Lean Stumble
Thread Starter
Racer
Joined: Mar 2001
Posts: 272
Likes: 3
From: Marion Ia
Lean Stumble
What does a lean stumble feel like. I have replaced the Quadrajet with a
670 street avenger. I have read in the forum that it would be jetted extremely lean and that I should up the jet sizes. Under acceleration it seems to hesitate, it is a semi miss that is ongoing. It will clear out as I get to speed, but will show up again under part throttle acceleration. If I bring it up slower it seems fine. Been thirty years since I last tuned a holley and my memory is not what it was
670 street avenger. I have read in the forum that it would be jetted extremely lean and that I should up the jet sizes. Under acceleration it seems to hesitate, it is a semi miss that is ongoing. It will clear out as I get to speed, but will show up again under part throttle acceleration. If I bring it up slower it seems fine. Been thirty years since I last tuned a holley and my memory is not what it was
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
i put a street avenger on my old classic mustang. on the mustang forums the general consensus is to take the back jets on the street avenger and put those in the front and then replace the back jets up 2 numbers.
i did this on mine and it ran perfectly.
for chevy engines who knows though, i am still new to tuning these in.
i did this on mine and it ran perfectly.
for chevy engines who knows though, i am still new to tuning these in.
Race Director
Joined: Apr 2000
Posts: 17,672
Likes: 199
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
If it has a power valve in the primary metering block only then you need a 6-8 jet size difference between the front and back 
Also a bigger squirter will usually help an off idle stumble
Also a bigger squirter will usually help an off idle stumble
Drifting
Joined: Sep 2006
Posts: 1,986
Likes: 21
From: Columbus MN
