Building Endurance – Performance Radiator Kit R&D, Part 2 – Primary Radiator Design Plans


The Toyota Supra is essentially the definition of automotive athleticism. It’s compact, agile, makes all of the right sounds, and the B58 is more than willing to give you a sharp shove back into the driver’s seat at a moment’s notice.  Though BMW/Toyota designed the Supra to be a top performer, even the most well-trained athletes can still succumb to the brutal heat. We here at Mishimoto already have the plans to keep the Supra running at peak performance.

If you remember back to our first post, and if you saw the sneak preview in our heat exchanger post, you might already know that it’s a group effort when it comes to cool this B58. The front end of the Supra houses a squadron of different heat exchangers for both the cooling and intercooling systems, all working in tandem to ward off extreme heat. While they work hard in their OEM form, some aspects could lead to your A90 trying to catch its breath on the side of the road. After some serious scanning and planning, however, Jason is ready to unveil our design that will improve your Supra’s endurance.

Ta-dah! It might not look like much now, but this is the framework for our radiator design. On paper, our plans will always work, but we have to make sure that all of the improvements can physically fit in the vehicle.

Our fitment prototypes serve as a means to ensure that our final design will fit without any issues once they arrive in our R&D facility. For now, though, it serves as the perfect physical manifestation of Jason’s vision to improve on the stock system, starting with the core.

In terms of exchanging heat, bigger is typically better. Well, scientifically speaking, the precise amount of increased core size will serve as an improvement over the stock unit. Even with the Supra’s long snout, there is still limited room to expand into, especially when combined with our expanded heat exchanger being developed right alongside this radiator. In that case, Jason is planning on expanding the core’s thickness out by 7mm for a total of 42mm. The increased core size allows for an increased coolant capacity along with more air contact with the external fins for a much more efficient heat transfer. Also, we plan on utilizing our louvered fin design to increase our radiator’s heat dissipation properties further.

When it comes to the end tanks, our plan is for a partial overhaul, meaning that we do intend to keep a few of the design features from the stock design. Specifically, we want to ensure that mounting and the integration with the rest of the cooling system are as simple as possible. In those cases, we’re opting to retain the stock style quick disconnect fittings so your hoses will clip straight into our radiator. We plan on leaving the mounting point locations alone as well for the sake of direct fit. Though the combined width our radiator and heat exchanger, some modifications may be required, but worth the effort. After carrying over the OEM design queues, we plan on ditching the plastic end tanks in favor of full TIG-welded aluminum construction, ensuring a sturdy connection between the core and the rest of the cooling system.

Even with its athletic prowess, the Supra still isn’t completely immune to the trials of extreme heat. However, we now have a plan in place to keep the temperatures under control with our new design. As the saying goes, “There’s no pr-I-mary radiator in ‘team,’” so, Jason has even more schemes to improve on the Supra’s cooling system with the auxiliary radiators as well.


Thanks for Reading!