[dayscreekranch]

49 ford V8 with isky max 1 cam, mallory dual point distributor, offenhauser 400 heads, offenhauser 2x2 manifold with ford 94 carbs with powers valves plugged and H42 jets. My problem is it has a flat spot. It idles well and runs at high rpm excellent but acts as if it is running out of fuel just above idle. At idle it has approximately 17" to 18" of vacuum.

[F-1Rodder]

Sounds like your distributor advance curve is off somehow. You need to measure your advance throughout the rpm range and compare that to the recommended curve. It sounds like you don't have enough advance at low rpms based on what you have written. If you find that the static advance is OK and the high rpm advance is OK, then you may still have a rate of advance problem which you need to solve.

[ThosLeete]

Dont plug the power valve in the primary carb its function is to enrich the fuel charge when the vac drops off (power valve) use the center carb as the primary and then run progressive linkage to the #2 carb so it acts like a passing gear---the best of both worlds power and economy.Also a word of caution you will find that if you run both carbs straight up the back cyls will over-fuel and the front ones will starve or run lean--been there done that...tom