**Milling .030 off '920 - 273 heads**

cannucky said

Okay I'll be the one to ask -Why ? You just got back on the road , adding 1/2 a point of compression isn't going to give squat performance wise , if it were me I would spend on porting the heads and a mild cam upgrade . It will never be a rocket ship so why not enjoy it as the sweet *** vert that it iz ?

Click to expand...

This is where I was trying to go. Both the "302" casting and the "920" casting are closed chambers, small valve, and probably flow close to the same. If you have already milled .030 off your 302 castings, you have already decreased the chamber volume by about 5.7 cc. 273 pistons are generally .02 in the hole, so there is good quench and good compression. If you have bored your block that tends to increase compression slightly. I would say that if you would like more power, to tune what you have. It sounds like a great little motor. What are the specs on the cam? What distributor and timing are you running? What Carb?