Hey guys, can anyone tell me how I can tell the difference from a cast piston and forged piston just by looking at them? I've got the part number from the inside of the skirt, but I'm not sure what it means.

thanks.

 

go to summitracing.com and type in the part number in their search thing, that should tell you what ya want.

But couldnt tell you the difference, sorry

 

the tolerences are tighter. thats what i was told atleast... forged pistons are a forged aluminum with a tighter tolerence, while cast, is just a molded aluminum mold.

 

1.)Give them a tap with a wrench
2.) listen, it they ring they're forged, if they just give a thunk, they're cast.
3.)Repeat steps 1 and 2 until they loose their entertaining effect
4.)post results.

 

forged pistons aren't machined to any tighter spec than any other piston. forged pistons are a bit less diameter or out of round than cast. that's why forged pistons will make a little bit of noise untill they warm up and expand a little.

 

Forged pistons are stronger than cast pistons, and can handle detonation alot better than cast or hypers. Thats why they are the prefered pistons for very high power engines, as well as forced induction (blown, N2O, turbo) engines.

 

if by stronger you mean tensil strength hypers are stronger however they are also more brittle.

 

Yup. Forged can handle more abuse, but hypers are harder.

 

I like that. hahaha