Westco 12V31M Miata Battery for Miata
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Westco 12V31M Miata Battery


PART NUMBER: 42-1007



No Longer Available
From Good-Win-Racing

No Longer Available
From Good-Win-Racing


The Westco Miata battery utilizes absorbed glass mat technology for approximately 30% more cranking amps than a stock Miata battery. With this latest design, terminal location is OEM correct and installation of this Miata battery is easy.

Voltage: 12
Amp Hour: 31
CCA 475*
Length: 7 1/2"
Width: 5"
Height: 7"
Weight: 25 lbs

Comprehensive Warranty: 4 Years - First Year Exchange, Balance Pro-Rated

FED EX Ground Service Only, lower 48 states USA only (no Hawaii or Alaska).

*UPDATE 2014: The battery industry has done away with in-house testing, the 475 CCA was based on in house room temperature Midtronics tester, but starting this year these ship with independent lab test spec of CCA measured at 0 degrees F for 30 seconds (which is 320 CCA for this battery). Same battery, just a much more demanding test that may or may not reflect your local conditions. How many of us live in 0 degrees? Here in San Diego average day is 70 F and the battery can make 475 CCA here. Regardless, for those who have used and depended on Westco for all their Miatas going back two decades just understand the battery and the CCA it offers hasn't changed, just the testing standards.





Customer Reviews

Westco 12V31M Miata Battery

Solid. Works like a charm. It's snug too. My battery died on me and now I can drive my miata to my buddy's place to swap my engine.

Perfect fit, good life, usually last 5-6 years, consistent quality. Kept on trickle charger in between track events.

The Westco battery is simply the perfect replacement battery for an NA Miata. The Westco I replaced lasted about 8 years, parked outside thru 8 cold New Jersey winters. The Westco fits perfectly, has the terminals on the exact right locations for the stock wiring, and mates perfectly with the stock battery tie down. It also has the little ports for the vent tubes to route any gasses out of your trunk. It arrived in perfect condition, with a strong initial charge. This is the only battery I'll ever buy for an NA or NB Miata.

This is the one you want for a Miata. They last five or six years. They fit perfectly. They are maintenance free.

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