We mounted the Hayden “HD Cool” 778 oil cooler to the chassis with 3 simple brackets. We installed oil cooler ducts to the front bumper which determined the mounting location and angle of the oil coolers to ensure a proper seal.
One of the most overlooked aspects of cooling is the ducting. Whether it’s a radiator, intercooler, oil cooler, or any drivetrain heat exchanger, proper ducting can DOUBLE the cooling ability of a heat exchanger over one with zero ducting. Typically, a 20-50% improvement can be easily found. Air takes the path of least resistance, which is usually around a heat exchanger rather than flowing through it. Properly sealing the duct to the core of the heat exchanger creates a pressure differential across the core, which is key for improving cooling efficiency.
We found these fiberglass oil cooler ducts for the 1999+ FD front bumper.
The ducts sit flush against the factory front bumper and we used High-Temperature Silicone Rubber Foam (PN: 4869A3) rated to 450*F to seal the duct to the face of the oil cooler.
Duct Tape was used temporarily to hold the duct to the front bumper for fitment and mounting of the oil coolers. We will later use fasteners to secure the duct to the bumper.
With the front bumper back on, the ducts provide an air-tight seal to the face of the oil coolers. This will greatly improve the cooling ability and efficiency of our oil coolers.
With proper ducting, the large 21-row Hayden Automotive “HD Cool” (778) oil coolers look great behind the front bumper. The cooling ability of our 13B has now been significantly improved and ready to be put to the test on the track!
Quick Reference:
Page 1 – Stock FD RX-7 Oil Coolers
Page 2 – Hayden HD Cool 778 Oil Coolers
Page 3 – Oil Cooler Ducting
Page 4 – Improved Racing Remote Engine Oil Filter Mount & Thermostat
Page 5 – How to Make Earl’s Performance Stainless Steel Hose
Page 6 – Oil Plumbing Series vs Parallel & Radium Low Profile Swivel Fittings
Page 7 – Raceonly Billet Remote Oil Filter Pedestal & Front Iron Oiling
Page 8 – Raceonly Billet Oil Filler Neck & Improved Racing Catch Can
Page 9 – Crank Venting from Gutted OMP Port & Turbo Drain Fittings
Page 10 – Raceonly Billet Power Steering Reservoir
11 comments
I don’t think I could park this thing on the street knowing the man hours invested.
Good job. Helluva build.
This has been a great build to follow along. I noticed in the radiator articles you were calling it the BJR radiator. Are there plans for some of these parts to go into production?
I called it the Billy Johnson Racing (BJR) Radiator to give it a name because it was a custom build to my specifications for the FD platform. I’ve sold a few to people who reached out to HQ Engineering and ordered one, but this is a high-end motorsports radiator that’s priced in line with similar 50mm motorsports radiators (>$1,000) that should outperform anything on the market from my research based on its dimensions and efficiency (that fits within stock frame rails). The majority of FD owners are street guys who are use to $400-500 drop-in replacement radiators that are only slightly better than stock. If you need a significant improvement in cooling, you’ll have to spend more than double that wherever you go.
Thank you 🙂 It’s far from over…
Wow, beautifully done!
Out of curiosity why did you go with stainless braided lines over nylon braided? I’ve been choosing nylon braided lines since they’re lighter and easier to work with but I don’t have the experience with A/N lines you do.
I’m a big fan of nylon and use it in many applications, especially for those areas that will not see abrasion or impacts. We chose stainless because it was the only option at the time in the PTFE UltraPro -10AN hose, stainless is generally better protected for mission-critical fluids like oil lines that might see debris impacts, and because this new hose is so flexible and light, there really aren’t any downsides other than maybe a few ounces per foot. This -10AN is very light (37% lighter than traditional rubber w.stainless braid) and is extremely flexible with a 1.772″ minimum bend radius (vs 6.0″ minimum bend radius for the all-rubber Super Stock hose and 4.0″ for the rubber-lined stainless steel braided Auto-Flex hose). The UltraPro and new Ultra Flex 660 Stainless & 650 Kevlar Steel & Pro-Lite 390 Nylon hose are a significant improvement in quality than the impression that you or I might have on thinking of Earls as old-school, old-technology ‘hotrod’ hose vs many high-end motorsports hose brands. I’d bet that once you experience UltraPro & UltraFlex hose first hand, you’ll change your impression on Earl’s, like I did.
Thanks for the info Billy. I’m actually working on an oil cooler and catch can setup for Project EF Civic. I was going to use Earl’s nylon braided line but I will definitely take a look at the UltraFlex lines for the cooler itself. It’s a shame this sort of info isn’t easier to find on their website.
Happy to see that parallel flow oil cooler setup. A bit curious to hear that in prior history, others’ experience with the parallel vs series flow didn’t show dramatic differences in performance. I wonder if that was due to airflow restriction of the factory bumpers. Anyway, the reduction in pressure drop is worth the parallel setup alone. But I expect your setup to do well as you’ve properly accounted for the airflow.
Any particular reason you went with the Radium catch can over the Improved Racing one? Or just personal preference.
Love the update. Love all the blue anodized parts. Love the attention to detail.