We vapor blasted our radiator lines to match the finish of the rest of our engine bay.
I am a big fan of the vapor blasted finish, and TSR Mario’s welds look amazing as always.
The upper radiator hard line fit perfectly and is a very clean installation. The line coming out of the radiator end tank was tilted at an angle to end up directly on top of the crossmember support brace. We designed the radiator to have this clean of a layout, which will also give us a lot of clearance for our turbo.
At the bottom of the car, we can see the radiator outlet, and the suction side for the water pump inlet.
The new low-pressure coolant hardline looks like it was designed from the factory. Cold coolant can now be pulled up into the engine by the water pump from the bottom of the radiator outlet. We were very happy with how everything laid out in the packaging of the coolant system.
CONCLUSION:
With the front bumper on, the 56mm cross-flow, dual-core, dual-pass Billy Johnson Racing (BJR) FD RX-7 Radiator fits nicely in the 1999+ FD RX-7 bumper. In this V-mount configuration, all the air entering the front bumper will be forced through the unobstructed A/C condenser for maximum A/C performance, and then the radiator, while the fresh air will be shared with the intercooler and turbo inlet. The Hayden (776) “HD COOL” Heavy Duty Oil Cooler is keeping our power steering in check and the twin 11” GC Cooling 1190CFM fans should be more than sufficient for keeping things cool at low speeds. The Raceonly Billet AST Delete looks great and really simplifies the engine bay by ditching the AST tank.
INITIAL TESTING
Project FD RX-7 is up and running! We still have a few more articles to catch up on but from initial street testing of the radiator we are seeing the coolant temps of 165-180*F on an 80-90*F day at speeds above 40-50mph with no radiator fans. At relatively low speeds, the inlet ducting is doing a great job at forcing all of the air through the radiator and keeping the temps pegged against the thermostat opening temperature.
During initial tuning and staying stationary for long periods of time on an 80-90*F day, only 20% duty cycle from a single 11” GC Cooling High Performance Puller fan is required to keep the engine temperatures in check. We were pleasantly surprised to see such little duty cycle and fan speeds to keep everything cool.
Overall, we are extremely pleased with the initial performance of the Billy Johnson Racing FD RX-7 V-mount radiator setup. There is still a lot of testing to be done. We will be charging the A/C system soon which will put some heat into the radiator and now that summer has started, we are looking forward to testing the performance of the JP3 RX8 A/C system upgrade and our new cooling system in traffic, as well pushing the cooling system on the track as we increase the power. Stay tuned!
If you are interested in purchasing the Billy Johnson Racing FD RX-7 radiator, please contact HQ Engineering at: [email protected]
5 comments
Fantastic update and all the custom work on the cooling system is so cool to read about. I am patiently waiting to see this thing finally unleash some HP!
Technically, you should have a ‘blade’ that bifurcates upper, and lower flows at the start of the duct. If you modeled this in CFD, there would be obvious turbulence that could easily be avoided.
Cheers.
Was about to comment the same thing.
Also, the air out of the IC needs to go somewhere… I don’t remember what the hood looks like for this project, but a proper vent with gurney flap and ducting would do wonders at speed.
Can’t wait to read the next articles.
It’s not that crucial to bifurcate the ducting. Many morern OEM cars don’t separate the inlet ducting of a common duct/plenum that feeds multiple heat exchangers because airflow is not laminar in the ducting and the important aspect here is creating a pressure differential across the heat exchangers. Proper ducting that seals the air from the front bumper to the heat exchanger creates a high pressure area on the front side of heat exchangers in the V-mount setup (or “L”-mount in many OEM applications) when using a common plenum (or air box, or radiator ducting).
I am currently in my FD build and would love to have one of these radiators, could y’all please guide me in the right direction to purchase one if they are available. I left a message on the BJR site to no avail. HELP…..someone??