I recently purchesed a slightly used NOS Holley 58mm TB, as seen here.
http://store.summitracing.com/partde...5&autoview=sku

It didnt come with any gaskets or sensors. So i'm guessing i need to remove the stock coolant crossover, TPS, and IAC motor and transfer it over to the new one. Is this correct? Can i just pick up new gaskets at an auto parts store or would I need to order them? If I need to order them, would a BBK set like seen here work. Or would I need Holley/NOS specific gaskets, and if so, where would I get them.
http://store.summitracing.com/partde...700+115&orig=1

The stock size/style tb plate and coolant crossover gaskets should be the same, so those should work, but the TB to intake manifold gasket will have 58mm bores, which i'm sure a local parts store will not have. Is there anything else I should do like replace the TPS and the IAC, or should I just clean and reinstall them. I already plan on boreing the stock 52mm intake manifold bores out to 58mm.

Please let me know cause i want to get this done over thanksgiving weekend.

 

i have a bbk 58mm, jsut transfer the sensors over, make your own gaskets, i had to after accidently tearing up the ones from BBK.

 

So do all aftermarket throttle body's use the stock coolant crossover? Does anybody make one that deletes the coolant passage so its just the mount for the IAC motor? Im just trying to clean it up a bit.

 

I don't see why couldn't just leave off the coolant crossover and not worry about bolting it on...whats the difference in just leaving it off, or mounting it and not connecting the hoses if its been by-passed already...I don't recall anything else being under there that needed to be sealed off??

Everything else just swap over, pick up the gaskets at the local parts store and cut them your self with a sharp razor blade using the TB back as a pattern with the gaskets lightly taped or lightly bolted to the back using the install bolts to hold the gasket in place while you trim it around the bores.

 

You can't leave the bottom plate off the throttle body. In addition to the coolant passages, it houses the IAC motor and seals the IAC passage.

My Holley came with a new 58mm gasket.

The bottom plate gasket comes in a "kit" from GM, along with a top plate gasket. Shoebox has the part # for the kit on his website.

 

Ahh.. I knew there was a little man in the back of my head saying there was something else under there but couldn't remeber what it was..even after all those mods I had to do to get my Holley to work right

 

For some reason my BBK didn't come with a gasket so I just used a Dremel and sand roll and went around and around until it was opened up enough. Make sure you follow directions on the IAC so it can reset itself or you will have idle issues.

 

One more question. How much should I port on the IAC houseing/port thing?
The thing that kind of sticks out here.
http://www.bfranker.badz28.com/96ss/Port16.JPG
http://www.bfranker.badz28.com/96ss/Port17.JPG

Should I leave those little "ears" alone or should I match it with the rest of the porting?

 

My LT4 intake was bored to 58mm and fully ported by CNC Cylinder Heads. They cut the "ears" back quite a ways. If you want, I can e-mail you a photo.

 

That would be great. Send them to kcmtrh@***.net please. I ground them down quite a bit anyways. Sits about flush with the TB foil.

Now I have a new problem. When i blip the throttle, the blades don't close all the way, it acts like something is binding. It usually sits at about 1-3% throttle after I let off. My stock TB was at .62 for the throttle position sensor, this one is at like .78. Is that something I need to adjust or is that whats causeing the open throttle?

 

Ha, welcome to the Holley TB world!
Check this thread..its what I did to make mine work. For the TPS, you have to slot the holes on the sensor so you can rotate it just a bit to get the idle TPS down.

Read this entire thread as I did several things then changed a few at the end and posted some links to some pics.
http://web.camaross.com/forums/showthread.php?t=474431

 

Heres' a pic of my LE port job on the front IAC back part, and the TB is bored to 58mm as well.
http://hometown.aol.com/onebadwskier...4-intake11.jpg

 

Alright, I slotted the TPS and got it to the correct TPS.

I also sanded down and polished the edges of the TB plates so they dont rub anymore. I polished the points where the shaft makes contact with the houseing and put some grease on the contact points too.

Still, the throttle wasn't closeing completely when the car was running, so I drilled a hole on the side of the houseing for more spring tension, as seen in this post.
http://web.camaross.com/forums/showthread.php?t=474431
Now I think my TPS sensor is going out because no matter how much I move it, it stays at .02.

So hopefully I can pick one up at the parts store tomorrow and everything will finally work.

 

Taken from the other thread:
I run the LPE/Accell and yes all the routing/plumbing is like stock. The only issue I had is it getting stuck at WOT three or four times when it was new. No idle issues. VERY quality piece, however as Fred pointed out it's expensive, but after reading this stuff it's well worth the cost. I opted to get an adjustable TPS with the TB.