Mark Houlahan
Brand Manager, Mustang Monthly
January 1, 2013
Even though our radiator was built from our specs to fit, there is still a fair amount of mock up work to do to finalize everything.

If you have a 1968 Mustang with the typical small- or big-block Ford engine offering between the framerails, you can source a direct-fit bolt-in radiator from one of a dozen or more different sources. A few days later, a big brown truck pulls up to your driveway and drops off your shiny new thermal transfer unit—it will probably take you less time to bolt it into your Mustang than it will to get it out of the shipping box. However, things change when you start deviating from stock. The most basic of upgrades, like a serpentine pulley setup, for instance, might relocate the water pump inlet from one side of the block to the other. Uh-oh, your stock radiator no longer works. A solution might be as simple as a custom lower radiator hose. There are a few "custom" radiators on the market for the most popular upgrades like '87-'93 5.0L Mustang engine swaps, but when you really start “going wild,” your best option is going to be ordering a custom radiator to work with your choice of engine and other major mods.

In the case of our project 1968 Mustang fastback, Generation Gap, we not only have a 4.6L Three-Valve modular engine under the hood, but we no longer have the OE strut rod mounting brackets welded in place either (which are used to mount the bottom brackets for the larger big-block radiator setup). We wanted an OE fit to our radiator that would allow us to use our stock modular engine cooling hoses, fit the '68 Mustang's radiator opening, and of course, have plenty of cooling capacity while using an electric fan—there's no provision for an engine-driven fan with 4.6L Three-Valve Mustang engine. We've used direct-fit products from Flex-a-lite before and have been extremely pleased with their hardware, fit, and cooling ability, so they were on our short list of companies to touch base with. When we found out they have a custom order program to build a radiator exactly to your project's specs, that sealed the deal for us.

We got on the phone to Flex-a-lite's David Heutmaker to discuss our needs. After taking a few measurements, David recommended Flex-a-lite's 52180R universal radiator as a base for Flex-a-lite's custom shop to build from with our needs (inlet/outlet sizing and location, and so on). As you'll see in the photos, David's recommendation was spot on.

Flex-a-lite's radiators all begin with a two-row, all-aluminum core—down flow and cross flow, as well as a dual-pass cross flow, are all options. Side tanks are built using the company's patented Flex-a-fit T-channels that not only help dissipate heat by increasing surface area (both inside and outside the tank walls), but allow custom mounting solutions that do not require welding brackets in place. The T-channels also allow custom mounting of additional accessories like overflow tanks, cooler mounting rails, and more. Best of all, Flex-a-lite's radiators are all proudly made in the USA and are welded by hand for great looks and top quality, fit, and finish. Turnaround time on a custom radiator is a couple of weeks, plus shipping to your location, but the end result is a radiator that fits your one-off application like a fine Italian leather driving glove!

Cooling System Part Numbers Used
Flex-a-lite
Custom Radiator PN 52180R $940.96
TransLife Cooler PN 4190-6 $247.94 (4116-6 without fan, $55.98)
Accessory Bracket kit PN 32122 $32.05
Gator Clamps PN 3926 $14.13
Zinc Anode PN 32060 $10.84
Summit Racing
180 Fan Switch PN DER-13021 $27.95
20ft of -6 PTFE hose PN SUM-220985 $62.99
-6 AN 45 Fittings PN SUM-220144 $11.95 (each)
Total Cooling System $1,384.66 ($1,192.70 with 4116-6 cooler)

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