Steves396lt1

Has anyone doen the modification on afteramrket throttle bodies where you close off the IAC area, then insert a copper tube to direct the IAC to the part of the manifold that actually feeds the idle holes?
If so, what size drill bit did you do to the throttle body? I have used a 11/64 due to an article here, http://www.chipsbyal.com/ (theres a section for LT1/4 idle quality with pics etc), and here http://para.noid.org/~lj/ in PCM tutorial.
I know the 93 speed density computer doesnt allow a funcion to comensate when the AC is turned on to assist/compensate when big cammed (mines a 230/236) idle functions. My IAC is maxed when AC is turne on and the engine stumbles and then dies. Without ac the car runs 75 IAC counts at 900rpm idle. Supposedly the IAC fix allows more air into the IAC passage to compensate for the extra fuel going in when ac is turned on.

sweetride45

I'm still building my 383, but I've done the "Brass tube" and "Aluminum Filler Piece" to my AS&M 58mm already. I'm hesitant to drill a hole right thru the thing, even though stock had it. I'm not sure if I should see how it idles and runs first, or just drill it and be done w/ it. I think I'll see first. I DO see the need for the tube/alum. piece though, to isolate the IAC passage.

Steves396lt1

I would wait. The 93 PCm is very unforgiving in idle mods, and the 94's there is a forward fee function that can help compensate for heavy mods.