69 valiant 273 suggestions

I have a 67 cuda fastback with a 0.030 over 273. It has a Hughes cam and a 500 cfm Edelbrock carb , stock intake, iron exhaust. I had the heads angle milled to try and get the compression up. Problem is, replacement pistons are 0.50 down in the hole. The result is an 8.2:1 motor. Custom pistons are very expensive. I thought about magnum heads but the valves wont fit without griding . I ran the car one time and it went 16.62 at 84 mph. Thats with a 3;23 7.25 pegleg rear axle. and stock 904 trans. I would like to keep it in the car as it is the orignal motor, but there are few gofast parts for it. I bought a 340 block and im building that.