I am interested in porting a throttle body, about how much does it cost and is it worth? Should I go to a 52mm? I have a 94' z28.

 

a bigger throttle body is not needed on a bolt-on car. i would look for power elsewhere.

what other mods do you have?

jesse

 

i thought getting up to a 52mm TB would help a bit cause the ports on a stock intake manifold were 52mm wide

 

I agree, a bigger TB at this point would probably do you little to no good.

(To help others assist you, post your year model along with all your mods in your signature field under your profile. )

 

the 48mm TB flows enough air for stock/bolt on cars.
by upgrading to a 52mm, you would gain less than 5rwhp.
jesse

 

The stock TB is probably not a source of restriction for you at this point.

 

so just out of curiousity, when is it neccessary then to get a bigger TB?
forced induction? n20?

 

this topic is debated here frequently. do a search.
IMO the stock Tb is good enough for 375rwhp, then you can start thinking about upgrading.

jesse

 

there are my so far mods.

 

I would definately worry about getting power from something else... stock cam? stock heads? injection? inside of your motor bone stock ? sounds like you don't have much done on your motor... i'd start getting some parts