The car was run without an air cleaner on the dyno and run with the dyno headers. I'm running a set of HP exhaust manifolds on the car now and an unsilenced air cleaner housing.

I have switched from headers to the manifolds in the past and it lost a few tenths, so; probably killed off 20-25HP. That was with a cam that was more suited for headers, the cam I have now was spec'd for the manifolds, for what that's worth.

Ignition timing is the same as it was on the dyno.

I did fatten the carb up from what it was on the dyno because it had a lean bog when I put it in the car and floored it, we're not talking major changes, the jets are the same, just one step smaller metering rods and a little more aggressive metering rod spring to enrichen things more quickly.

Compression in all iterations of this engine has been 9.35:1. The cam is around 250@.050. FYI- both the air cleaner housing, manifolds and compression ratio have all been the same on the car in the past, when it had less power, and where it ran a best of 12.25 in similar conditions as today.