Boring the H.O. throttle body to 60 mm

anybody got a good write up on doing this?:wave:

Why? I see no gain in performance by doing so. My .02.

I had mine bored to 62mm(same size as the hole in the manifold) and I love it. Increased throttle response, more control, etc. If you already have an aftermarket exhaust, the bigger tb complements it very well.

I have bored one to 64.4mm and another to 64mm. You need to do it on a mill with a boring head if you want good results. The bore has to be perfectly perpendicular to the table. The throttle blade shaft will have to be filed out to take a bigger throttle plate. The throttle plate is best done on a lathe. If you have any more specific questions, PM me. I really didn't notice any improvement except better throttle response. I am dealing with restrictive exhaust and probably a plugged cat. The difference will be noticed in engines with a free flowing exhaust and intake. The only time it really makes a difference is at WOT.

Try this out.
http://www.go.jeep-xj.info/HowtoTBboring.htm