Hey everybody new to the website and would like to say thank you in advance for anyone who takes the time to read. My name is Brian and I recently aquired a datsun 521 for my son and me to work on as a project. When we got it the electrical was in pretty rough shape it had no spark but it would turn over. It had no lights, fan, and the carburator jets dripped instead of spraying. We now have lights the carb is clean and motor is getting gas. I also took my boy and hit pick and pull and found a distributor setup from a 1980 nissan changed a few things and got a proper coil replacement for the new distributor. I now have spark at all 4 cylinders. So i have spark and i have fuel but it will not start, instead it turns and periodicaly backfires out the exhaust pretty violintly untill killing the battery I smell fuel and i rechecked the spark and it was good. I also checked the timing ( as per other forums on this site) and at tdc I believe i am at 1 and from there its 1-3-4-2 counter clockwise. So im running low on ideas and any help would be greatly appreciated.