Re: Replacing a '49 288" with a '53 327" 4-bbl - any problems

Posted by Mike On 2011/6/25 9:29:19

I ALMOST FORGOT! The temp sensor in the head of the 50 is bigger than the one in the 50+, and the senders work differently so they're not interchangeable.

When you have the motor in, you can't get at it to re-thread the sending hole. If you make it bigger you can always use a reducer bushing to put a 51+ sender back in if you move the motor to a newer car, but if you don't drill and tap it, you can't use the 50 sender unless you rig up a brass T setup like i did, which causes the gauge to read a little bit lower than actual temp until the car is FULLY warmed up, like after a decent drive. Also, that setup is very close to the throttle linkage so you have to be precise.

MUCH better to just drill and tap the hole while the newer motor is out. It's pipe thread so you'll need a special tap. That was probably the most annoying thing i cam across in transplanting the motor, can't believe i almost forgot it.