318 Carb Size Question

Gents

I have a stock bottom end 318 with stock cam. I have .040 decked 1.88 "J" heads with an Eddy four barrel performer manifold. I'm running Hooker headers and full dual exhaust with electric MP ignition kit. I currently have an Eddy 500 CFM carb. Seems to peter out around 5,000 RPM. I'm thinking it needs a bigger carb?



I found a deal on a 650 CFM but didn't know if that would be too big? The 650 has vacuum secondaries but wanted to get some opinions.

Thanks guys

650 would be fine. It's petering out because of the stock cam.