Thanks for the information, very helpful. The engine has front solid mounts. The car once ran in the upper 12's with another 350, with .040 over bored flat tops, an open hi rise, a double pumper, crane 500 x 500 lift solid cam and Holley blue electric fuel pump. Back on those days, use to be a daily driver (90's, when the gas price was low). Now with the new advantages, like internet and "lesson learned experience", I did this new engine with less, and honestly, the car feels like close enough to the way it was, more enjoyable, less hi temps and a much better gas mileage. Now, the intake is a performer low rise, but divider slightly cut in the middle (providing low torke and some upper to), the new cam is hydraulic with 280 advertise, .460 x .460 but cause' I'm using 1.6 rollers, it's around the .480 x .480. Still having the early 186 casting from the previous engine, 2.02 x 1.60 valves, massive porting job on intake and exhaust, only springs changed to the actual cam. Thin metal head gasket. Re curved Hei electronic ignition with advance springs. Now the vacuum is connected to open manifold source. Still using early msd 6 module. The holley rear vacuum became an advantage over the double pumper. Top grinder and ported around venturi edges. When I press the pedal to the floor, it opens full primaries and the engine accelerates real clean, then secondaries opens and you fill it wonderful without starving or hesitation. Rear tires: Mickey Thompson 15'x 28"x12.5" street sportsman mounted on early Graggar Tricks rims. I spent more than 3 years collecting freebies, having donors from other retire folks with leftovers. We estimate is around 10:2.1 or close to 10:5 compression, but it withstand 93 pump gas. The lower torke is impressive. If I will now this back on the 90's, I would't spend so much money.
Once again, Thanks for your advice, you make up my mind, I will save money and get a pair of CC13 Headers.
Happy new year. Blessings for you and your family.