OK....here is what I have going....my car is a 1991 Z28 Camaro 5.7 L98 TPI. I bought a BBK/Edelbrock 52MM TB off of ebay.....and just found out that it is for an 85-88 TPI model. The Throttle Body will fit fine.....but..just the Throttle Cable (89-92)....won't attach correctly to an 85-88 Throttle Body. So..a few guys have told me that I can just use an 85-88 Throttle Cable, and everything will be fine.....which..I'm REALLY glad to hear. My question is.....on my stock Throttle Body...the throttle cable isn't held in with a clip or anything like the 85-88 tpi TB's.....how do I remove the throttle cable? Thanks guys..

 

There is a little metal cylinder that is molded on the end of your cable. Just work the cable over the arc and slide out the cylinder. It's hard to explain in words, but a very simple process. Remove your 4 throttle body bolts if you have difficulty seeing the mechanism or if you can't free the cable to rotate it.

 

Thanks JMatlock88.....I'm going to go to my local GM dealer tomorrow to see if I can get the 85-88 cable..and the little clip to go witih it.

 

Sure! Someone mentioned that they carry them at NAPA too? Might be cheaper unless you have a shop discount at your local GM parts dealor. Good luck to you!

 

you got a 85-88 TB. yet you have a 91 TPI setup, I'm sorry to tell ya but if I'm not mistaken it won't work, the air idle passages on the TB are different on a 85-88 TB than a 89-92 TB.

I know this because I have an 87 TPI car, and when I got my SLP runners I ordered a set of 89-92 runners. I tried to use the runners with an 89-92 plenum & an 85-88 TB and it didn't work, the idle air assages are totally different and the car wouldn't hold an idle for the life of me.

I had to replace the TB w/ an 89-92 to make it work properly

So you you will probably have the same problem I had.

I hope you have better luck than I did.

 

Hmmmm....that is weird..... I talked to JMatlock88....and he had no problems like that, he just changed the throttle cable....and it was fine......

 

check the back of your TB and the after market TB, if they look the same then you dont have a problem, if they look different, then you have a problem heh. I'll look for some pics to better explain.

oh yea, and I had to change my TB cable to fit the 89-92 setup.

 

I don't have my TB off yet.....I just ordered the Throttle Cable today..so....I'm not sure yet....some pics would be great.

 

OK

Here is a pic of my old 85-87 plenum, the triangle hole in between the TB butterfly holes is what the IAC sensor uses to idle.

On the 89-92 plenums, there is no 3rd triangle hole, just the 2 butterfly holes. The 89-92 TB's IAC has been modified to use a different idling setup. This is why I couldn't use my old 85-87 TB on the 89-92 TPI setup.

I don't have pics of the TB's or else i wouls show ya.

I hope you get a better understanding as to what I'm trying to say

 

So 5SIZ....if I change the TB....without hooking any cables up...and control the throttle with my hand....it should tell me right then if it will work properly right? I just don't get it how some of the guys have changed their TB's over..and didn't have any problems....oh....and would someone get the same results if this would be done?..vice versa?...85-88 TPI with an 89-92 TB.....89-92 TPI with an 85-88 TB?

 

well when I tried it with the 87 TB it would start up and die, but if I would start it up and start giving it gas, since the throttle blades would open the car would stay alive, but barely & when I would stop giving it gas the car would just die.

I have no idea what everyone elses experiences with this are.

Maybe the after market TB are universal? who knows, I'm just giving you a heads up so if you get this problem then you will know exactly whats wrong.

let me know what happens.

 

Well...I think I'm just going to go ahead and sell it. My car is running very well right now...and I don't want to mess anything up. There is one guy that is interested in the TB...so..I'll give him an email. I wish I would have known about this earlier though....I just bought a brand new Throttle Calbe today for the TB....guess I'll post it up forsale. Thanks for all your help man.

 

if you want to try it out for the hell of it, then go for it.

 

Look at the back of your aftermarket (BBK) throttle body. The throttle body should have a hole in it in the place that matches the triangle plenum hole that 5SIZ posted. It should also have notches cut from this hole to the big twin bores. This allows the aftermarket throttle body to be universal. Hence it will work with or without a triangle penum hole. All you need is the cable.

If you want to swap an old style stock throttle body onto a newer style plenum, you do not have the hole in the plenum. Hence, all you need to do is drill one. A circle hole works fine (instead of triangular).

 

So IT IS universal, that clears everything up

 

Yep! . . .hope you didnt already sell it!

 

This still isn't making much sense to me....lol..sorry!! Ok.....here is a picture....I see exactly what your talking about (the notches in the twin bores).....what are the notches used for? I haven't taken ANYTHING apart yet....and probably won't for a little while...I'm hoping I can do this successfully...I'm not much of a mechanic at all. And...nope..I haven't sold it yet.....I just don't want to mess anything up....and JMatlock88...you did the same exact same thing to yours too right? I mean...adding an aftermarket 85-88 52MM TB to an 89-92 Plenum? And it was fine? Right? sorry if I'm repeating myself.....i just want to make sure...I'm not digging myself hole here....

 

The notches allow the idle air to pass through the triangle shaped hole or through the twin bores if there is no triangle shaped hole.

No, I just know what I'm talking about.

I run a stealth ram. It's plenum does have a circular hole between the bores, so it can be used with either style of stock throttle body. That's becide the point.

You're not digging a hole, just rest assured that your TB will work fine with a simple cable swap. They designed it this way on purpose to save money. (so they dont have to make two different castings)

 

Agreed to JMatlock88. After seeing the picture of your TB it is machined to work with both stock plenums. I imagine the only reason BBK speifies 85-88 and 89-92 is that they accomodate the cables different. get the cable to work and your all set.

 

That's great to hear that someone did second what JMatlock88 has said! I know the 52MM won't really do much....as fas as power, performance, or anything....but..I hand polished it, and it will be a good addition to my exsisting TPI set-up.

 

Well..a friend and I installed my 52MM TB today....and..we have a problem....it idles...BUT..it idles...WAY to high and my check engine light came on....? Does this make sense?? I thought maybe it was the TPS....I took the TPS off of the 52MM TB when I polished it....thought maybe it wasn't set right. OR...is it just because this TB is for an 85-88..like we were all talking about earlier....? I mean.. the back side looks just like my factory TB.....

 

You need to go through the procedures for setting the TPS and IAC/minimum air as described in the technical articles. Take care not to crush the pintle while screwing in the IAC when it's fully extended.

 

What is this "pintle" thing?..I've been printing off on how to set the TPS and the IAC.....there is noway that I can mess anything up is there?

 

The cone shaped end of the IAC.