Blocking IAC on LT1 and re tune

Mark Yacavone · 12-30-2023, 01:55 PM

Quote:

Originally Posted by Larry Hill

Might want to check with tech if the IAC adjuster replacement is below the throttle blades. The replacement could be viewed as an adjustable vacuum leak. Sometimes tech thinks a little differently than the racer.

I got bounced at Englishtown, in the early days of EFI for this sort of thing. The car builder was using an auxiliary petc o ck bleeder to control the idle. The IAC was disconnected and dead closed.
Lang and co. had to call CA. for a ruling. They were told that the idle vacuum air had to be controlled by the computer, or not at all. It was okayed in Div 2 ,at that time.

My Escort has an idle screw added instead of the stop screw on the throttle blades.
(IAC disconnected) It works fine with the mild camshaft.

SSGN · 12-30-2023, 08:19 PM

Just curious to why you remove the AIC and the benefits of this? I have Turbo Buicks and still use them with no ill effects. I know our cams are tiny in comparison to a stocker.
Thank for this post,very interesting.

LS1Racer · 12-31-2023, 01:37 PM

I can only speak for my case so take this for what it is worth. My idle would race sometimes and was extremely wonky. I probably could have tuned it better but have read here many times from respected racers to just unplug it or block it. I chose just to block it. I do have another TB that still has an IAC on it if I decide to go back to it.

12-30-2023, 08:19 PM	#2
SSGN Senior Member Join Date: Feb 2006 Posts: 645 Likes: 132 Liked 140 Times in 51 Posts	Re: Blocking IAC on LT1 and re tune Just curious to why you remove the AIC and the benefits of this? I have Turbo Buicks and still use them with no ill effects. I know our cams are tiny in comparison to a stocker. Thank for this post,very interesting. __________________ The more people I meet the more I like my dog Kevin

12-31-2023, 01:37 PM	#3
LS1Racer Junior Member Join Date: Feb 2006 Location: Westminster, CO Posts: 56 Likes: 5 Liked 6 Times in 6 Posts	Re: Blocking IAC on LT1 and re tune I can only speak for my case so take this for what it is worth. My idle would race sometimes and was extremely wonky. I probably could have tuned it better but have read here many times from respected racers to just unplug it or block it. I chose just to block it. I do have another TB that still has an IAC on it if I decide to go back to it.