Carb Adjustment?

[fuzzylloyd]

I recently purchased a cobra with a shelby aluminum block with dual 450cfm Holley carbs(550HP\500TQ). Extremely happy with everything. Recently though the car wants to stall even during mild braking. As long as I tap the gas just before I stop it idles fine. I also have noticed a slight backfire through the pipes as I shift gears during spirited driving. I am not a mechanic but it seems to me this is most likely a carb adjustment that I would like to learn how to do myself. Any advice would be much appreciated.......FUZZY

[wtm442]

1) Check the timing.
2) Replace the cap, rotor and plugs if its time for a tune up.
3) Check the float levels and make sure they are not too high.
4) Go but Dave Emanual's Holley Carb book and read it once or twice before doing any major changes to the carb.

Do NOT make any carb parts adjustments (squirters, cams, jets, power valves) until you rule out the simple stuff first.

[The Dreamer]

One of the easy things to check is to make sure you don't have a intake leak. Try tightening your intake bolts. I had some of the same symptoms, but when I tighten the intake the stalling and backfiring went away.

[Bonos]

Fuzzy,
When you do your carb adjustment make sure you have a vacumn gauge atteched so you will know when you have the hignest inches of vacumn
obtained.
Also check vacumn readings at 2700 -3000 rpm's to insure proper ajustment at higher rpm's.
The backfire you hear between shifts will come from fresh air being sucked into the exhaust system from loose bolts or blown gaskets at exhaust manifolds or collectors.

Bonos

[Zoom This]

Get your floats adjusted spot-on first. Sounds like they're set too high and flooding the motor with too much gas on braking as well as on hard acceleration (sloshing).