So I got a 81 Datsun 720 2wd z22 for free. I put a new cap an rotor in it, cleaned the carb, put fresh gas in etc.... It fired up, ran really good, then went to drive an it spit an sputter. So I figure have factory cat figure it was plugged up cut of so it was straight pipe still did the same thing but than it ran like sh*t, so I just adjusted the timing. Didn't do nothing check to see if the wire were in the right place. It sounds like the timing is off or something, an it's firing right. It's getting good spark, just the motor shakes an give it gas just shakes even worse. I don't know to much about these motors or anything about Datsun more a Toyota person, ha!

Well let me be the first to tell you. Nice score! How long has the truck been sitting? Bad gas is a possibility maybe a bad fuel filter as well. Also check for vacuum leaks. Have you checked spark and injectors?