E30 Zone

Ive got a 320i with a 325i engine, gearbox has not been changed...although not 100% sure as i brought the car already with the 325i engine.
I found a lsd from a 320se 89 (same year as mine) and also another lsd which is 3.46 from an 86 m5 e28.

Which would be best out of both if any.....if neither which sould i look for?

Thanks

i'm sure the 325 came with a 3.64, mine did, ive changed mine with a 3.91, i know others have done the same.

I think auto is a 3.64, manual is a 3.91 and a 320 is a 4.10, so it will be a little rev happy and might annoy sat at 80mph?

Not sure about the e28 lsd.

64 is for the early high comp engine that has little extra and can strech it's legs a bit more so try it out and if you take to long going through the gears then stick with the 91.

higher number ratio will be quicker accelerating but have lower top end. depends if you want quick accelerationor quick top end? id expect the 3.46 to be a lower ratio than the other unspecified diff as that is more likely to be a 3.64 or above.

fuzzy wrote:higher number ratio will be quicker accelerating but have lower top end. depends if you want quick accelerationor quick top end? id expect the 3.46 to be a lower ratio than the other unspecified diff as that is more likely to be a 3.64 or above.

hmmm well i would rather quicker acceleration...not fussed about going 150mph!!

Look at it another way, do you want to be continually changing gears round town??

A 3.64 lsd in a non sport 325i will give the same feel as a sport 325i, as the gear ratios are different, putting a 4.1 diff in a non sport means you will only get to about 49mph in 2nd before needing to change gear, a sport gets to 56 mph.
If you put a 3.64 lsd into a non sport you get to 56.6 mph in 2nd, so pretty much the same as a sport.

Sat cruising at 80mph you will have 4300rpm with a 4.1 diff and only 3700rpm with a 3.64 diff. This is the difference between 28mpg and 34mpg in my car, so another thing to consider, if it is an everyday car.

I would guess that a 4.1 diff would feel more brutal but not sure if it would be the one to live with daily.

Anyone tried both?

To the OP, I'm pretty sure the E28 M5 diff is a large case (rather than the small/medium cases) used in the E30

Andy

Thanks for that gizze....i dont want to be changing gears every two seconds!! I tink i will have to go with the 3.64 then.

Cheers Gizze, was searching for some Diff advice last month and decided a 3.64 would be the best compromise for my 325i SE daily driver. Some good points there.

Just need to locate a good condition one though... Although, there's always a brand new Quaife!