Thread: New to sbc looking for knowledge

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So as the title says I'm new to small blocks. I've learned a little and have built my first one but not sure what I've built. I picked up a 307 from a 73 nova that came with a edelbrock performer manifold and 1406 carb. Tore it down and found it was rebuilt at some point. Had rods and mains changed with bearings stamped 1994. Flat pistons and rings as well. Sent the heads out to get work done and was told they're 350 heads that were cooked pretty good. They decked them three thousands, seals and springs for a small lunati cam I had for it. Used a oreilly gasket kit.

This engine is shoved into a 85 toyota pickup 4x4 offroad toy I've built. Runs good and spins the tires easy but feels slightly gutless. I'm wondering if it's my compression ratio with 350 heads on the 307. From what I have found the 307 Is a 283 with 327 crank but I can't find what heads it came with. I've tried using the Web ratio calculators and it come out with 8.3:1 if I'm entering it correctly. 3.875 bore, 3.25 stroke, 76 mm chamers, 4.100 head gasket bore, .03 head gasket thickness?, .015 piston deck height?, flat top pistons.

I would really appreciate any insight on this. I have a lot to learn and hope to do so

Tim

307's were considered grocery-getter engines when they first came out. You can make some good torque for a small engine but those 76cc chambers are a problem. If I remember correctly, the 307's came originally with 64cc combustion chambers which would make the compression ratio over 9:1. That would help give it some guts because with low compression and a cam with overlap, that engine is probably not making good power over 3000 rpm. My advice would be to run it and save your money for the future build of a 350 or 383.