Hmm. That’s quite some detective work. Leave it to Mopar to do some odd like that. I don’t know what housings either of the motors I had used but they would both go to 225 on a hot day in Texas in a heartbeat. The thermostat may have been the problem. I know my block was a NOS shortblock so I probably had a regular housing. I’ve still got the block but have not used it again.