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Demon Carbs

Hello all, thanks for your time. I have a 1968 mustang with a newly re-bult 302. The heads were mildly ported and fitted wiht oversized valves, and It has a comp cams cam with .456" lift and ~260 degrees duration (i think) set to about 16 degrees advanced (cam manufacturers recommendation) and a 625cfm road demon jr. The carb's butterflies are set according to the manual, along with float levels. The engine surges a little bit at idle, and when shifted into gear (auto tranny) it either dies or will die soon, or bogs and dies when I try to acclerate. I think it has something to do wiht the idle mixture, becasue the manual doesnt explain well how to set it, and I'm not good at telling whether it is rich or lean. the idle is set at about 650 rpms. Any help, tips, or ideas would be greatly appriciated.

Thanks!!!

Reply to
bobar3425
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Reply to
<HLS

There idle is one thing about a carburetor. In those years, you screwed in until the car started to miss. Then opened until it ran smooth. Go back and forth between both sides until it is optimum. There is a more precise way with propane gas, but you can get the IDLE close enough this way.

That doesnt mean the jetting is correct. Two separate concepts.

Idle adjustment does not have the impact that some think it has. Still it must be adjusted properly for a relatively smooth idle.

If you have mileage or acceleration issues, look elsewhere.

Reply to
<HLS

Your gonna need a manual tranny or modify your automatic tranny ie stall converter with atleast 2500+ Stall!!

Reply to
Daryl Bryant

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