[Trent7276]

Hey all,

I finally got my Performer RPM manifold and Edelbrock 1411 750 cfm on. Everything runs great out of the box except coming off a full stop, the engine acts like it bogs or will die then catches quickly up. I have a 4-speed M-22. Also on some cornering it sometimes hesitates. The manual is a little foreign to me as I haven't ever tuned a carb but maybe you all can tell me some pointers?? Thanks! (400 engine, 2.5 flowmaster 40 series, stock headers, #47 heads, Malory Ignition Coil and distributor)

Trent
1968 Pontiac Firebird 400

[Trent7276]

Hey all,

I finally got my Performer RPM manifold and Edelbrock 1411 750 cfm on. Everything runs great out of the box except coming off a full stop, the engine acts like it bogs or will die then catches quickly up. I have a 4-speed M-22. Also on some cornering it sometimes hesitates. The manual is a little foreign to me as I haven't ever tuned a carb but maybe you all can tell me some pointers?? Thanks! (400 engine, 2.5 flowmaster 40 series, stock headers, #47 heads, Malory Ignition Coil and distributor)

Trent
1968 Pontiac Firebird 400

[Trent7276]

Oh, and I just got back from a test drive. If I take a really hard corner with the clutch in, it dies, both right and lefties. But with the clutch out, it lives! Hmmm....

[burch]

Kind of sounds to me like the float level is set too high. During acceleration or cornering, fuel is sloshing out of the bowl vent and causing a super-rich condition.

With the clutch engaged going around a corner the momentum of the car will keep the motor turning during this momentary condition. Do you feel a flat spot going around the corner?

[Trent7276]

sometimes a flat spot appears when rounding a gentle corner at partial throttle...just a hair off idle. If I sit at stop and rev the engine off idle you can definately feel and hear a flat, stumble right away just as I hit the accelerator down, then clearing as the engine revs higher. Its like flem when your coughing, not a crisp clean vroooom! If I keep the revs a few hundred RPM higher off idle, and then rev the engine, there is no problems at all!

[Roger C]

Add accelerator pump shot if that dont fix it up the front jet 2 sizes,but it sounds like you need to give it more pump shot,also check the float levels.
later,
Roger

[Half-Inch Stud]

...and the plugs?

do they have Black death?

Soot from rich runnig just doesn't clear up or burn off.

Suggest you look at the plugs until you find all the carbon-fouled plugs and replace em.

0.045" gap, and a trusty HEI ought to clear the throat.

H.I. Stud

[455Dave]

The Edlebrock AFB type carbs can flood in hard cornering in tight suspension cars. If the float level is good but it still dies during hard cornering, the easiest fix I've found is to get some gasket material similar to what's used on the airhorn gasket and make covers for the openings over the bowls and the 2nd accelerator pump hole and glue them in place. This worked on a vette and a 70 Formula clone both stiff suspension cars.