I am replacing all rubber on the car. It runs great, but at mid RPM if I get the four barrels to open the motor boges down. Is there a high end carb setting or do I have another problem?

Could be a rich mixture, or your choke might not be opening completely. I'd start with some carb cleaner, and make sure that there isn't some gunk getting in the way. :)

bill.

Is your aircleaner filter in go shape?
As bill said I would check the air and mixture settings on your carb.
If it's a holly there should be one screw on each side of the front housing.
You need to get the engine warm and then turn one screw at a time clockwise until the engine starts to stumble. Then turn the sccrew back until the engine starts to smooth out, then do the same to the other side.
Also, spray some gunk carb cleaner in the carb while the engine is running.
Good luck!

Had the same problem with the rochester carb. re-built it and it took care of the problem

Thanks guys!!

Have the day off today will try fixing it.

Engine 350/350
42,234 miles
Qjet Carb
All numbers matching
second owner

Once you've adjusted the carb, check and fine tune your timing,(and points), then re-adjust your carb. I adjust the points with car running, this takes practice and a good ear.