Quick Question i have a stock 91 350 camaro if i get a 58mm throttle body will i see a difference in horsepower? or is it to big for stock

 

Thatd be a waste of $ on a stock car. Start with (headers/y pipe) exhaust and CAI.

Until youve got H/C the stock tb really isnt restrictive . (ram jet 502's run 48mm twin bore tb's...)

 

a 58mm throttle body will do nothing but hurt your bottom end.

Rather then get a 58mm throttle body, go for a Airfoil in the stock 48mm. Adds an extra 50cfm of air flow. (would be about 850cfm).

Theres no way you need anymore then that if you are using the stock TPI set up, as you are limited by runners/base/plenum flow.

Hope this helps,

Sheldon

 

Before you worry about getting more air INTO the engine, you should make sure you can get more air OUT.

As I understand it, a rock stock engine cant USE the additional air from a larger TB, because it technically cant use all the air it can get from the 48mm.

Now, if you intend on doing a whole slew of modifications and such, so that someday the engine will be able to use the additional air...sure...why not...

 

well i can get a good deal on one 100 bucks but i have to trade my stock one and was seeing if it was worth it

 

Nope. Not worth it.

 

It is too big for the stock plenum. You would have to remove the plenum and hog it out so that the air passages would line up.

 

Just because the ram jet 502 has a 48mm TB doesnt mean it wouldnt do better with something else. But on a 350, likely a waste until you've done quite a bit to the engine.

 

i have a 1991 Z28 5.7l TPI

already got instaled

dynomax headers don't now the size
2 1/2" tube with "Y" pipe
and flowmaster

a set of stock heads ported
MSD ingnition Coil
8.8 Accel spark plug wires
iridium spark plugs


how mouch and air foil help in my setup , or be better to get a new TB??

 

With the modifications you have, neither will do a whole lot. If you put your car on a dyno, or ran it at the track, you may possibly see a minimal difference, but I doubt you'll really be able to feel any difference.

 

I was under the impression that a stock 48mm tb flows 630 cfm.

 

wha't do you recomend me to my set up

new intake manifold ?

modified prom?


the car also has
auto 700 transmission with B&M Shift Kit
and 3.27


what you think??