I'm new to these groups but I've been reading the various posts for a while. I bought a 70 SS last month. The car is in great shape and is a true SS body. However, the previous owner replaced the original 396/4 speed manual with a 307/350TH automatic. He said the original motor was shot. It has a Quadrajet 4bbl with headers and actually has quite a bit of pep; especially with the 12 bolt posi rear end. I guess what bothers me is trying to decide if I should go to the expense of finding and re-installing a big block, or settle for what I have. The car has antique license plates and is only driven occasionaly and to shows.