I am getting a couple of silicone hump hoses soon. They are those silicone couplers with one ridge in them (similar to an LS1 smooth bellow hose). My question is, what overall diameter am I going to need to get a snuge fit over the stock throttle body? How about the airlid (dual airbox iroc intake)?

I am doing this so I can replace the accordion style TB bellows with a nice smooth flow friendly section of 3.5" PVC piping.

 

For the throttle body, use a coupler with a 4" ID.

For the airbox, I'm not sure but I think it's a 3" ID....which is probably closer to a 3.5" OD. It would be best to measure this one yourself.

 

Thank you!

I plan to measure it myself. You helped alot tho - because I didn't want to mess up with my choice for ID vs OD. It's a simple mistake, but it would cost me days in the stupid fabrication as I have to order these things (they're hard to find) from a turbo company.

Appreciate it. Just to clarify... an ID is smaller than an OD.
eg: a 3" ID works out the about 3.5" OD, and a 4" ID works out to about 4.5" OD. Right?

 

Yup, that's correct!