63 mm Throttle Body
 

I see a lot of Z owners mention 63mm throttle body as one of their mods.
Who makes it and about how much $?
How does it differ from the stock throttle body and when does this mode make since?

Re: 63 mm Throttle Body
 

The two big blades inside the TB are a 58mm size. The bore is enlarged to 63m and new butterflies are cut out and mounted up.

Cost is around 300.

The gain on a P&P plenum and injector housing set is minimal.

Re: 63 mm Throttle Body
 

That's interesting Jeff, are you saying the 63mm TB isn't really worthwhile unless there are major air flow enhancements to the heads?

Hans
:cheers:

Re: 63 mm Throttle Body
 

thats an interesting topic...i also heard that 58mm is big enough to feed a 350 cu.in,no matter what kind of mods you have...any real world results?...dyno comparo?
bj
91/1735

Re: 63 mm Throttle Body
 

I would rather see somebody put the 300 bucks towards headers than to modify the TB.

Re: 63 mm Throttle Body
 

This is what Jeff told me 6 months unless you punch the block you are throwing your money away on this TB mod.

Re: 63 mm Throttle Body
 

How about if ya give it an upper -cut !!!!!!!!!!!!!!! Sorry couldnt help my self:mrgreen:

Re: 63 mm Throttle Body
 

IMO if a 48mm TB will support a 502 CI BB the stock TB should be plenty for the LT5 even with plenty of porting. Sure, its comparing 2v to 4v but airflow is airflow.