What's wrong with drilling the TB?
 

I'm trying to fine tune my idle right now, and with my big ass cam, I've already maxed out the TB set screw. I removed it and reinserted it from the top allowing on-car adjustments, so it's not that I've maxed out the range of the screw. The problem is I've maxed out the range my TPS can compensate for.

I think I reached the maximum threshold of recalibration because now it won't recalibrate back to 0% anymore. My IAC counts are still in the 150 range even with the car fully warmed up. My question is, what is wrong with drilling the TB blade? Is it bad because it leaves no room for adjustment after it's done, or is it because it has bad properties in terms of a fluid dynamcs perspective?

I was thinking of enlarging the hole a little just to bring everything back into the range of adjusting via the setscrew. Is this a bad idea? I don't want to disassemble the TPS and realign it with the shaft unless I really have to.

In your case, there is nothing wrong with drilling the TB hole. Sounds like you need mucho air in there. The factory specifications will stretch only so far.

It's just the difficulty of undrilling it, that makes it
something to do only after tuning fails (not as a
shade tree substitute for it).

Drill it if you want. There is nothing wrong with doing it. Just go up in size slowly so you don't go too big.


Nick

You can losen and slightly elongate the TPS sensor mount on the side of the TB and twist it to get more movement, might help if you are close.