Anyone know the smallest ID of the LS1 throttlebody? I understand it's tapered, correct? Thanks in advance

 

I think it's 78mm

 

75mm

 

Yeah, 75mm. It can be ported to 78 or 81 mm, depending on the port job and the accuracy of your ruler.

 

Right on, thanks guys

I don't think porting would help that much, I need a constant ID, not a taper, so that'd require switching plates and having it professionally bored. It'd probably be easier to just get an aftermarket 84mm unit if it comes to that I think.