PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

how to fix bucking

Thread Tools
 
Search this Thread
 
Old Oct 6, 2004 | 05:44 PM
  #21  
The Dragon's Avatar
TECH Addict
iTrader: (6)
 
Joined: Nov 2001
Posts: 2,099
Likes: 0
From: Tampa, Florida
Default

Lower your running airflow to 8.6. Part-throttle Lterms means above idle. If you're getting surging at idle you need to modify the RAF, as I mentioned, possibly the ve (out of curiousity, what are your Lterms and IAC's at idle a/c off?), and/or possibly the timing table(s) (as in pull/decrease timing). Drill the throttle body if you like, but my car runs like stock; a friend's car with same exhaust as mine, forged-stock bottom end, Stage 3 LS6's and a MUCH bigger cam than mine with 11.5:1 CR runs even better than my car does (My TB is going bad). If you drill your TB blade breather hole too much you will increase surging and will be forced to buy a new TB. I agree with P Mack about 35 IAC counts at idle a/c off.
Reply
Old Oct 6, 2004 | 07:02 PM
  #22  
luv2spd's Avatar
Thread Starter
TECH Fanatic
iTrader: (1)
 
Joined: Feb 2004
Posts: 1,152
Likes: 0
From: Newton, KS
Default

Originally Posted by The Dragon
Lower your running airflow to 8.6. Part-throttle Lterms means above idle. If you're getting surging at idle you need to modify the RAF, as I mentioned, possibly the ve (out of curiousity, what are your Lterms and IAC's at idle a/c off?), and/or possibly the timing table(s) (as in pull/decrease timing). Drill the throttle body if you like, but my car runs like stock; a friend's car with same exhaust as mine, forged-stock bottom end, Stage 3 LS6's and a MUCH bigger cam than mine with 11.5:1 CR runs even better than my car does (My TB is going bad). If you drill your TB blade breather hole too much you will increase surging and will be forced to buy a new TB. I agree with P Mack about 35 IAC counts at idle a/c off.
Hey thanks for all the suggestions. I'll be going home this weekend (college student) so i'll log some more and let you know what i find. I plan on opening the tb with the set screw, not by drilling. I do know that my ltrims were +8-10 at idle and the rest weren't quite as positive, but I forgot to log the iac counts when it was warmed up. I'll let ya know what I find. Again thanks for the help guys!!
Reply
Old Oct 6, 2004 | 10:44 PM
  #23  
luv2spd's Avatar
Thread Starter
TECH Fanatic
iTrader: (1)
 
Joined: Feb 2004
Posts: 1,152
Likes: 0
From: Newton, KS
Default

Ok, I found a log file that I forgot I had. It showed that at a hot idle, ac off, my iac counts were 110-115. It also showed desired airflow was 9.3. My stft were looking good at idle, about -4 to 0 although the ltfts still showed like +9 or so. It idles nice but my problems are cold start surging, and bad bucking under like 1200 or so. Hot starts aren't bad, but it still surges a little.
Reply
Old Oct 7, 2004 | 08:03 AM
  #24  
WS6snake-eater's Avatar
TECH Fanatic
 
Joined: Mar 2003
Posts: 1,839
Likes: 0
From: La Porte, TX
Default

Are those IAC counts in park? You need to look at what they are in park, not in gear.
Reply
Old Oct 7, 2004 | 09:50 AM
  #25  
luv2spd's Avatar
Thread Starter
TECH Fanatic
iTrader: (1)
 
Joined: Feb 2004
Posts: 1,152
Likes: 0
From: Newton, KS
Default

Well, I have an M6 and that was in neutral with an idle speed of about 875.
Reply
Old Oct 7, 2004 | 09:58 AM
  #26  
WS6snake-eater's Avatar
TECH Fanatic
 
Joined: Mar 2003
Posts: 1,839
Likes: 0
From: La Porte, TX
Default

Ok then...get them down and that will fix your problem.
Reply




All times are GMT -5. The time now is 07:11 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE