It’s Time For A Cooling System Update On Your Class Truck

By Steve Stillwell
Truckin’ – February, 1988, Volume 14, No. 2

It has become commonplace to swap late model V-8s into the engine compartments of older trucks. After all, we are all interested in creased performance as well as additional reliability. It’s a great idea and often times more economical to go this route, however, some problems do develop with this mixing of old and new components – the biggest problem commonly being engine cooling! The original radiator wasn’t designed to meet the cooling needs of a late model engine. Now, before you get all defensive about the original top flow radiator, I would like to point out that in their day, they were efficient for the most part. However, the V-cell design greatly restricts the flow of coolant, and also makes them almost impossible to clean, using a method commonly referred to as rodding-out. On the other hand, a late model truck or car radiator is called a tube and fin core, which refers to the design of the cooling fins and rectangular shaped tubes through which the coolant passes. As Jack Mattson, Jr. of Continental [*Now Mattson’s] Radiator states, “The most important element of cooling isn’t the capacity of the radiator, it’s the amount of tube-to-fin surface,” which leads us to the larger, more efficient, CL or T-Cell radiator, commonly called a cross flow. This translates into two distinct advantages to using the crow flow over the older styled radiator; not only does the coolant pass through the newer style radiator, but so does the air which dissipates the engine’s heat.

The design of the old style radiator is also a major problem.The tanks, more specifically the top tank actually sits atop the radiator core, being joined by a rather weak solder seam. For this reason, the operating pressure is limited to a maximum of seven p.s.i. or less. (The late model radiator operates at 12 to 15 p.s.i.). What this means is that the lower pressure allows coolant to escape when the temperature rises, especially when the engine is turned off, and the coolant temperature rises to 225 degrees or more! Suddenly, you are faced with a boil-over. Unfortunately, installing a higher pressure rated cap will do more harm than good, often leading to complete radiator failure.

So, not only can the T-cell radiator do a better job of dissipating heat, but can also handle the higher pressures associated with higher engine temperatures, without losing coolant, when used in conjunction with a recovery tank.

On the building of the old Truck Rod, I opted to change the whole set-up. After all, I didn’t want a $10 radiator in front of a $5000 engine, so a change was in the making. Matter of face, Jeff Perkins and I teamed up and decided to rework the radiator mounts on the truck to accept a large four-core radiator, like the type used in the 427 cubic inch Camaro, after all, there is a 383 cubic inch, blown small block Chevy powering the Truck Rod. This meant having a radiator fabricated, which lead us to an area specialist, Continental Radiator, 10511 Beach Boulevard, Dept TR, Stanton, Calif. 90680. As you will see from the following photos sequence, Jack has some good ideas to follow, when it comes to the fabrication of a cool radiator for a hot truck.

*All images are of Jack Mattson and his work and are copyright Trukin' magazine © 1988.