Classic/Antique Car Repair: 67 Camaro, fuel pressure gage, electric fuel pump

Question
I recently did a complete renovation of an RS/SS with a 350 engine. Included in the renovation was a total engine overhaul. I had the heads completely rebuilt and the block reconditioned and bored .030 over due to cylinder wear. The only thing not replaced on the engine was the crank shaft, which was well within tolerance. After the rebuild and installation, I ran the engine for a couple hours, rechecked timing, re-torqued the head and manifold etc.I completed rest of the restoration and am now ready to drive and show the car. Here's my problem. When I first start the engine it runs fine for about 5 to 7 minutes. After the engine heats up, I begin to get blue/white smoke, the engine begins to run rough and will eventually die. When this happens there is gasoline puddled on the intake, the plugs are wet with gas (I've pulled them several times when this happens with the same results) and the engine won't restart until it cools and the excess gas dissipates. I've checked compression which is consistently between 170 and 180 on all cylinders. I changed the carburetor (the original Rochester was rebuilt)to a rebuilt Holley.(both carburetors gave me the same results). Vacuum is steady at about 15 in. at Idle and I don't get any gross fluctuations when RPMS are increased. I've re-checked timing numerous times, I can't find any vacuum leaks and cannot find anything that makes me believe there is any exhaust obstructions. Any help you can give to point me in the right direction will be appreciated.

Answer
Do you have an electric fuel pump on the car? It sounds like the carburetor is flooding over and it could be caused by fuel pressure too high. An after market electric fuel pump could be the problem. I would use a fuel pressure gage on the fuel line going into the carburetor. The fuel pressure should be between 5 and 6 1/2 pounds per square inch as measured with the engine running or cranking. If it is higher it will cause the problem that you have. If the pressure is within that range then the problem appears to be in the needle and seat or a sinking float in the carburetor.
Brad