Hesitation at low rpms...

[kmcbride74]

All,

BACKGROUND: Wrapping up my 305->350 swap, in fine tuning mode.  Truck runs well for the most part, idles well, nice power from about 1/4 throttle all the way to the floor, have timing set per cam spec., 12 degress btdc, valves adjusted. 

SYMPTOM: When taking off from a stop, when I first press the gas, it hesitates for 1-2 seconds.  Immediately after that point it runs strong, no missing, no hesitation.

Would this indicate that I need to retard the timing a hair or advance it?

Or, do you have suspicions of anything else that might be the culprit?

Thanks in advance!

[topp]

305 or 350 (no need to mention what it was)?
tbi or carb?


Hesitation off idle is usually fuel/air related...

[kmcbride74]

Its a 350 with carb, Edelbrock 1406, brand new, supposedly not needing any adjustment...

[Captkaos]

Don't assume that it is setup perfect right out of the box.  You will need to preform some kind of adjustment.

[jaredts]

What's your idle speed?  You could experiment with the different holes on the accellerator pump to see if that helps.

[kmcbride74]

at operating temp right at about 700 rpm...I dont think it's an idle adjustment issue.

[topp]

at operating temp right at about 700 rpm...I dont think it's an idle adjustment issue.

Auto or stick?
Auto should be 700-750 in drive, stick about 550-600...

It sounds more like a jet issue....

[ohio hab]

Need to advance the timing , 2 degrees is a good starting point, or needs the accelerator pump adjusted , or bigger squirter. Also carb could be lean. Iam not familar with Edelbrock carb's, I alway's run Holley's, but your symptom's, apply to any carb.