I take it all of you have already enlarged the hole in the throttle blade?

 

no, you're not suppose to

 

x2....

 

Makes a huge difference, I have never seen anyone thats done it have an issue. There is no way that a little hole like factory can flow enough air for a large cam. I have seen that method fix several trucks idleing issues.

I do agree that they say ur not supposed to on a dbw tb.

 

We have idle air control valves for a reason......

 

I think if your tune is setup correctly you should not have to do this... Like I mentioned above, there is alot of tables/parameters that contribute to vehicle idle... Drilling hole method was used alot in Carb setups, when they did not have as many adjustments as modern EFI systems, IMO it just got carried over...

 

hey corey, what do you think about that comparison i posted up about turning up the iac?

 

What I am getting at is they are not designed to handle the amounts of air that a cammed engine needs and this helps. I have seen several people do it, including some big name tuners, Im not arguing just saying.

 

Theres a certain area the IAC motor is designed to operate in, that and the tb are setup for a stock motor. When we hooked a scanner up to mine the IAC counts were really high, we drilled the hole a little bigger in the tb and it brought them back down close to stock levels.

The IAC motor can only open so far to let air in.

 

Are you using HPTuners? If so, I slapped together a little write-up / How 2 for idle tuning a cam that you can follow:

http://www.silveradoss.com/forums/in...=0#entry574851

It should get rid of your issues however as mentioned above, if you have a mechanical issue (i.e. leak) it will just mask it.

Good luck