325 diff ratios

Tue Nov 24, 2015 6:24 pm

Hi am I right in thinking that a 3.91 differential is the best for acceleration I can get for my 325 sport, thanks[/i]

Tue Nov 24, 2015 7:33 pm

Tue Nov 24, 2015 9:09 pm

according to the wiki, some sports came out with the 4.1 in medium case, 3.91 would be more readily available.

http://www.e30zone.net/e30zonewiki/inde ... fferential

Tue Nov 24, 2015 9:52 pm

No 325i sport ever used the 4.10 ratio or any other 325i for that matter.

Many mistakes in that wiki diff ratio guide.

That's not to say a 4.10 medium case can not be used, but you would need to get one from a US spec M3 and it would also make it rev very high at motorway speeds.

A 3.91 is about the most you would want to go.

Wed Nov 25, 2015 6:51 am

Barry, that diff table is one of the oldest pages in the Wiki, so if you can give me some pointers about how it needs correcting then I'll clean it up ASAP. I've never seen any sources for the information that's on there.

Wed Nov 25, 2015 9:10 am

Grrrmachine wrote:Barry, that diff table is one of the oldest pages in the Wiki, so if you can give me some pointers about how it needs correcting then I'll clean it up ASAP. I've never seen any sources for the information that's on there.

Thanks, that would be great, us newbies treat it as gospel

Sat Nov 28, 2015 1:26 am

I've recently swapped the engine in my 320i for a m20 2.5. I kept the 240 gearbox and the original diff. According to the zone wiki my car came with a 4.45/4.27. What I can say is acceleration seems quickish and it hits around 3200 maybe a touch more at 70 mph running 16" wheels.

Don't know if this information helps you but hopefully it does..

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