So went and measured my stock ls intake manifold to clear up what size i should buy..... and now im conffused! The inlet on the mani. was between 2.5"-2.75"(outside to outside). so i measured the coupling that is for my intake and it is damn close to 3". So now I dont know what to think.

those of you that have these for your stock ls intake manifols, what size did you guys buy. thanks.

 

Use the measurement on your manifold.

EDIT: I dont own an LS.

 

I used a 2.5 coupler and just stretched it over t/b.

 

Better to have one a little small than too big. You can heat them and stretch them but they dont shrink well