Motor issues.

I lost about 6 inches of vacuum moving from sea level to 5k feet, went from 17 to 11 inches and it bounces a bit there too. Add a lot of cam and you are going to lose even more. Not familiar with the Edelbrock metering rod setup.. can you install a different spring? Pull the plugs and see what they look like. Getting my single vacuum secondary carburetor tuned in properly here took quite a few days.

No idea how your header tubes can be that cool.