pcmhacking.net

i found this online. may help with you cammed ls1 owners

Thanks for posting, Ive added this as as sticky so it'll remain findable.

Can someone explain this a little more for me please.
As I have a cammed L67 with the LS1 TB and wonder if it might be helpful in some way.

Cheers

i believe what this is referring to is the hole in the throttle blade of the throttle body, which will constantly bleed air into the motor.

if you chuck a big cam in the engine and it needs more throttle opening to idle (or in this case IAC open) then you can use that to calculate the hole needed to be drilled in the TB to get the IAC back to the right setting.

big cams also tend to have less vacuum and because of this are more prone to stalling and having idle issues if the air bleed is too small, add to that if you actually open the throttle stop too far it will go out of idle mode because the TPS will be reading 1-2% open.

i've also found this to be a bit of an issue in my race car where i do have a large cam and also have no PCV (air bleed) so theres less air leaks in the system than normal, so needed to put a small hole in the buttlerfly.

Thanks for that. Makes sense now.

I have downloaded the attachment, but can't seem to get any input on to it ? What am I doing wrong, maybe it doesn't work for a tablet.

At the top of your excel screen in yellow you need to click enable editing. Should work then.

Ok thanks, will give it a try.

I have a VS V6 cammed L67 with a Kalmaker Map Tune, running a LS1 TB.
Can I use TunerProRT to scan & read the IAC steps at idle ?

if there is an ADF for the version of code your running then yes.