathead V8 build as described by Steve Coppock