big block carb size

Holley or Edelbrock? Either. Some people like one some like the other. Personally I like Holley because of the number models available and they just plain work awesome.
On the other hand, I just put a Thunder series 650 AVS on the engine i built for a friends 69 383S Barracuda and took it for a ride. Let me tell you that is an awesome street carb. Right out of the box,stock A-body big block exhaust manifolds, bowl ported heads, Comp Cams extreme energy cam. KB pistons. 4-speed. Runs flawless. Very responsive. May have to have one for my street car. I wish they had it a 750 though.