Maybe trans????
OK--- b4 you guys made it more reliable the car would run down the road at 80mph--- now that you've worked on it it chugs at 55mph!!
"It's a 225 slant six, and me and my dad just replaced some stuff on the engine to try to make it more reliable, we also rebuilt the carb. And another wierd thing is that when you unplug the vacuum Hose for the advance at the carb it doesn't bog down or die so that's really wierd"
you need to not make more problems by diagnosing something else-- something you guys did has caused this problem-- go back & check out your carb work-- did you hook up the kick down rod to the tranny?
Are you running points? Lawrence