I'm running a Edelbrock Thunder 800 on my 408. All I had to do was set the idle and idle mixture. I paid $100 for a tuning kit with jets and rods. When we ran it on the chassis dyno the AFR was right where it needed to be so I sent the kit back! I have no complaints with the carb at all.
Edelbrock Thunder Series AVS Carburetors 1812
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