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All right. I'm about to attempt to put a hole in my throttle body. My question is where the hole goes. I do not have my stock tb to reference. Is it on the very bottom of the tb or put it between the blades on the bottom? Pretty sure I'm maxed out.
if you are talking LT1 TB...you drill the hole between the blades. lower front center part of TB
IDK what function your scanner is reading...you want to read IAC counts. They max at 160 IIRC. You want them 32 (30-35) at idle with engine at operating temp.
you need a scan tool that reads IAC counts. drill 1/8" hole, scan IAC. If still to high drill 1/64" larger. TAKE BABY STEPS, 1/64" makes quite a difference
do not blindly drill a hole without being able to scan for IAC counts
Between the blades towards the bottom. I would only drill if you have a dedicated IAC passage (like stock) on your throttle body. A lot of aftermarket ones don't and if that's the case then you can just crack the blades.
if you do the crack the blade thing on a aftermarket TB to resolve low IAC (usually H/C builds) than you need to "adjust" the TPS to bring vdc back into spec
There is a write up on this on Golen Engine site IIRC. Involves slotting the 3 holes on TPS so you can "clock" it back to then read correct vdc. This is more important on auto cars vs T56 as the PCM gets data for line pressure from TPS for automatic cars
I have a professional products throttle body. I've looked through my scanner several times and find nothing for ICA counts. Now should I drill an 1/8 hole for starters and no bigger just for the fact that the factory had it but not knowing my ica counts? The car will not idle with the AC engaged. On the highway its fine, but if you come to a stop it will kill it. Also if you brake hard at highway speed, it comes close to kill the engine but doesn't.
Here's why drilling it wouldn't do anything more than cracking the blades open. See the arrows? No dedicated IAC passage as it connects directly to the plenum.
Crack the blades until the IAC counts go down and the motor doesn't die anymore. If the throttle position goes above 0 when closed then file the TPS sensor holes so you can rotate it and reduce voltage. I think the threshold is around 0.8-9.
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throttle body hole 
