Diff ratio

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scjimbo
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Post Fri Aug 17, 2012 8:43 pm

I have a pre facelift 320. I'm looking to buy a diff to renovate off the car then put on to replace mine.

What's a good ration to get, and indeed any ideas what ration mine would be as standard.

CIA
scjimbo
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Post Fri Aug 17, 2012 9:07 pm

Further to the above at this juncture I have to admit I know diddly squat about diffs. When i say ratio I mean 3:64 or whatever it is. :mad:
vokietis
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Post Fri Aug 17, 2012 9:10 pm

prefacelift might be 3.45 ratio
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jmc330i
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Post Fri Aug 17, 2012 9:26 pm

Pop your VIN (usually last 7 digits) into realoem and it should only list the parts for your car, you can then see what ratio it left the factory with.
James
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Post Fri Aug 17, 2012 9:34 pm

scjimbo
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Post Fri Aug 17, 2012 9:40 pm

cheers grrrrr
scjimbo
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Post Fri Aug 17, 2012 10:44 pm

I've heard the ratio is cast into the diff. Where abouts is it on the casing?
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AlpineCab
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Post Fri Aug 17, 2012 10:48 pm

there should be metal tag on the diff case. give it a clean up and reveal the number!
Duke137
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Post Fri Aug 17, 2012 10:53 pm

scjimbo wrote:I've heard the ratio is cast into the diff. Where abouts is it on the casing?
Not true, it is a little tab on bolted to the back plate, 30% of the diffs I have don't even have one and the rest are unreadable without a wire brush on a drill :)
How do you pronounce 'either'? I say 'either', but some say 'either'. Either is correct.
scjimbo
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Post Wed Aug 22, 2012 7:23 pm

jmc330i wrote:Pop your VIN (usually last 7 digits) into realoem and it should only list the parts for your car, you can then see what ratio it left the factory with.
Right I got my V5 back today from DVLA so put the details into real oem. Really not sure if I'm using it right. I go through to the parts list after I put in my number to my diff. Its not giving me the ratio but it is saying I have a limited slip diff and i don't get any other options. Is this possible on my car. Pre face lift 320 2 door?

CIA