Stumble off idle -

[decooney]

Originally Posted by Grubby

Duane,
I have the jets in but the weather is not cooperating. I will update all on what it takes to get the drivablility spot on. After driving with the vacuum gage it became obvious the 65 PV is likely correct. Lean conditions occur when the vacuum is higher than 10 inches. It is possible a 75 PV may even work better, but let's see what the jetting does first. I am thinking about idle feed restrictors as well. I am working through one piece at a time. John

I re-read your post and realized that you said, "occurs during light to moderate load" while above 10psi. As a first step, I would be trying the same as you are, going up 2 jets and to a 6.5pv. Its a good first test if anything, even if you had to go up 2 more primary jets just as another quick test before doing anything else. Your comment about how it occurs at "light" load is a key word. My buddies new QFT had the exact same issue. On his, after we did the sniffer test with the tuner we stopped there at bumping primary jetting and PV and started playing with IFRs (up) and (down) on PVR restrictors again. QFT thought we had larger IFRs in the carb until we measured it; nope - down 2. We had to reconfirm it twice with them, and that was it. Hope yours is solved with these primary circuit jet changes alone. Happy testing. It will be worth it once its dialed in. Can't wait to hear the final test report. Good Luck.