Bad knocking under feet

Hey everyone, I recently bought a 1973 dodge dart sport h code car from a yunkyard for 3k. She had been sitting for more than 20 years after the previous owner drag raced it. She has a ford 9 inch rearend that he had swapped into it, and he also swapped in a first year 360 for the 340. The engine runs amazing for the situation and does "drive." However, when we start driving around the neigherhood, there is a really bad knocking under out feet. Its definetly not coming from the engine, but maybe the torque converter and or flex plate is the problem? Somehow the tranny fluid was still in good shape after sitting so long but maybe the tranny is screwed up too. Its a 727 btw.


Also, when we press the brakes, the car wants to die. This seems vacuum related but i dont know.

Thanks, Andrew
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Did you take the vise-grips off the drive shaft? :poke: