Hello Nick
You could bench start the motors. ( start them out of the car) It's a bit of mucking around but not as much as pulling out a motor then fitting another only to find out the new motor is stuffed. You will need a gearbox and starter. It's ok to run them for a few minutes without a radiator just block the bottom radiator hose and fill the block with water. Don't let it get to hot
. If you want to run it for more than two minutes jamb a running hose into the bottom radiator hose . Also a slap up exhaust will be on the cards if you want to listen to the donk and don't want to upset the neighbors or the missus.
A mate of mine used to start / check motors with no cooling and no exhaust. He would fill the carby with fuel and if it started hold the throttle full open , if it didn't hand grenade he figured it was ok
Brad.
Ps if you do this , tie the motor to something solid on the distributor side so it won't bugger off down the paddock when you rev it.
