Just been looking around at options for batteries for the Roadser, and have found there's a lot of incorrect information that suppliers have as to what fits the Roadster.
NOTE
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Before using any of the below, CHECK the battery on your car and measure the terminal posts
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- you often cannot return batteries once purchased! Japanese ones are 14mm and 13mm in size,
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'European' size posts are 19.5 and 18mm.
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Posts are usually slightly narrower at the top than the base.
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So, hopefully this will be useful for anyone looking to replace their battery in future.
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I've also been specifically looking at
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'upgrades' over standard batteries for use in the car, with a higher engine cold cranking capacity.
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Problem I've got
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- my Toyota
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'Optifit' battery has been flat a few times and although will start the car fine, the Profec e-01 display will not start correctly every time.
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As the engine cranks, there's corruption on the display
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- this gets worse in the cold, which I suspect is due to the supply voltage dropping as the engine cranks.
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Trying to clean up the supply
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( capacitors, diodes) has helped a little, but not cured the problem.
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Also, charging my Optifit battery I don't get the
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'green' signal in the indicator glass, but a black one
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- indicting the battery is probably partially sulphated and on its way out.
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The Battery in my car has
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'thick' European posts, as opposed to the
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'thin' posts on Imports.
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The Positive terminal is also on the right, as viewed from the rear of the car.
Halfords
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Worth noting they do free battery checks, and can also check your alternator is charging and the regulator is working correctly.
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They've got a BOSCH tester to do this for them automatically
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- well worth doing if you think you've got problems.
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For reference, the Standard Halfords battery did well in an AutoExpress battery test a few years ago, so would be one I'd consider for the
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'2.
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Their Guide Recommends the HB053 battery
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- correct size, correct location of the
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+ve on the right BUT has thin terminals so not correct.
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Looking on the shelves, the HB057 has the correct thicker terminals, is the right size
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- but the
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+ and
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- terminals are on the wrong sides.
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Looking at my car, there appears to be enough slack the battery cables to stretch to reversed terminals if needed, but didn't check further.
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Cost
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-
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£59ish for either currently.
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However, there was no
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'performance' Calcium or Silver variant available
Other Alternatives
: Bosch, Varta, Exide and Optima ![](./images/smilies/spacer.gif)
Bosch
/ Varta ![](./images/smilies/spacer.gif)
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Bosch and Sister company Varta both do batteries but again the online recommendation tools were wrong for my March
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'03 car
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( They recommended thin Japanase spec post batteries
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)
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Bosch do a S4 series battery, with thick posts which is S4021
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- the thin post variant is S4020 which look to fit.
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Its not clear if this is a performance variant, but its CCA spec is the same as the Halfords one.
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( 330A, and 45ah Capacity)
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Their sister company, Varta do list two batteries
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- from checking all their online datasheets I've managed to work out which ones are correct for me
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:
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First, one with narrow posts
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( which isn't right for my car
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) and claims Calcium
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/ Silver technology but the CCA is 330A
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- about the same as a standard battery.
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Details are B31, Varta DIN ref 545 155 033.
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Checking their datasheets, the 545 156 033 is the same battery but with thick battery posts
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- which is what my
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'2 needs.
Exide![](./images/smilies/spacer.gif)
I did find an Exide battery to fit, but it was a
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'basic' model
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- I'd hoped to find a premium Silver
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/ Calcium technology model but they don't do one.
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Given Halfords batteries out performed standard Exide batteries I didn't go any further.
Optima![](./images/smilies/spacer.gif)
I've actually gone for an Optima battery
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- the Yellow Top D51R with reversed terminals, which is the same physical size as the standard battery.
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see
http://www.tayna.co.uk/Optima-Yellow-Top-P3802.html
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Googling, you'll find lots of material about Optima batteries
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- they're made by a Swedish company, with their original application being motorsport.
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The only one that fits the MR2 Roadster is a
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'deep cycle' Yellow top battery.
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Deep cycle batteries normally aren't used for road cars as they don't provide the starting current needed- but the Optima's construction and the use of glass matting and spiral wound cells means it has exceptionally low internal resistance and is able to provide the high current needed to crank a cold engine
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- its capacity is a massive 460CCA.
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I noted top end Bosch batteries are also offering batteries on this technology for applications other than MR2s
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- their price is around
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£130-150.
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Cost of the Optima is
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£175 delivered
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- not cheap
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- but I'm looking forwards to getting it fitted into the
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'2 this weekend and with the big improvement in the cold cranking capacity hopefully should sort the problems I've been seeing with the Profec controller's screen.
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I'll post back with views and some pictures once it is in the
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'2.
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