8.1L 80mm TB questions

[CHEVYHD496]

i have the BBK 80mm TB to put on my truck. i have seen the idle sticky and i saw where it said unless its a bigger TB the effective IAC area has to be changed, but it didnt say or that i noticed how to change that. would that be table B4403? and how would you convert sqaure MM into IAC steps? thanks for the help

[CHEVYHD496]

anyone? ideas? vehicel is my sig

[CHEVYHD496]

am i missing something? or, how do you adjust for a bigger throttle body?

[Aloicious]

IAC effective area is going to be quite difficult to adjust properly, I've tried playing with it before but always end up coming back to the stock settings....I also have an 80mm TB on my L31, which I'm currently using the stock IAC effective area table on quite successfully. the larger throttle body alone won't affect the tune TOO much, the main thing I had to adjust for when I installed it was the TB blade set screw, to make sure my IAC steps were appropriate (~60-80 steps at warm idle is where I like it for my setup). but thats more of a mechanical issue rather than tuning, mainly for the tune, you might want to run a few autoVE and autoMAF runs to be sure everything is where it should be, but theoretically, the larger TB shouldn't change the VE TOO much.

[CHEVYHD496]

ok, well im trying to figure out then what to do to run it. would i need WB02's to get this thing to run right? any other tips would be helpful

[Aloicious]

well, Ideally, yeah you want to get a wideband to get all your fueling and airflow tables correct, but thats universal, not really just for your TB...all in all, I doubt you'd have much problem just running it after correctly setting the throttle blade set screw...what's the stock TB on the 8.1? 78mm TB's are stock on many LSx. on the late vortec gen1e small blocks, they were 75mm stock IIRC...really 2-5mm isn't going to make a massive amount of difference. this thread may help you out a little;
http://forum.efilive.com/showthread....9281#post99281