As we’ve discussed before, rotary engines make a lot of heat, and the RX-8’s Renesis 13B is no exception. As Jim Mederer from Racing Beat explained to us, one of the reasons the Renesis runs hot is poor airflow through the radiator because of how jam-packed the engine bay is. More specifically, the huge OEM battery and battery box that’s mounted tightly behind the radiator on the passenger side is a major airflow impediment. To give you an idea how poor the airflow is here, the RX-8 has an air duct to the bottom of the battery box to help keep the battery cool. Although kits exist to relocate the battery within the engine bay (mounting it against the firewall where the windshield washer reservoir normally lives), we prefer the trunk-mounting approach using a dry cell (sealed) battery. We like the idea of moving a bit of weight to the rear of the car over the drive wheels, and we also like the fact that the Odyssey PC680 battery we installed is a whoppin’ 26 lbs lighter than the OE battery. As you can see, the installation is relatively straightforward, and for you DIY types who don’t have a welder, you should still be able to use the West Coast Batteries hold-down box we used (which is specifically designed for the Odyssey PC680 battery) by bolting it to the sheetmetal bracing behind the rear seats. As you can see, removing the OEM battery frees up a huge amount of real estate directly behind and above the radiator, allowing better airflow through the rad.As you can see, removing the OEM battery frees up a huge amount of real estate directly be To send power to the positive terminal on the battery, we ran 4-gauge industrial wire through the firewall and along the passenger side doorsill, under the rear seat and trunk carpet to the spot we chose to mount the battery.To send power to the positive terminal on the battery, we ran 4-gauge industrial wire thro Sasha Anis from SG-Motorsport welded four retaining nuts to the trunk floor (don’t worry, we threw some paint on the bare metal afterward to prevent rust from forming) so that we have a very secure method of bolting down the West Coast Batteries hold-down box and Odyssey PC680 battery.Sasha Anis from SG-Motorsport welded four retaining nuts to the trunk floor (don’t worry, With a quick coat of flat-black paint on the hold-down box and a ground wire running under the carpet to a suspension stud on the trunk floor, we’ve got a nice clean install.With a quick coat of flat-black paint on the hold-down box and a ground wire running under To complete the wiring, we simply bolted the 4-gauge red wire’s ring terminal to the OE positive terminal on the factory wiring harness and grounded the harness to the crossmember using the OE ground terminals. The OE wiring has been left completely unmodified, so we can easily revert to the stock battery setup for winter driving.To complete the wiring, we simply bolted the 4-gauge red wire’s ring terminal to the OE po Source box Odyssey PC680 Dry Cell Battery odysseybattery.com 877-297-3815 West Coast Batteries, Inc. Aluminum Hold-down Box westcoastbatteriesinc.com 888-379-2555 SG-Motorsport Wiring & Welding sg-motorsport.com 905-463-1483 SOURCEBOX West Coast Batteries 410 Le Roy Drive Corona CA 92879 888-379-2555 www.westcoastbatteriesinc.com SG-Motorsport 905-463-1483 http://www.sg-motorsport.com Odyssey Batteries 2366 Bernville Road Reading PA 19605 800-538-3627 www.odysseybattery.com By David Pratte Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!
