Anyone have GM manual for a C4 Corvette?

BBShark

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I need a specification for a C4 throttlebody. At idle, there is a gap between the bore ID and the plate (at the bottom of the bore). I think the only place to find this is the GM manual and it's a critical adjustment for idle air control.
 

69427

The Artist formerly known as Turbo84
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I need a specification for a C4 throttlebody. At idle, there is a gap between the bore ID and the plate (at the bottom of the bore). I think the only place to find this is the GM manual and it's a critical adjustment for idle air control.

I've got an '87 and '93 shop manual laying around. I'll try to find what I think you're looking for.
 

69427

The Artist formerly known as Turbo84
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I didn't find anything useful in the '93 manual, but the '87 manual gives a process/procedure to set the throttle blades to a setting that will deliver a "default" minimum engine speed (which I infer is in case the IAC fails closed).

I didn't find anything that discusses a gap or mechanical clearance adjustment, if I'm understanding your post correctly.
 

mrvette

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As some of you may recall, I have a hotrod '72 with LT1 injection with an HEI up top in back where GOD intended,....as sparks and water don't mix.....and so the manuals I have looked at say the idle air motor should be set around 35 is all I remember.....if that is % of opening.....sounds doubtful....but it's the count on the code reader on my 1227730 speed density hookup.....
 

BBShark

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I didn't find anything useful in the '93 manual, but the '87 manual gives a process/procedure to set the throttle blades to a setting that will deliver a "default" minimum engine speed (which I infer is in case the IAC fails closed).

I didn't find anything that discusses a gap or mechanical clearance adjustment, if I'm understanding your post correctly.

Thanks. I thought I had seen that in the factory service manual for my 90 but maybe saw somewhere else. I'm guessing you want that gap to be as small as possible without the plates binding in the bore and let the IAC control idle. I suppose if the gap is to big, the IAC can't compensate.
 
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