Need some help...I think

[G.R.]

I moved from sea level(Bainbridge Island, WA) to northern CO. My car ran great after finally getting the Webers tuned and synched in WA. After moving here I have rejetted etc. for hi-altitude....but....I can not get rid of the 2,000 to 2,500 rpm or so "popping" thru the exhaust at acceration at low idle cruising speeds between 25-35mph, when I punch it it clears up and runs great as well as running great at highway speeds.

I'm at 36* all in on my timing, I've checked float levels, jets, tubes, linkage synch, exhaust leaks, etc. . I'm at a loss now as what to do. The car runs great it's just rather embarassing to drive at low speeds.

Any ideas on what to further check?

[zimmy]

Sounds like your idle circuit is lean.

[G.R.]

So what is your suggestion for checking or correcting this? jets, tubes?timing?

[68gt500]

Yes, it sounds like you are running a touch lean on the idle circuit.

First thing I would try is opening up the idle mixture screws, an aditional 1/4 - 1/2 turn.

If you feel an improvement, then I´ll go a step richer on the idle jet, or decrease the idle jet holder size.