I have a 66 mustang coupe, I6 conversion to 302 V-8. It has an Edelbrock 650 cfm 4 bbl, Edelbrock Performer dual plane intake, HEI ignition, Gt40 heads with headers. The transmission is the C-4 auto. The engine runs fine when first started and does so until water temp reaches around 200 deg. Then the engine bogs down whenever I try to accelerate and runs very poorly (generally dying at stops unless I shift into neutral) at idle with or without a/c on. I've changed fuel lines to 3/8 aluminum tubing running them in the V-8 stock location and double checked to avoid all heat sources. I've readjusted the carb jets, and rechecked the timing. But, like I said, it runs perfectly when cold or cool. I'm at a loss to what to do next. HELP????