SI valves

[blackbombshell95]

he ruined my CC. lol. fixable. i want a pic of the reshaped exhaust port . my sweet heads.

[SappySE107]

Wow, really? They look like stock replacements to me.

GM screwed up with the casting and machining of the heads. Machine shop told me its very common, and ive seen it on DOHC heads as well. At least its not too expensive/hard to fix it though.

[Fedaykin]

SI sent me the 2.8 8mm valves instead of the 11/32" valves.... new ones will be sent...

[SappySE107]

I checked out these valves, and yeah, they aren't stock replacements but the work they do compared to stock replacement isn't really "port flow". I can measure, but the stem just barely gets smaller. Stock replacements look like ass, and aren't cleaned up on the lower stem like these are.

[blackbombshell95]