Maybe you're restoring your Corvette or just can't stand another hot summer with the A/C turned off because your Corvette runs too hot. It's probably time to replace your original copper/brass radiator with a high-efficiency aluminum unit. You know what we mean. You can run the A/C as long as you're moving at highway speeds, but even at speed, the temperature is elevated. When you sit in traffic and idle for a while, the temperature continues to creep up and your anxiety builds. You've tried all the easy stuff, including a lower temperature thermostat, maybe added an electric fan (if you have an engine-driven fan), or possibly tried some miracle cooling liquids. Nothing you have done so far has helped. No problem. A new aluminum radiator can save your Corvette from major future damage.
Aluminum radiators are, in most cases, at least 30 percent more efficient than copper/brass radiators. The primary reason is aluminum radiator tube configuration allows more tube surface to air than copper/brass radiators. There are a few manufacturers in the aluminum radiator game now. We decided on a Dewitts radiator for Project Shark Attack because their radiators are Direct Fit, a complete drop-in with no modifications. One thing we didn't need was more fabrication during the assembly of PSA.
Dewitts specializes in Corvette radiators, and they also understand how particular Corvette owners can be about the fit and finish of their Corvette. The Dewitts radiator is unique because the tanks are stamped and, for all practical purposes, resemble the factory copper/brass tanks. The radiator inlet and outlet positions are also in the same location as the factory unit it replaces.
The coat of black paint on a Dewitts radiator requires a double take-you think you're looking at an original copper/brass unit. Dewitts has a black ice coating they can apply to the radiator if originality concerns you. The black ice coating is formulated to give you the original look without the heat transfer concerns of traditional paints. The welded tanks to the radiator core might give it away, but that's OK. The welded tanks mean no epoxy to act as a heat sink.
Our radiator core support was junk (like most are). We originally thought we could save ours, but once we cut into it, the rot was much worse than we thought. New radiator core supports have been difficult to find in the past. Luckily, Dewitts had one available. We didn't want to compromise the radiator install with a weak radiator core support or have the nose of the PSA drooping.
Although we decided to use electric fans on this project, they are not mandatory. The aluminum radiator will make a significant difference and work fine with an engine-driven cooling fan. The problem with engine-driven cooling fans is they work best when you need them the least. Electric fans, when controlled properly, will keep the engine temperature stable no matter what the ambient temperature is.
Once the radiator is installed, be sure to check for electrolysis from a poor chassis or radiator core support ground. The electrolysis will eat the aluminum up in short order. One telltale sign is a black anodized look inside the radiator tanks. When you service your cooling system, the electrolysis check should be performed. If you find electrolysis, and you've been running the engine like this for awhile, fix the problem and change the antifreeze.
Use aluminum fittings in aluminum radiators, if possible. Using dissimilar metals together can also cause electrolysis and corrosion. A light coating of Teflon sealer on fitting threads is a good idea for ease of removal later. No need to use the longest wrench in the toolbox to install the fittings either. Use restraint when tightening the drain plug or drain cock.
We dropped our Dewitts radiator and core support into PSA and filled it with a 50/50 mix of Prestone antifreeze and distilled water, then hit the road to catch up with the '05 Hot Rod Power Tour. During the trip, the cooling fans would come on at 215 degrees, run for a short time, and the temperature would quickly drop to 197 degrees. We ran the A/C through all the typical traffic associated with the Hot Rod Power Tour and never saw the temperature above 215 degrees. Out on the road, 200 degrees was the norm, no matter what terrain we encountered. since that time, the cooling system has continued to perform flawlessly, and if we ever need to service the radiator, the original engine-driven fan shroud is not a concern.
PSA had logged over 10,000 miles in seven months when we decided to take the cover off the top of the radiator and found quite a bit of debris had accumulated in front of the radiator. There had been no noticeable temperature change, but eventually, the accumulation of debris would be noticed. It's a good idea to annually inspect the area between the radiator and A/C condenser for debris.
Fuel mileage is our big concern now. The Dewitts aluminum radiator can actually save some dollars in fuel costs. If the electric cooling fans are controlled properly, the stable engine temperature will allow optimum fuel usage, and if the fans aren't running all the time, the alternator load will be reduced, thus using less horsepower, which means more fuel mileage. Even engine-driven fans will benefit if a thermostatic fan clutch is used. Lower temperatures will require less thermostatic fan clutch engagement, requiring less fuel usage. What a deal-save your engine and better fuel mileage to boot!