Black6SpdTA

my buddy with a 5.0 said hes got a bigger TB and a lot of ppl ive talked to have em to. if i found one off of somethin like a 350 truck motor, 454 etc would that make me faster

87DJP2001

According to many people on this form, bigger is always better. and anything bigger has to make you faster, go for it.

ZZ430RS

350 engines have the same size TB, you will have to get one off a 454 or the 670 Holley one. But unless you have a lot of mods like heads, cam and headers it's not worth it.

aklim

A friend of mine with a stock vette dropped a 58mm TB into the car and it ran about a tenth slower in the quarter. I think it disrupted the airflow because it was not properly matched to the rest of the engine.

kandied91z

you have to match them...........unless your 400+ i wouldn't.

Blownyellow

I am running over 700 to the wheels with a 52mm throttlebody. I always try to advise against running anything more than a stock throttlebody up to at least 400 horse. It really does sound funny, but the fact is that aftermarket companies made a solution to a question that no body asked. I agree that if you want to make over 500 horse off a stock t-body then your strechin it, but the fact is that there are WAY may problems in your way before the t-body becomes restriction.
I am running a forced induction engine, and that is the reason I can get away with my power output, but I built 420 dyno horse on the stock t-body N/A before I up-graded.
Just take the over all diamiter of a dual blade t-body versus what a mustang over sized t-body single has making over 500 horse and you have you answer.
But I agree that if you ever have the chance to buy either a 58mm or a 52mm on a 350 or larger engine, why not take the 58 mm, it is not going to hurt you on a larger displacement engine, and it leaves room for future engines.

Jim85IROC

Blown, I think he's talking about a throttle body for a TBI car, not TPI. I agree with you 100% that the stock TPI TB is perfectly adequate far beyond horsepower levels that 99% of the readers will ever achieve.

Anyway, on to the tbi. Same deal. On a stock 305, an upgraded throttle body is a total waste of money. Personally I think tbi in general is a total waste of money on a modified car, but that's another arguement all together.

Stick with your stock throttle body and buy some headers instead.

saiyanrage

You can take a Dremal tool and cut of the ridges in your stock throttle body to increase flow.Im doing that soon myself.

Chuck!

Yea definitely just do the ultimate tbi mods to the stock tbi. Even with heads/cam my MAP is constant though all the rpms, so I dont think its bottle necking me too much. My friend greg put on on a stock heads/cam tbi and didnt pick up any HP.

Take that $200 and put it twards headers or gears.