Looking for 3.25 differential for early CSi

[Memo]

It looks like I’m in urgent need of a bog standard 3.25 differential for my ’72 CSi. Preferably from Europe to save time.

Any suggestions would be greatly appreciated.

BR Memo

 

[Jahan]

It looks like I’m in urgent need of a bog standard 3.25 differential for my ’72 CSi. Preferably from Europe to save time.

Any suggestions would be greatly appreciated.

BR Memo

Hi:
I just listed a Limited Slip 3.6 if you are interested. Can be converted to 3.25!
I am in Virginia , USA

 

[Memo]

Hi:
I just listed a Limited Slip 3.6 if you are interested. Can be converted to 3.25!
I am in Virginia , USA

Thx,

I’ll keep it in mind, but I will probably be able to lay my hands on a suitable 3.45 LSD closer by, which would put a smaller offset to my speedo. I’d also like to avoid the hassle of a rebuild.

BR Memo

 

[sfdon]

Bog standard open or bog standard LSD?

 

[Memo]

Bog standard open or bog standard LSD?

Considering the price of LSD and my needs, an open one would be peachy.

 

[BMW3.0CSi]

Have you checked the guys in Bottrop Germany?
KFZ Teile
BMW Oldtimer Parts
An der Knippenburg 108
46238 Bottrop

 

[sfdon]

I have 3 available

 

[Memo]

I have 3 available

Thx. I’ll keep that in mind. I found a 3.45 here in Finland, so I’m going to go with that for now.

 

[Memo]

Well, it turns out I hate the 3.45, so now I am on the market for a 3.25 again. Any offers?

 

[Bwana]

I have one I just removed from my '72 Euro CSi. Bog standard, about 150k miles but was quiet when we removed it. Located in New Mexico U.S.A.

 

[Ed G]

Memo-
Why are you not liking the 3.45? I'm anticipating a change in the other direction (3.25 to a 3.45 with a 5 speed)?

 

[sfdon]

The 3.25 in my car was great if you are on the autobahn.. but I live on an island where the speed limit is 25mph.

 

[rsporsche]

also curious why you didn't like the 3.45. i have attached the speeds / rpm for both the 3.45 + 3.25 with the overdrive 5 speed for comparative discussion. oh, just realized that i used 3.46 for some unknown reason, probably finger splatter ... but that doesn't amount to much difference. i just ran the 3.45 ... so i've attached the pdf

 

[Memo]

Thx for your replies everyone.

I drive the car fairly gently and I'm not happy at all with the higher revs + the considerable speedo error that came with ithe 3.45 driving at 80+km/h. I've been thinking about a getrag 265/6, but that will have to wait untiI find a european one, considering the price + shipping costs.

 

[Rudy3.0CS]

Those charts are great. Seems like a subtle at best difference. The most you see is 5mph difference at nearly 100mph. Can't see how that's worth it. Maybe more noticeable with a 4 speed?

 

[rsporsche]

FYI, the 1st 4 gears of the O/D 5 speed are exactly the same as the 4 gears of the 4 speed ... so all you have to do is to ignore 5th gear.

 

[rsporsche]

Thx for your replies everyone.

I drive the car fairly gently and I'm not happy at all with the higher revs + the considerable speedo error that came with ithe 3.45 driving at 80+km/h. I've been thinking about a getrag 265/6, but that will have to wait untiI find a european one, considering the price + shipping costs.

you know its much cheaper and easier to change the speedo than it is to buy and remove / replace a diff. you can also have the gear changed in your speedo. check out the FAQ - speedometer + odo gear ratios. sounds like you need a speedo with w=0.7125 ... which should be pretty common in Europe ... much more common than a 3.25 diff

Speedometers

The speedometer ratios are as follows (numbers stamped on the speedometer are rounded and include a mm/yy build date):

3.25 KPH W= 0.679
3.25 MPH W= 1.078
3.45 KPH W= 0.7125
3.45 MPH W= 1.14
3.64 MPH W = 1.2164

 

[ScottAndrews]

also curious why you didn't like the 3.45. i have attached the speeds / rpm for both the 3.45 + 3.25 with the overdrive 5 speed for comparative discussion. oh, just realized that i used 3.46 for some unknown reason, probably finger splatter ... but that doesn't amount to much difference. i just ran the 3.45 ... so i've attached the pdf

That's a very nifty calculator!!

 

[starcruiser]

Remanufactured final drive unit, ratio 3.25:1, for 3.0 CSI and 3.0 CSL for all years of production you need 1 for 1 car.

Remanufactured final drive unit, ratio 3.25:1, for 3.0 CSI and 3.0 CSL for all years of production you need 1 for 1 car.

www.wallothnesch.com

 

[rsporsche]

That's a very nifty calculator!!

you can download it from diffsonline.com just do a search on their site for gearing calculator and you will get the spreadsheet. you will have to revise the gear ratios for the tranny that you are using - you can copy the ones i used as they were supplied to me from @Markos a while back.