High Compression 390

ICA is Intake Closing Angle.... the crank angle after BDC when the valve is closed 'enough' so that no more pressure can escape and the charge can be compressed. ICL is what you are thinking of with the 106.

I assume you want to open up the standard 63 cc Edelbrocks a couple of cc's to get to 65 cc? I'd just do some light cleanup work around the sides by the valve pockets and smoothing things out...which will help prevent detonation... 2 cc's will come out very quickly. (Try taking out 8 cc's (like I did once); that is a lot more serious work.)

Buuut....I'd go for 1 step bigger cam myself.

2.8 mph in the granny gear at idle would be perfect for moving cows around LOL