Hey everyone i got a 88 gta with a 355 tpi i built i recently did a t5 swap an while i had it running at idle it doesnt wanna idle any lower then 1100 i wanna get it down to 700-800 rpm. Yes im still running the auto prom an ecm but i have a couple of my friends that have the same conversion an they got there idle down to about 800 rpm without a tune dont know how but they did. Maybe my timing is to advanced what should basic timing before top dead center be for the t5 setup maybe this will work ????

6*

Lottsa possibilities
Have you tested for and confirmed no vac leaks anywhere: a major cause of high idle
Have you set the min air and idle speed ( the proper way , not just playing with the screw on the TB ) correctly ?
Cleaned the TB and IAC recently? if the IAC is gunked up it can't operate properly to control the idle

Make reasonable offer

Thanks, Pat

Posting a .csv or .xls* log would be helpful.l