There are times when looking at something from a different angle gives you a fresh perspective-in more ways than one. So it was while sitting on a creeper in front of our project RamRodder. We were kicking around options for a radiator when, from our low-angle position, it struck us that the grille opening was much wider than it was tall. The stock radiator was tall, had a narrow downflow design with a good deal of the core hidden behind the hood. From our vantage point it appeared as though a short, wide crossflow radiator was the way to go.
The AFCO crossflow radiator...
The AFCO crossflow radiator takes better advantage of the Plymouth's grille opening than the stock downflow design.
Thumbing through the Speedway Motors catalog we came across a variety of AFCO universal fit crossflow aluminum radiators. The one we settled on was 25-1/2 inches wide and 19 inches tall. To fit this cooler between the framerails would require some modifications, and although we could have gone with a slightly smaller unit that would have fit easily, we decided our blown Chrysler should have all the cooler we could cram in and opted for the largest available with a shroud and electric fan.
When discussing our radiator requirements with Jay Miller of AFCO, he agreed that the crossflow design had advantages for our application. He also pointed out some other facts to take into consideration when selecting a radiator. At one time the rows of tubes in a radiator was a big selling point. The theory was the more the better and three or four rows were thought to offer the optimum in cooling. However, the multiple rows of tubes (particularly when they were staggered) and a high fin count (which was also thought to be beneficial) actually impeded airflow through the core. Today it's known that fewer rows of larger tubes are more effective. The goal with both the rows of tubes and the number of fins per inch is to provide the maximum surface area with the least amount of resistance to airflow; our AFCO radiator has two rows of 1/2-inch tubes and 14 fins per inch.
AFCO radiators from Speedway...
AFCO radiators from Speedway Motors are beautifully built. They're available in direct fit and universal configurations.
While aluminum radiators work well there are some precautions that go along with their use. While this sounds out of place, always make sure the engine is properly grounded to the frame-if it isn't, the possibility exists that the electrical system will try to ground through the coolant and the resulting electrolysis will destroy the radiator in short order. Another precaution is to use the recommended pressure cap. Aluminum radiators will stand steady high pressure but sudden bursts from a percolating cooling system can cause damage-a 16-18 psi cap will prevent such problems. Finally, Miller recommends a fifty-fifty mix of water and antifreeze for coolant.
It took a little tweaking and trimming to get the radiator in place as the Chrysler and blower drive fills the engine compartment with little room to spare, but we're confident that going with the biggest crossflow radiator will help us keep our cool.
To accommodate the crossflow...
To accommodate the crossflow configuration, the stock core support and the inner panels had to be removed. We'll have to make new brackets for the tilt hood, and aluminum panels will be fashioned to fill the gaps between the radiator and fenders.
One of the advantages of aluminum...
One of the advantages of aluminum construction is it allows for the manufacture of large tubes. Our radiator has two rows of 1/2-inch tubes.
With the core support removed,...
With the core support removed, the fronts of the fenders were supported on jackstands. We used wood shims to get the exact height.
We opted for an AFCO aluminum...
We opted for an AFCO aluminum shroud and an S-blade electric fan, also from Speedway Motors.
Our Hemi has equipped with...
Our Hemi has equipped with adapters from Hot Heads that allow the use of a Chevy water pump. A flat piece of metal strap was tack welded to the fenders to hold them in place when the core support was removed.
To drop the radiator down...
To drop the radiator down below the edge of the fenders requires some surgery on the Fatman Fabrications frame stub. Notches were cut for the radiator's tanks then filled with pieces cut from rectangular tube. The right 'rail was also notched to provide clearance for the lower radiator hose.
The notch made for the lower...
The notch made for the lower radiator hose was filled with a patch cut from a section of an old driveshaft. Check out the quality of the welds on the AFCO radiator.
The tops of the 'rails were...
The tops of the 'rails were flattened slightly and the left side was notched for tank clearance only.
New radiator mounts were made...
New radiator mounts were made from 1-inch square tubing. They bolt to the frame to make radiator removal easy. Eventually, when the rollcage is added, these mounts will have tabs that attach to tubes running from the firewall forward.
Finding the right radiator...
Finding the right radiator hose can often be a challenge-steel tubes with 90-, 105-, and 135-degree bends with connector hoses on each end are real problem solvers.
Speedway Motors also offers...
Speedway Motors also offers cut-to-fit silicone hose with 45- and 90-degree bends in 1-1/2- and 1-3/4-inch diameters.
Another problem solver: stepped...
Another problem solver: stepped hose. It's available in 1-1/4x1-1/2- and 1-1/4x1-3/4-inch combos.
For anyone using an engine...
For anyone using an engine with a reverse flow cooling system (like an LT1) or has a cooling system that traps air, a bleeder in the top hose is the cure.
In some cases the filler on...
In some cases the filler on the radiator is either hard to get to or lower than the thermostat housing. This Speedway Motors filler neck can be installed in the upper radiator hose to cure both problems.
There are a host of parts...
There are a host of parts and pieces available from Speedway Motors that make radiator installations easier. These are spacers to be used for water pump pulley alignment.