Adding an aftermarket radiator to a Tri-Five can bring about various decisions that need to be made. For instance, do you want a downflow radiator that will fit in the OE location, or can a crossflow unit be retrofitted. The primary factors that will determine whether a downflow or crossflow radiator is right for your vehicle is predicated by personal taste and the space under the hood.
While downflow radiators are taller rather than wider, crossflow radiators are usually wider than they are tall. Because of the added width of a crossflow radiator in a Tri-Five, many times, the unit is mounted in front of the core support, and modifications are needed to complete the install. You will also need to decide whether a brass and copper radiator is for you, or will an aluminum cooler be a better choice?
We're not going to get in-depth with images showing how to remove the original radiator as we're certain you have that knowledge. But it is the first step.
When comparing copper/brass radiators to those made of aluminum, it’s important to consider the materials used and their advantages and disadvantages. A common misconception is that aluminum transfers heat more efficiently than copper. This is simply not true. If only speaking of copper and aluminum as simple materials, copper will transfer heat more efficiently. Unfortunately, copper is too soft to be solely used to build a complete radiator. Because of that, zinc is added to copper to create a brass alloy which helps the radiator get its rigidity.
Using some cardboard, shim the radiator up from the splash pan. Just raise it high enough so the top of the radiator is flush and level with the top of the core support upper bar.
Brass is a much stronger material and is very suited to build radiators. However, brass does offer less efficient thermal conductivity than simple copper. In fact, brass even offers roughly half the thermal conductivity of aluminum. While copper is a better heat transfer material, by combining copper and brass in a radiator’s construction, yields nearly equal heat transfer capabilities of an aluminum radiator – when talking only about the materials used to build the radiator.
It is true, an aluminum radiator can cool better, but as stated, that is not because of the materials used. Rather, the improvement comes about because it can be made to cool more efficiently. An aluminum radiator cools better than a copper/brass radiator, is because the aluminum is more rigid. This affords the ability to create larger cooling tubes in the radiator core to route the heated coolant through the radiator. For example, an aluminum radiator with two rows of 1-inch tubes has the equivalent cooling capability of a copper/brass radiator with five rows of 1/2-inch tubes.
With the cardboard spacers in place, position the radiator in front of the core support. The radiator's mounting brackets are spaced far apart to span the stiffening ribs in the stock filler panels. When the radiator is in place, trace the position of the upper and lower hose outlets onto the filler panel with a silver Sharpie or paint pen. Then, remove the radiator and set it aside. Once you have the holes made, it is also a good idea to use a grommet or split a piece of vacuum tubing and use it around the hole to prevent chafing.
Aside from the thermal-property differences of the radiators, there are also a few other important advantages gained by using an aluminum radiator. Two primary factors to consider when evaluating why an aluminum radiator might be a better option than a copper/brass radiator in regard to overall vehicle performance and cooling ability, are the structural strength (we already discussed), and weight reduction. Aluminum radiators are much lighter than copper/brass radiators.
Like you did with the radiator-hose holes, center punch and drill a pilot hole at each location for the transmission cooler lines (if needed). We drilled a 1 1/8-inch hole and then used a rubber grommet to finish off the holes.
For many, any weight reduction is a must-have aspect to an upgrade to their vehicle’s performance. Depending on the amount of weight reduction, an improvement in acceleration, braking, and fuel economy can be had. In the case of a radiator, it is minimal, but nonetheless evident. A properly constructed aluminum radiator provides high-efficiency cooling, is lightweight, and has a longer life expectancy when compared to copper/brass. Three benefits that are hard to deny.
Next, position the radiator in place and get it set where you want it. Mark the center of the mounting holes with your silver Sharpie or paint pen. Using a 3/8-inch drill bit, make the four holes in the core support filler panels. Put the radiator into place and bolt it in using the button-head Allen bolts, nuts, washers, and lock washers.
As previously stated, copper is very soft, and aluminum is much stronger and more durable. This aspect not only allows aluminum radiators to feature larger tubes which allow a greater volume of coolant to be circulated — and ultimately cooled, the strength of the aluminum tubes also allows for higher cooling-system pressures, which can actually allow a smaller radiator to cool better.
In short, aluminum radiators mark a modern advancement in cooling. Not only does the material dissipate heat at close to double the rate when compared to brass, but also reduces the overall weight of the vehicle and provides a stronger and more durable core and tube design. All these factors clearly lead to an overall increase in vehicle performance.
You will probably need new radiator hoses since the radiator has been relocated. We used a stainless-steel hose kit from Flexi-Kool. Not only do they give a custom look, but they allow you to bend the hose to whatever configuration you need, and then just trim to fit. You will also need to "tweak," extend, or replace your transmission-cooler lines as the radiator is now farther forward than it was when stock.
When thinking about upgrading radiators, an issue that plagues many Tri-Five owners, is the original (and even many aftermarket) radiators are a downflow design, not a crossflow design. With a stock 283 or 327ci engine, a downflow works fine. But, add some serious horsepower, and that old design can be inadequate.
A triple-pass radiator increases cooling capability by forcing the coolant to make multiple passes through the radiator before it returns to the engine.
Each design carries its own advantages and disadvantages. A downflow radiator design has the tanks located at the top and bottom of the core. The coolant enters through the top tank and trickles down through the tubes. With a crossflow design, the tanks are located on the sides of the radiator’s core, allowing the pump to push the coolant across the core from right to left. Crossflow systems are also offered in a single, double, or even triple-pass orientation.
To control the fans on our new radiator, we are utilizing a Painless Wiring fan controller (PN 16322) Painless recommends the controller be mounted away from heat, so we fastened it to the frontside of the core support.
A single-pass radiator is one that flows one way — be it from top-to-bottom or side-to-side. A triple-pass radiator is actually divided internally. Hot coolant enters the radiator, flows from one side to the other, turns and goes back to the other side, and then makes one more turn and then exits the radiator. The benefit of having multiple passes is, the coolant spends a longer time exposed to the core, which adds extra time for it to cool your engine even better.
We decided to use Evans Waterless Coolant in the Tri-Five's cooling system. The key to setting up your cooling system for waterless coolant is getting as much water out of the system as possible. When you complete the installation, you want no more than three-percent water in the system. Any more, and the effectiveness decreases drastically. Using the Evans Coolant Conversion Kit and the Prep Fluid, you should be able to hit this number with no problems.
Switching from a factory-style downflow design to a crossflow can be an easy conversion according to the folks at Danchuk. They offer a several radiator designs to fit in front of the core support that deliver crossflow capability and improved cooling. The radiator we’re featuring here is an all-aluminum, fully polished crossflow system with shrouds and dual SPAL fans.
Although this upgrade does requires simple modifications to your hot rod, the benefits are well worth the time invested.
With the help of Danchuk Manufacturing, an overly warm engine will be a thing of the past. If you’re concerned about converting from a radiator positioned behind the core support to one in front of it, don’t be. The install can be completed in a day with some simple hand tools. What’s more, once you are finished, you’ll have a truly cool-running hot rod.
Gaskets and Seals
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