401 with holley truck avenger and edelbrock dual plane.
My rig is now emissions exempt. I haven't done anything to the tune in years because once it passed I didn't want to tinker with it.
But now I am messing with it. I found the power valve was leaking and replacing it took away the almost constant off idle stumble and occasionally dying.
But even after fixing the power valve, adjusting the accell pump and increasing the advance on the timing it would still occasionally hesitate off idle.
A long time back I put in 61 primary jets for one of my annual trips to Ouray and since it passed emissions with these jets, I left them in.
I swapped the 61's with 64's a week ago and since then I have had zero instances of any hesitation/stumble off idle. I shouldn't be surprised a small change like that would seem to have eliminated a problem, I am just happy it did. The jeep hasn't been this 'drivable' in a long while. And I am loving it.