Sbc bogging at around 40 mph and above

have you checked your exhaust sys especially for a plugged up catalytic converter....ted

I don't have a catalytic converter. But I checked the accelerator pump and it seemed to be working right. I moved the linkage back to the middle and it helped a bunch. It will still hesitate al little but it doesn't seem like its about to die.

Good thoughts so far.....check fuel filter, fuel pressure, and the choke to make sure its coming off and not pulling back in choking the carb off.......