Ashkan,

The manifold is a great thing. You can get some pretty good results by taking the stock manifold apart and matching the runners up and opening up the size a little. There was some mis-matching between the manifold and the cylinder heads and some pretty badly formed stock turns in the manifold runners. When you clean these up and disconnect the longer runners you will find that the engine in the C43 or 55 motor will run much better on top and lose only the slightest Hp below 3000 rpm.

also by removing all the screens on the MAF you will also see some increase in Hp.

Also with the manifold changes, headers, and ram air I was able to get a traction limited 13.2 sec 1/4 mile and a trap speed of 109.5 mph. So I am pretty sure the combo is working pretty well.

Jeff