Tightening up the valve lash to .014 Int, .015 exhaust made a marked difference in smoothness, but not neccessarily butt dyno improvement.

Dema gives this quixotic response to your questions...


Hello, There are compressions that the engine sees. 1. measuredchamber cc + swept volumn in cc divided by the camber cc= Static comp 2. Effective comp when the int valve closes. High V.E. about 7-1 ratio and 9-1 with about 60% V.E. or alky fuel with aluminum head. #3. Dynamic comp is when the engine is running at max TQ and that is when the V.E. is increased. ....Most companies advertise seat duration at the cam and lifter interface. Only a few will give duration at the VALVE due to rocker ratios and valve lash differences.....A lot of my engine builder customers will check the intake centerline when installed or check at .050" tappet lift fo the cam duraton @.050" and the int lobe centerline.....That is when the cam is adjusted depending on comp and int closng point......When the cam design has easy clearance ramps that allows you to adjust the int closing point.....Dema Elgin

I'M NOT GETTING IT....