Stumble off idle -

[blykins]

Originally Posted by Grubby

The Holley 750 ran really well at steady cruise and part throttle. That indicates to me this is a set up issue with the Quickfuel.

The car is no fun to drive with the Quickfuel. It was much more pleasurable with the Holley and my wallet was fatter.

I will try a few more things and then throw in the towel. It is foolishness to keep spending $25 a whack to try air bleeds or jets. I can only think of one other thing to try anyway - go up in the IAB size.

Idle was mostly set without touching curb idle screw. I went up about 1/4 turn. I am sure the transition slots are still good. The four idle mixture screws are out about 1.5 turns.

John

At any time, I will buy the carb back from you, how's that? Like Patrick said, I know it's frustrating not having any time to work on it.

Did you get a hold of Scott?

[decooney]

John,
Sounds like you are done with it, but I only had one last thought - back to my original question when you started with the new carb. In any of your conversations with Phil at Quickfuel did he ever recommend increasing the size of the idle feed restrictor jets for the transition circuit? I realize you bought an HR series carb vs. a Q series version but don't know if the HR has the adjustable metering blocks or not since I don't mess with the HR versions carbs. The only reason I ask at this point is purely for reference and notes.

Note: this was the fix on my buddies QFT carb after working through it with QFT techs. Changing primary/secondary jets, acc pump cams, air bleeds, power valves, all had nothing to do with getting his setup to run clean below 2500 rpms at cruising speeds. It was those darn idle feed restrictors that allowed more fuel at slow cruising speeds and resolved the "stumble off idle" issue which is your original post for this thread. Its a bummer you did not get a chance to try the Q series carb.