Thanks for the suggestions, Head bolt torque was gleaned from some well respected racer in my forgotten past. Been working trouble free for 30 years. These are not small port heads. All the above intakes are a power loss to a stock 340 intake. Power on this engine in a 4 speed 64 Barracuda is breathtaking. It took an old 11" scalloped Borg and Beck clutch to hold it. I'm not changing anything on this motor. It morphed to this incarnation over 10 years from a stock 2 barrel and everything in between. I'm just letting people know what has worked for me. There is not "one and only" perfect combination.
The 66 is now a ballanced and blueprinted Commando with a E-4 Isky cam. The next 273 for the 66 Formula S is likely to be a ballanced and blueprinted +030 273 with TRW forged 2 barrel pistons, 340 rods and 273 forged crank. I'm thinking a small Racer Brown Mechanical cam and Schubeck lifters. I have a set of 302 heads, milled block and intake sides, Port matched, blended bowls, and cc' chambers. Topped off with a Holley Street dominator single plane and 72 Thermoquad Carb. That should be interesting...