Drilling the throttle body. Need help ASAP!!
Thread Starter
Launching!
Joined: Feb 2002
Posts: 210
Likes: 0
From: miami
Drilling the throttle body. Need help ASAP!! Antone else how has an aggressive cam and had to drill the throttle body please post what size hole you used to drill into the throttle plate.
I just installed a pretty agresive cam and I have been trying to use ls1 edit to make her idle well but I just cant get it to work. My mechanic recomended that I use a 1/8" hole but other guys I have talked to have used a 5/16" hole.
I want to get a feel for what size hole you guys have. Please post ASAP because I wont to do this mod today.
If anyone has any other trick to get her to idle well please let me know.
Hear let me describe my situation:
I can start her fine without my foot on the gas, she idle normal when cold and hot. But when I rev up the engine and the RPM come doen they go below the normal idle, 200RPM's, and she sometimes recovers and stays on but most of the time she turns off.
What Iam guessing is that the throttle body does not open fast enough when the RPMs come down to the idle spot. Due to the agressive cam the engine asks for more air than the throotle body can supply as the RPMs come down. So if I drill a hole it will let the engine breath a little more as the RPMs come down and she will stay on.
I just installed a pretty agresive cam and I have been trying to use ls1 edit to make her idle well but I just cant get it to work. My mechanic recomended that I use a 1/8" hole but other guys I have talked to have used a 5/16" hole.
I want to get a feel for what size hole you guys have. Please post ASAP because I wont to do this mod today.
If anyone has any other trick to get her to idle well please let me know.
Hear let me describe my situation:
I can start her fine without my foot on the gas, she idle normal when cold and hot. But when I rev up the engine and the RPM come doen they go below the normal idle, 200RPM's, and she sometimes recovers and stays on but most of the time she turns off.
What Iam guessing is that the throttle body does not open fast enough when the RPMs come down to the idle spot. Due to the agressive cam the engine asks for more air than the throotle body can supply as the RPMs come down. So if I drill a hole it will let the engine breath a little more as the RPMs come down and she will stay on.
TECH Junkie
Joined: Nov 2001
Posts: 3,604
Likes: 0
From: Los Angeles
Re: Drilling the throttle body. Need help ASAP!! 1/4" is as big as I'd go. I had I think a 7/32" hole in mine when I had a 230/230 on a 112lsa cam.
I'd say start at 1/8", if thats not enough do a 3/16". It only takes like 3 minutes to remove the TB and you DONT want to go to big. Take your time and just step up through the drill bit sizes until it works nice.
I'd say start at 1/8", if thats not enough do a 3/16". It only takes like 3 minutes to remove the TB and you DONT want to go to big. Take your time and just step up through the drill bit sizes until it works nice.
TECH Regular
Joined: Apr 2002
Posts: 445
Likes: 0
From: McChord AFB WA
Re: Drilling the throttle body. Need help ASAP!! Here is a link that has many different cams and TB drill sizes. Maybe your cam is on there and you can duplicate their setup <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
http://xs-fx.com/raughammer/cam_info.htm
http://xs-fx.com/raughammer/cam_info.htm
Re: Drilling the throttle body. Need help ASAP!! BLU, you have a C5 and there is no set screw on our TBs. Drill the hole on the lower portion of the butterfly in the middle. Use these lists of drill bits until you get the idle to stabilize and no issues with coasting to a stop. Start with these: make sure after you drill it to do a good bit of driving around so the car can learn for the increased air at idle and adjust for it.
(increasing size from left to right)
3/16 --> 13/64 7/32 15/64 1/4 17/64 9/32 19/64 5/16 21/64 11/32 23/64
(increasing size from left to right)
3/16 --> 13/64 7/32 15/64 1/4 17/64 9/32 19/64 5/16 21/64 11/32 23/64
Re: Drilling the throttle body. Need help ASAP!! If you have Edit you can increase your IAC tables by 10 - 15% and you may not need as big a hole. Use as small as possible to get the job done.
Trending Topics
Thread Starter
Launching!
Joined: Feb 2002
Posts: 210
Likes: 0
From: miami
Re: Drilling the throttle body. Need help ASAP!! I run a supercharger on this car, Iam not too familiar with ls1 edit I just got it a few days ago so Iam new to the whole programming.
What does IAC do?
If I inrease this can I be more vulnerable to detonation?
What does IAC do?
If I inrease this can I be more vulnerable to detonation?
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Re: Drilling the throttle body. Need help ASAP!! </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by BLMONGOOSE:
<strong>Well forget about the IAC thing. I just went to try and edit that table and it tells me that this feature in not implemented for my year.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">you have a 98?? It said the same for my 98TA
<strong>Well forget about the IAC thing. I just went to try and edit that table and it tells me that this feature in not implemented for my year.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">you have a 98?? It said the same for my 98TA
