If you drop the compression, you'll need to down size the cam even farther. You'll be fine with 10.3 and 91 octane with those the small bore cylinders and a 0.040ish quench. Small bore and tight quench really fight off detonation. Its the quench that matters, head gasket thickness lets you play with or plan for the quench.
I want to keep the compression. I like the sound and performance of that much squeeze. what's the optimal cam spec for that much CR?
Define your idea of "optimal" first. Personally my optimal is the highest average power across the entire RPM range. That leaves some HP on the table but only at the peak in high RPM range, interesting that chasing the highest peaks reduces the overall highest average quite a bit because there's a huge reduction in bottom end power. My version wouldn't be great for every situation. I'm running a comp 262 in a 307 with same 305 heads. Same bore as your 283 1/4" more stroke. My compression measured at 10.4:1 I love that little misfit
That will drop it about a half a point but might get it out of detonation range. 194 is the biggest valve you can use with a 283. Those heads work good. Had a set on the first 283 I had in my 38 chevy coupe when I bought it in '74 It had a L79 cam in it with a borgwarner 4 spd and a mr gasket vertical gate shifter. Super fun car to drive when I was young. Now its got a 409 and a switch pitch TH400 and its just as much fun and a lot LOUDER!
I don't think you will get an experienced hot rodder to tell you this is a hot deal, but like the one guy said ,its your turn and you'll need to do it once anyway. I guess my advice is if you can afford to buy it without breaking the bank, go for it and let us know how it turns out. Beware of changing the cam very much you may end up changing valve springs also.
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