Hey Guys,


I have a 1991 Z28 5.7 Tuned Port Injection (L98).....and I was just wondering if a BBK 52 MM Throttle Body is worth the money and what it really did. Some of my buddies said that they've had the BBK 52 MM Throttle Bodies on their 5.7 TPI's and they said they are worth the money and they noticed a pretty big difference. So.....what do all you guys with 5.7 Tuned Port Injection think about these? Thanks!

 

The sealed roller bearings on the throttle shaft are nice, stock TBs have bushings which eventually wear and cause the shaft to bind..."why does my car idle at 1500rpm" kinda thing.

The machined/cast inlet area gives similar airflow benefit to an airfoil.

I ran a stock TB bored out to 52mm by SPD (www.spd.com) for years, replaced it w/ a BBK because the throttle shaft/bushings wore out and it was binding. I solved it with an additional return spring for another year, eventually it started binding again.

 

I have a 52mm bbk t-body I noticed a pretty good difference vrs the stock.The only thing I don't like is how the foil doesn't go all the way out to the edge.Either way you won't go wrong with one it will help.Good luck

 

Not worth the money unless you already have other mods, headers, exhaust, etc.

 

Not worth it unless you have other mods.....

example:
GM's ZZ502 is a 500 horsepower 500 cubic inch big block. They use a 48mm throttle body.

 

https://www.thirdgen.org/techbb2/sho...hreadid=134163

 

A lot of people (a LOT) have found the BBK to be a poorly made unit that caused them a lot of problems. Others have had no problems. I decided to spend $50 more and get the billet aluminum holley, and it's a top quality piece.

 

Get the Holley if you decide to go with a TB

But I would honeslty spend hte money else where like on a good Cam or Headers

 

I've had the BBK 52mm for over 2 years, no prob. On a stock motor don't expect a gain though.

 

As far as the engine goes in my 91 Z (5.7 TPI L98), it's basicaly stock.....as far as I know anyways. I have 3 inch cat back 80 series flowmaster exhaust, 3 inch exhaust cut out with both cat's removed. I wouldn't mind to put a cam or headers on....but....I have no idea how to do that kind of stuff......I'm more of a paint and body person. If I can get someone to do some stuff to my engine, I'll do that. But...I just wanted to see id the TB done anything on a stock 5.7 TPI.