low speed surging
Thread Starter
Race Director
Joined: Sep 2005
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From: Farragut,TN
low speed surging
We have a 25 mph speed limit in our subdivision at that speed first gear car surges. is it because of lean condition or timing?
Last edited by 694speed350; Apr 4, 2016 at 06:30 PM.
Race Director
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From: PARADISE
St. Jude Donor '09-'11-'12-'13-'14
Timing more than likely.
What are all your timing numbers?
Is the engine stock or modified?
At 25 mph in first, what rpm is it running at?
Remember Lars famous line, "most carb problems are really timing problems"
What are all your timing numbers?
Is the engine stock or modified?
At 25 mph in first, what rpm is it running at?
Remember Lars famous line, "most carb problems are really timing problems"
Last edited by claysmoker; Apr 4, 2016 at 09:38 PM.
Melting Slicks
Joined: Apr 2005
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Set your timing back in small increments until the surge is gone.
Is your vacuum advance can connected to full vacuum or ported vacuum?
Your vacuum advance can may be coming into fast, thus causing the timing to be too far advanced.
Is your vacuum advance can connected to full vacuum or ported vacuum?
Your vacuum advance can may be coming into fast, thus causing the timing to be too far advanced.
Burning Brakes
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From: Austin TX
Le Mans Master
Joined: Jul 2006
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From: charlotte north carolina
As posted above, it may be excessive vacuum advance timing causing "trailer hitching". Simple test is to disconnect the vacuum advance can and test the car. If that solves the problem, install an advance limiter as Lars sells.
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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The edelbrock you tube vid says it can be from the carb tuning or dirty carb as well. You can look up your carb info and google vids for trouble shooting. Good luck
7th Gear
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Race Director
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From: California
OP... this is almost always a fine tuning problem with ..A/F and timing...I am working on the same issue now... it could also be a vacuum leak or other problem like that, but if everything is in check.. then it is just fine tuning as i stated,,,,
Last edited by pauldana; Apr 7, 2016 at 11:08 AM.
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
A low speed or cruising surge is usually caused by lean condition, fatten up the carb and see if it goes away
Thread Starter
Race Director
Joined: Sep 2005
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From: Farragut,TN
I usually do but coast this is still in 1st gear. my mechanical tach dosen't work why would you want to run in 2 or 3rd gear alough it will take off from a standing start in 3rd. however it shouldn't surge in first gear at 25 mph. just don't like the surge at low rpm.
Thread Starter
Race Director
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From: Farragut,TN
Team Owner
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St. Jude Donor '05
