I am a Moderator on a different site, here is a couple of posts on the 4 corner idle mod:
"Agree that you need to be very careful when you drill the main body for the
secondary idle circuits. Seen several carbs where guys drilled right thru the carb into the venturi section
>
.
Measuring the primary depth and using the same depth will work well.
Typically the idle air bleeds need to be opened up on the secondary side too. (same as primary). When done all 4 mixture screws should be 3/4 turn out at best idle (or close)."
Tom Vaught
His Reply:
"I was hoping you were going to post up in here
Yeah you just described my setup lol. All idle air bleeds are the same size, and its the happiest with the idle screws around 3/4 of a turn out From a stone cold engine, I can pump the gas twice, hit the key, and it'll run without having to run the throttle
I could never get it setup like that with a 2 corner idle setup.... Been tuning it for like 4 months now and it runs just as good as a efi setup would
I'm very pleased :cheers: Thanks to all the info on the turboforums of course Thanks guys
Bowtie Guy"