Thread: Can I get 9:1 static compression

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I just pulled a 402 apart and found 4.125(std bore) very little wear( no ridge) on cylinders. Factory cast pistons. Cast crank is perfect on all journals. I don't know the history of this engine other than that the odometer on the car is 95,000 miles. I can't tell if the bearings are original or not but the crank looks as if it had just been reground. I will have to mike it out. It did have fel pro gaskets and a comp 268 cam. The engine sounded great and ran even better...I know what you're thinking, why did he pull it apart??? I would like to know if I can get 9 to 1 out of this factory 8.5 to 1. The heads are 292 casting 2.06/1.72. I cc'd and got 113cc on all chambers. The piston at tdc is very close to deck but I will have to measure depth with dial. I would guess that it is less than .010. My plan is to use the cast pistons and hone the cylinders. I'm spending the money on a hyd roller cam(224/230 .510/.510) and heads. I will pocket port and new stainless valves with associated 3 angle job but not a whole lot more than that. I'm trying to keep it at budget as the wife already says I spend too much on hunting. I'm trying to avoid boring. I've heard that you can deck the heads about .030 without too many issues. This is the 3rd 402 that I have done but the first one I have tried to do on a budget. Thanks for any help.

cut the hell out of the heads try to find some new old stock small bore tin GM head gaskets should get there you should only need about 5 cc to get 9to1 or very close so it should not take much but i would still try to find a small bore head gasket

summit sells .018 head gaskets for the std 402. I'll give it a shot. Thanks Pat