Disappointing dyno results

jawbone said

Thanks for the detailed and informative response. I did cc the heads and calculate compression ratio. cc=65.6 CR=9.687:1 This was based off graduated cylinder.
Engine builder said the same regarding intake valve timing. What I do not understand is why stock Mopar 340 intake is at -2 BTDC (@.050), Are you using the advertised value of 26. May be more mis-information.
Do you know what effect leaning A/F ratio will have on numbers.

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You have to cc the cylinder with piston at TDC and add that to the combustion chamber area to get accurate CR.

When you have your cam set at 106 ICL, intake open point is measured at.006 for a mopar cam. Forget about what it is at.05. That is a measure of how fast the valve ramps up on the cam.

Jet your carb main jet so you have A/F slightly lean at cruising rpm. It should be slightly rich at WOT to make the most horsepower. I don’t know how to do that with a carter avs. You are too rich through out your power curve. Did the dyno operator change main jets and the metering rods?

What brand cam are you running and exactly how much horsepower are you looking to make?