I know the IAC question have been beat to death but what should you see at idle with a 383, cc306, 52mm tb? I seem to still have a high iac reading and is it bad to have the iac in the 100s but still functioning? Thanks.
Rob

 

ttt

 

My 383, w/LE1 heads/cam, IAC counts runs in the low 40's. The throttle stop is backed all the way out and it idles at 950. This is with a bored out (52mm) stock TB and the TPS set to .63V.

 

well, 100's? not good

0 is all the way closed, 128 is all the way open, normal/stock ussually puts it near 28, but I would say at least halfway between 0 and 128(64), a little lower prefered

 

Actually, I believe 160 is all the way open.

 

i think your right, whatever, the other stuff stands

 

Ok..so is it a cleaning thing(iac) because it ran the same on my stock 48mm and now on the 52mm? The idle is fine around 950 and the tps is at .62. Thanks for any more info. Also, does it hurt anything to have the iac read high the way it does. Thanks.
Rob

 

My IAC is at around 75-80. As far as the high IAC it is only bad if you are geting split BLM's. If your BLM's are correct I don't see the problem but perhaps someone will have a better answer.

 

Is the 52mm aftermarket? Many aftermarket do not have an IAC bleed hole which causes either the IAC to have to open too far or people use the stop to open the blades a little which results in an OK idle but if you would just dril the IAC bleed the idle is much better.

I went through this with a used BBK 58mm I bought the former owner had opened the blades a little too get the idle IAC counts down, I was unhappy with the roughness of the idle like that and did some research and found out about the IAC bleed hole thing and it greatly improved idle quality.