Demolition Derby Radiator Guide
One of the most important pieces in a derby car is the radiator. The key to this sport is: be the last car running. Having your engine not overheat is a critical key to success. The radiator is probably the most vulnerable item in a demolition derby car. Many people believe that derby drivers only go backward, but the sport has evolved over the years. We hit with our front ends, as much if not more, than in the old days. Derbiers still hit with the rear ends, but it’s not like it used to be. I use a Small Block Chevy engine so the radiators I run will have the Chevy pattern, which has the neck on the upper driver side and the other neck is on the lower passenger side.
Speedway Motors offers a variety of widths in their radiators. The nice thing is these radiators are high quality and do not contain any epoxy. They utilize two 1-inch wide tubes that hold the same capacity as a four-core radiator. These radiators are also priced well and won’t break the bank. Speedway also offers radiators for Ford/Mopar and Chevy applications.
These radiators are measured outside of the tank to outside of the tank. A quick measurement will allow you to determine what width of radiator you will want to purchase. Personally I choose a 31” Wide Radiator when I run 1971-1976 Gm full-size cars. I also run this width in 1979-2002 Ford cars, but there is not as much room to each side of the core support. I like to have room on each side of the radiator because the car is going to get smashed. The more room you have around the radiator the less of a chance the radiator will get ruined. There is still a chance that it will get smashed from the front side because there are so many things that happen in a derby. Someone’s car may be nosed or just simply sit higher. A balljoint could break which could cause the front end to drop and allow someone to clear the core support off along with the radiator.
The 28" Chevy Universal Aluminum Radiator and the 28" Ford/Mopar Universal Aluminum Radiator are the most ideal for Mopar cars and 1979-2002 Ford/Mercury cars. The core supports are narrower compared to old iron GM cars. This will give you more space on each side of the radiator. You can also run this radiator in a 2003 and newer Ford car, but I would recommend Speedway's 26" Chevy Universal Aluminum Radiator. The front frame rails on 2003 and newer Ford cars are very narrow so you will need to remember this when purchasing a radiator.
I also run a 5.3 LS engine. The water pump has the inlet and outlet on the same side. To make things easy, I purchase a double pass radiator. These radiators offer a couple of different benefits. First, I do not have to route the radiator hose to the driver’s side. I always worry about cutting the hose because I run a mechanical fan. Second, these increase the cooling capabilities since the water passes through the radiator twice before returning to the engine. I chose Speedway's Double Pass Aluminum Radiator.
Speedway also offers radiators that are as narrow as 22-inch, so depending on the width you need; we will have an option for you. The other great thing about these radiators is they are able to flex. We have had many radiators that have a twist but still hold water perfectly. The radiator in this car is twisted but still held water after I won.
I would recommend purchasing a new radiator cap. I run a Stant 28-32 lb. Radiator Cap. I only choose that high pressure cap if I know my engine has good head gaskets. Stant offers different rate caps for different applications. Stant also offers a 21-25 lb. Radiator Cap. Speedway and Afco offer different rates of caps which are also high quality radiator caps.
