What size to drill out the TB?
Thread Starter
Administrator
Joined: Nov 2001
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From: Houston, TX
What size to drill out the TB? What size drill bit did you guys use to drill in the throttle body for the idle fix after your cam installed?
I've heard some different sizes out there, so please list what cam and M6 or A4.
Thanx in advance,
Craig.
I've heard some different sizes out there, so please list what cam and M6 or A4.
Thanx in advance,
Craig.
TECH Senior Member
Joined: Nov 2001
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From: Troy, AL
Re: What size to drill out the TB? If you have Autotap just start small and work your way up one small step at a time 'till you get your IAC pintel position correct (30-40 is good with the car fully warmed.)
You don't have to remove the TB from the car to do this. Just stuff a rag all the way back well past the TB blade underneath it. After you drill, carefully slide the rag back out and the shaving will come with it. Look carefully up into the intake with a flashlight to make sure that it all stayed on the rag.
You don't have to remove the TB from the car to do this. Just stuff a rag all the way back well past the TB blade underneath it. After you drill, carefully slide the rag back out and the shaving will come with it. Look carefully up into the intake with a flashlight to make sure that it all stayed on the rag.
Thread Starter
Administrator
Joined: Nov 2001
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From: Houston, TX
Re: What size to drill out the TB? I don't have an Auto Tap, but I think I can find somebody thats does. The rag idea sounds good plus I think I'll have a "Shop-Vac" ready too. lol
Thanx,
Craig
Thanx,
Craig
TECH Enthusiast
Joined: Nov 2001
Posts: 712
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From: Dallas,Texas
Re: What size to drill out the TB? With a M6 and hotcam I have my throttle
blade drilled out to 15/64 I have heard
some have gone to 17/64..
with hotcam and SLP lt's I still have a bit
of idle problems.. but thinking about the
trooper mod soon.
blade drilled out to 15/64 I have heard
some have gone to 17/64..
with hotcam and SLP lt's I still have a bit
of idle problems.. but thinking about the
trooper mod soon.
I can shift faster than you.
iTrader: (21)
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From: Baton Rouge, LA
Re: What size to drill out the TB? I agree with what the Colonel said above. Only thing I would do different is pull the TB off. It is 3 easy 10mm bolts and just remove it from the car. No chance in risking getting metal shavings in your motor. Only thing I would do different...
Jason
Jason
TECH Senior Member
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From: Troy, AL
Re: What size to drill out the TB? Oh, I agree. That is the absolute safest way and the TB does come off easy. Just giving an option. Like I said, if you do it that way you should look carefully into the intake with a flashlight to make sure that there are no shavings.
[ November 18, 2001: Message edited by: Colonel ]</p>
[ November 18, 2001: Message edited by: Colonel ]</p>
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TECH Apprentice
Joined: Nov 2001
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From: Tucson, AZ
Re: What size to drill out the TB? I just got a YANK ST3500 and my idle is too high and as a result it throws a code... should I drill out the hole or can you adjust the alan bolt in the hard stop?
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Verdad Gallardo TECH Senior Member
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From: Troy, AL
Re: What size to drill out the TB? The ECM via the IAC controls the idle rpm but you might make sure the screw you mentioned (it's actually a star head screw) isn't screwed in too far for some reason. Check the TPS. It should be %.4 or less.
You should also do the idle relearn procedure.
You should also do the idle relearn procedure.
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From: Tucson, AZ
Re: What size to drill out the TB? What is the ATAP "gauge" that tells you TPS Voltage?
I know at idle, ATAP says for Throttle Position 0.0% and at full throttle 100%... but I was under the impression that I'd get degrees of the butterfly opening and as I understand it's not to exceed 89 degrees or there's too much voltage... right? Is there anything in autotap that tells me how much it's opening at WOT?
Will playing with the start bolt on the hard stop have any negative effect?
I've tried to have the computer learn but it's no use... I've cleared the codes numerous times and pulled the fuses and reset it several times and the codes just keep coming back. The converter has been in for close to 2 weeks now and I've logged on probably 200 miles or so and the codes still keep coming... so I'm convinced something needs to be done.
I know at idle, ATAP says for Throttle Position 0.0% and at full throttle 100%... but I was under the impression that I'd get degrees of the butterfly opening and as I understand it's not to exceed 89 degrees or there's too much voltage... right? Is there anything in autotap that tells me how much it's opening at WOT?
Will playing with the start bolt on the hard stop have any negative effect?
I've tried to have the computer learn but it's no use... I've cleared the codes numerous times and pulled the fuses and reset it several times and the codes just keep coming back. The converter has been in for close to 2 weeks now and I've logged on probably 200 miles or so and the codes still keep coming... so I'm convinced something needs to be done.
TECH Apprentice
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From: Tucson, AZ
Re: What size to drill out the TB? TTT - Anyone know if adjusting the torx-head bolt in the hard stop will have any negative effect? For the idle being too high as it is, I'd want to drive the bolt in further to have the throttle butterfly slightly open at idle, correct?
Another question, could a mass airflow sensor cause this problem too? It dawned on me that I installed an SLP mass air a few weeks before the converter. I installed 02 simms to silence my clogged cats (that come out tomorrow anyway) and then this SES light presented itself but I'm unaware of whether or not it was there before... I will probably swap back to stock to see if that is what is causing it, but COULD an aftermarket MAF cause this "idle too high" SES light?
Another question, could a mass airflow sensor cause this problem too? It dawned on me that I installed an SLP mass air a few weeks before the converter. I installed 02 simms to silence my clogged cats (that come out tomorrow anyway) and then this SES light presented itself but I'm unaware of whether or not it was there before... I will probably swap back to stock to see if that is what is causing it, but COULD an aftermarket MAF cause this "idle too high" SES light?
Re: What size to drill out the TB? There are two ways to raise the idle:
1) Raise the set screw (torx 15). I think you can only raise it about 200 rpms before it sets an SES lite due to the idle speed being higher than the pcm setting. Also too much and your TPS voltage can get too high and also set an SES lite. I don't like to have the TPS voltage higher than .7 by doing it this away.
2) Drill out the TB air hole. Too much and you have to epoxy it.
I have a combo of both for my car.
1) Raise the set screw (torx 15). I think you can only raise it about 200 rpms before it sets an SES lite due to the idle speed being higher than the pcm setting. Also too much and your TPS voltage can get too high and also set an SES lite. I don't like to have the TPS voltage higher than .7 by doing it this away.
2) Drill out the TB air hole. Too much and you have to epoxy it.
I have a combo of both for my car.