Is the Ralley 350 radiator a 4 core like the W31?

 

I looked in a book I have and heavy duty cooling was an available option for the Ralley 350. It also appears to have been standard with a 3:42 or 3:91 axle ratio but not available with an M21 4 speed. If you need a 4 row, let me know as I have an extra one that needs to be recored. I'm also in Maryland and I found a shop in PA that recores and restores the radiators for Thorntons and other restoration shops. They even straighten the tanks so there are no dents.
Brian

 

I don't have my reference material in front of me, but I'm pretty sure that neither the Rallye 350 package nor the W-31 package automatically gave you a heavier duty radiator. Rather, the radiator was purely a function of which rear gears you got. (Of course, A/C also forced the 4-core radiator.)

Now, since a W-31 had steeper gears as standard, that may have forced a heavier duty radiator. Likewise, when you ordered an M21 4-speed, that automatically gave you steeper gears, which automatically gave you a heavier duty radiator, which is why they wouldn't let you order a heavier duty radiator along with an M21. They created the order sheets to make sure you weren't charged twice for something.

All of this information can be found in the assembly manual, though you have to look at several different pages in several different sections and connect the dots.