http://cgi.ebay.com/ebaymotors/TPI-5...Q5fAccessories

I'd buy new, but I can't afford a Holley and the cheap new ones (performance products, summit) seem to stick and not work correctly, which wouldn't solve my problems (I know it's the tb sticking and lubrication only works for a week or so) . I'm worried about vacuum leaks from around the throttle shaft and a short lifespan out of a rebuilt, plus the bs on the page, but maybe they're just fine. Does anyone know about these?

 

I have been looking at that same one for months now. $350 for a throttlebody seems ridiculous that would be the type of part you'd expect to be in the $150 - $200 range max.

The way I see it is these are nothing more than bored out stock units. The stock units held up for many years before beginning to stick. If they were rebuilt properly, they should hold up for many more years.

 

I bought one and it was perfectly fine!

 

That's very true. I'm gonna try and move the throttle screw in a little more and see if that helps anything, but I think I tried that and it doesn't. Mine is also giving other problems like a rough idle at times and sometimes, rarely now though, it acts like it's going to die at times when at lower rpms. I can't figure it out totally, but I think it's either a vacuum leak at the throttle shaft or the maf, which I did clean. I figured if I replaced the tb for the sticking I'd at least be able to rule that one out.

I can't see spending $350 on a tb either, especially when they supposedly don't improve performance as a 52mm unless you have over 350 hp. If I end up purchasing it I'll let you know how it all works out!

So your's worked out? No sticking? That's great to hear. I have headers on an otherwise stock lb9. I'd much rather spend $400 on a cam setup over replacement tb imho. Thanks!

 

I posted a thread just like this one a few days ago to see if anyone had bought from this guy! Glad to see atleast one person has had a good experience with these... It's mostly because my throttle body leaks air and is causing some idling issues. 52mm won't help performance on a stock lb9 apparently.. Maybe a cammed one that's fully ported and what not would benefit...

I'm going to buy one and send them my air foil so they can match it to fit the 52mm opening.

 

from what I can read it says that you may expect horsepower levels of 100 or more on a 383

 

tpi305 I would save you money unless you have a seriously modded 305. The stock throttle bodies are good to about 350hp I believe. Spend your money else where first. Maybe exhaust or higher flowing intake or suspension.

 

Well for now I lubricated the bushings with a silicone spray I had around here and I screwed the throttle adjustment screw in a bit more. So far so good, it's not sticking any more, but within this week or maybe the next I expect it to act up again, so I'll just wait and see.

Yup, you're right, they flow like 768 cfm or something, good for 350-400 hp. I was gonna replace mine because it seems to be failing, not for a power benefit though. I chose this one because it's only $150, rather than $350, and I don't want a used one. If they had a 48mm, I think I'd go with it. I could ask him if he would rebuild mine and keep it a 48mm, but this is my daily driver and I don't want it held up.

Today I found that TPiS also has a 52mm tb, which is a rebuilt factory unit like this one. It has their logo on the top, rather than the Tuned Port Injection piece is all. They want $279 for theirs, which is a lot more than this one off ebay, but if you don't want a cheapy new one that sticks, don't want a Holley or BBK, but also don't want one from the ebay guy because your sceptical, then maybe this is one to consider. If I end up doing this, I'm going with the 52mm on ebay, but the TPiS tb may be the next cheapest, but good option.

Edit: I guess it would also be good to add that the TPiS tb seems to include an airfoil. I didn't look at it much. I don't know if an airfoil truely does anything at all, but it is an added bonus worth $30 to $50.

 

So with a fully modified 305 (AS&M runners, accel manifold, ported plenum, gutted air box, ported and polished heads, cammed,forged internals, bored 0.030, etc) would this 52mm TB free up any power for me? Would it hurt performance?

 

GMPP uses a 48mm throttle body on the ZZ502, if it can feed that engine with air, it can feed yours. I would save the money and use it for other more worth-while mods. Just my .02 cents

 

Damn lol... That's strange but okay i guess... What are our options then to fix a broken throttle body shaft?? New throttle body from GM? Probably going to be insane $$.. 150$ is pretty cheap, and if it's the cheapest alternative that doesn't hurt performance, then i'd like to grab it.

 

just buy a used one, I've got one for sale with one bolt busted off on the top plate, easy fix. the tb is not the restrictive part, it's the maf and the tpi itself.

 

Well if your old one is about to take a dump on you then ya, why not upgrade now. Then you would have it for later down the road if you ever upgrade to some serious power.

 

I think the point is he's trying to stay within a budget, and a 48mm TB is plenty big for supporting lots of power.