help me ID my diffs.

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dirtee-herbert
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Post Wed Feb 06, 2013 12:37 pm

Hello guys.

I have a 316i touring and a 318i auto saloon.

the tags on both the difs are rotten so i can not read what ratio they are.

I was wondering if any of you guys will know or can shed any light on what ratio they both are please.

I am sticking the 1.8L engine on the manual box and putting it in to the touring and i am wanting to know which diff would be best to run.
Grrrmachine
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Post Wed Feb 06, 2013 1:23 pm

Are the diffs off the cars?

Put some tippex on the input and output shafts, then turn the input and count how many times it turns the output.
daimlerman
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Post Wed Feb 06, 2013 1:31 pm

There is an original equipment diff table floating about the interweb thingy,I'm a bit suprised that it's not already been captured by the wiki men!

316i touring should be 4:45,or about 60mph at 3000rpm.

No idea about the auto,sorry.

a decent ratio to look for would be a 4:1,this gives 65mph at 3000rpm and was stock on 320i saloon and 318iS.
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age
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Post Wed Feb 06, 2013 2:20 pm

they are either 4.45's or 4.27's

either will be fine in your touring :)
M40 rightness if you can get to 6000rpm noone can hear your tappets
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dirtee-herbert
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Post Thu Feb 07, 2013 12:00 pm

Thanks for your replies guys. very helpful :)

The diff off the auto saloon is off the car. (car is compleetly stripped. loads of bits available if anyones interested)

The tourings diff is still in the car at the moment.

I will do the counting the turns aproach once both are off and fit the highest ratio of the two if they are any different.

I did play around with the diff off the saloon when i removed it and i helled one out put flange and turned the input flange and it felt knotchy. Is this right? How are they ment to feel? and how can i tell that the diff i fit is in reasonable condition before i fit it without a total strip down?

Thanks again. id rather ask lots of questions than fix potential mistakes later on.

:cheers:
Sanchez
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Post Sat Feb 09, 2013 12:15 am

Image