Forgot to add that many competition rules don't allow the battery to be in the passenger compartment either ...

I had no idea heat was such as issue for the lithium batteries. I ran one in my daily (mazda2) for about 2 years before I sold it and had no issues, though I'm sure the rotary puts out more heat than the little 1.5 mzr motor. Maybe a custom box or heat shielding would allow a lithium unit to be used sucessfully.

It may depend on your brand, but the standard Odyssey battery is only rated for 115*F and the metal jacketed version still has a maximum 177*F rating. I even killed an Odyssey PC680 jacketed version with it between the engine and the radiator. Not to mention that it simply doesn't have enough overall capacity for this application, which also decreases as temperature rises. This car has a lot of electrical demand thanks to EPS. The alternator should handle that in most situations unless you have high underdrive pulleys at OE idle etc., but it simply doesn't take much to sap one of those small, low capacity batteries. The rotary engine also needs a strong starter rotating speed to fire off quickly moreso than a piston engine.

Best deal on Group 35 battery is the Costco battery - even looks identical to the Mazda OEM I replaced. See more at:

https://www.rx8club.com/series-i-tec...stions-264356/

https://www.rx8club.com/series-i-tec...-186805/page2/

Spent a day in the garage with some steel and a welder and made my own battery relocation.

I mainly wanted to free up air flow behind the rad and move some of that dead weight back behind the struts
https://cimg7.ibsrv.net/gimg/www.rx8...0efa5975a.jpeg

https://cimg8.ibsrv.net/gimg/www.rx8...21694478a.jpeg

https://cimg9.ibsrv.net/gimg/www.rx8...e074aee57.jpeg

Lots of room for a top mount turbo now... just sayin!

Nice work, but it's heat that kills batteries and that was my main reason for relocating it to the trunk.

I put one of these in the factory box (STX30L-BS):
https://www.batterysharks.com/Sigmas...-30-385-HD.htm

Seems to work well and saves a few lbs. The battery that came with the car had the terminal locations reverse from stock design, and was larger than stock. So neither the battery box or intake box fit properly.

If removing the battery and intake boxes improves cooling significantly, I'll consider a relocation in the future (and switch to a lighter lithium unit). Has anyone done testing with water temps on track with stock setup vs relocated battery and aem intake?

No turbo, just cooling and aero for now.
If anything I want that holy grail and put an additional dorito on that motor

Heat kills batteries so yeah, and trunk mount would be nice but there’s soooo much extra work that I don’t want to do. I guess you can argue welding and fabing is just as much work but I’m more willing to do that than run a ton of extra wiring and what not.

My main concern was air flow and weight out front of the struts but maintaining factory CA/CCA is key to longevity of the battery rather than being concerned about what the heat will do to it.

i.e. 3 rotor; in that case don’t forget to buy your lottery ticket today ...

Or go to Walmart and fall while buying a watermelon. Someone got seven million that way:

https://www.google.com/amp/amp.grubstreet.com/2017/11/walmart-loses-lawsuit-to-customer-who-broke-hip-buying-watermelon.html

Seven million could buy a lot of 3 rotors. Or one of Mad Mike's 4 rotors.

Thing is, you can't go to Walmart and fall on purpose. I think there's a name for that. Oh yeah… fraud.

Considering the fraud they commit on their employees, my name for that is ... just rewards. What they do to their employees to avoid paying the any insurance etc. benefits is criminal in my book. It’d be my dream that they crash & burn and all the mom&pop hardware etc. stores they ran out of business come back. Bottom line is that they carried everything to kill the competition, then the bean counters cut out all the stuff deemed non-profitable, and now you can’t find anything any place local. Everybody just carries the same generic basic crap from Asia.

Can’t say I ever approve of insurance fraud. That said, you bring up some good points.

yeah no kidding. I'm trying lol:lol2: