Sister had a later 412. It managed to swallow the #3 exhaust valve (like a lot of them did). I swapped in a 914 motor. Not a big jump in power, but it helped. While later she was having some tranmission troubles so she took it in to a shop. They proceded to pull the automatic and disassemble the transmission (without her permission) and then tell her she needed a mega $ rebuild. She told them to pound salt, she was junking the car and they should put the transmission back in the car before she picked it up. They put it in the back seat. I pulled the engine and put it in my '75 camper bus. Only regret was not grabbibg the gas fired heater off the 412. Rest of the car was pretty much junk. My own opinion: No air cooled VW should ever have anything but a full manual transmission. Friend has a bug with auto stick shift. I think she wants to sell it.