Two and a half days on the dyno. What a shit show. I could write two pages but I'm gonna give the really condensed version. Started with my new intake. Engine kept breaking up. It was random where during the pull it would. One pull up 50 hp and the next lose it with zero changes. New plugs same shit. Up and down with fuel and timing. Next day different plug wires, cap, and rotor. Nope, not it. Plugs looked good. We were beginning to think the intake was the problem. Changed the magnetic pick up in the distributor. Not it. Checked valves, not it. Added one inch spacers to move the carbs further from the runners. It picked up 30 hp at 5400 so it liked that very much but still breaking up. It would show up in the vacuum readings also. Fuel curve looked good. Now we figured it must be the intake. Put the edelbrock back on. Nope! Still breaking up. At least it wasn't the new intake. Changed coils. Nope! Put a different engine on the dyno and zero problems. A very experienced dyno operator, another person who did cylinder head development for Hendricks for twelve years among others and everyone is stumped. So where it left off is 663 hp with the engine breaking up. It made 40 more hp than the edelbrock. I can't afford to go back to the dyno so it's back in the garage for me to figure out. It should make 700 all day with out breaking a sweat. Hell, the car went 10 teens with the edelbrock intake and this one show it is capable of at least 40 more hp minimum.