Despite literally just getting a new battery for the Evo (here), I wasn’t entirely satisfied with my choice and decided to swap out for a Deka ETX16L. There are a lot of options in this mid-range, and the Deka ETX16L is a ~17lb battery (12 lbs heavier than the Shorai, 11lbs lighter than the D51 “Miata” battery), and the full specs are listed here. As I understand it, the ETX14L & ETX20L are also popular choices. The ETX18L has a hair more CCA & capacity than the 16L, but decided the trade off would be fine, while still having more capacity than the 20L and way more capacity than the 14L, which was never on my list of options. This is a solid battery, with 325cca & 19ah. The car is never away from a tender for very long anyway, but still keeps in the spirit of being a street car, and with AGMs it should be able to go over a full week of discharge with absolutely no issue, and handle being discharged fine as well.
Installed with no issue & added a little bit of heat resistant tape to the side facing the engine also. Also worth noting, I added a good amount of the heat resistant tape to the areas of the coolant hose that comes closest to the engine & exhaust manifold. With the battery, I used the same battery mount kit that I did for the Shorai as they are near identical in volume. Also worth noting, these are the terminals that I purchased to go with this battery. I could have reused the ones I used on the Shorai, but they were too short for the evo’s adapters, which forced me to use tin foil to thicken the grip on the terminals – this is a better solution and a perfect for the fit for the Evo. Looking forward to the 2019 season soon!!
Old Shorai v. New Deka ETX16L
ETX16L weight (no terminals) – 16.6lbs:
Old “new” Setup (Yellowtop D51):
ETX16L installed & on the trickle charger:
Battery date & Heat tape added: