blkbird

iTrader: (28)

I am going to install the hotcam in my engine in a couple of weeks. My question is if I would have to drill out the TB to make it idle better or will this cam idle without doing so? Thanks

pla-tym

you can adjust the idle stop set screw on the TB instead of drilling the throttle blade.

zspot98

iTrader: (87)

You should never have to drill into the TB anymore than GM did when they sent it out. Either adjust the TB blabe to allow more airflow in @ idle or get a good tune. Just my .02

blkbird

iTrader: (28)

Cool! Thanks for the input.

2xLS1

iTrader: (25)

https://ls1tech.com/forums/pcm-diagnostics-tuning/440075-those-you-belive-shifting-iac-table-correct-its-not.html

blkbird

iTrader: (28)

So is this something an experienced tuner should take care of? Sounds complicated.

TARZAN

iTrader: (12)

Mine is drilled, and the car idles fine, with a Comp custom cam, and no tune....Don't mess with that set screw

-Will

blkbird

iTrader: (28)

What size did you drill the hole to?

MeentSS02

iTrader: (11)

Drilling actually IS the correct way to deal with the problem. You are best off drilling a completely separate hole though, starting really small, and work your way up from there. Drilling out the existing hole could lead to it ending up being bigger than you really want.

SgtB

iTrader: (3)

adjust the set screw do not drill.
drilling is an old method and is highly frowned upon

radkon

iTrader: (2)

Drilling and/or adjusting the set screw is the cheap way out of getting a tune. A properly tuned car shouldn't need either.

2xLS1

iTrader: (25)

So explain how you are going to lower IAC counts without doing either.

radkon

iTrader: (2)

A full tune will follow an order similar to this (Set idle,set IAC, reset tps, tune LTIT/STIT's and make adjustments to RAF table, tune VE in idle area) When some shops tune a car they only tune WOT and a few other parameters. Get a full "drivability" tune and all the tables should be reviewed and edited if needed.

Grimes

iTrader: (3)

2xls1 is correct
sometimes you will need to drill the blade or mess with the screw, even if you have a tune. this is in order to get the right IAC count - it may not be possible unless you do one of the two

blkbird

iTrader: (28)

So, should it get tuned first and then drilled or vice versa?

2xLS1

iTrader: (25)

IMO drilling the TB if needed to get the IAC counts in line is part of the tuning process.

blu98ta

iTrader: (4)

When we did my buddies cam we drilled the hole and then got it tuned. Of course with a bigger cam the car is going to want more air at idle, so you need to allow it more air by DRILLING THE HOLE. Don't mess with the screw. If you do that then you are just opening the tb. Drill the hole. I'm not sure what the stock size is, but go at very small increments, it wont take much especially with the hotcam.

zspot98

iTrader: (87)

Isn't that's what that screw is there for? I mean if you drill too bigg of a hole than your TB is ruined IMO, but it you adjust the blade itself not too much damage can be done. Wel besides messing up the AF ratio. I agree w/ SgtB on this, there is no need to drill the hole when you don't have too. Just my .02

blkbird

iTrader: (28)

Im so confused. What is the right method??

blu98ta

iTrader: (4)

Drill the hole!!