LSD.... A mind/body experience

As you know I've had a LSD fitted last week. Today I gave it the first proper run out with a 160 mile round trip, vaguely justified as a delivery of some of my products.

Up until today I've pretty much viewed the 8 as a lazy driver... a bit like a hungover athlete I guess in that the performance is there, but you have to shake them, slap them in the face etc to wake them up. Today however has changed my view completely. I simply cannot believe that something can change the character of a car so completely in the way that this upgrade has.

It seems now that the stock setup cruises around @ 1000rpms below the band where the real power lies. Yes you can move the gear lever over to S Mode to keep the revs up, but this still doesnt come close to the experience the LSD gives, even in D Mode.

Gear changes are purposeful, and can now give you a hefty thump in the lower back on kickdown. I've driven Urban (slowly), 'A' Roads and Country Bs and about 60 miles on M6. Every single mile was a pleasure.

You know the 'lull' when overtaking a 40 footer, and the aprehension of will it make it..? Well that's gone. You know the sound a stock exhaust makes @ 100mph, thats there at 80mph now. Press the noisey pedal a 50mph in 3rd and you are catapulted forward with no lag. Even at 70mph+ the pedal only needs a quick jab and a storm is unleashed, again with no discernable lag time.

Amazing.

Trade off. Fuel.

2500rpm @ 70mph.
4000rpm @ 100mph

around town and below 40mph no noticeable difference in cruising rpms as the 5th gear is simply used earlier. Also the upshifts happen quicker since you reach your desired speed faster.

I've done the exact same trip before and only averaged at best 27.5mpg. Today I did the same run and got 23.1mpg. Significant difference I will accept. BUT I think I get my money's worth, plus interest

it is an 1993 e34 M5 LSD, ratio 3.91. Quite a hike in gearing but it has made a real difference. Everything is so responsive to the throttle I still can't quite believe it !!

Cost 250 quid plus 4 hours fitting. Buy one

Cant remember where I read it but I was under the impression my old diff was 3.14 or something as I have a 1997 840 Sport. Could be wrong though.

I also noted that most conversions talk about 3.64 being used. Probably less silly experience and a good compromise.

All I can say from the last couple of days is that the car's character is 100% different now. It feels poised and, to be honest, actually feels pretty fast ! D Mode is better than previous S Mode, and S Manual is hilarious And it's all so effortless to boot.

Had to change the Backplate, Front Mount, input and output flanges (simply swap it all from the M5 one) and drain and fill will fresh BMW LSD oil. Took 4 hours as to gain proper access on the vehicle lift they (mechanics, not me) had to remove the exhaust. Other than that it was a straightforward job I'm told.

I am lucky in this area as the brother of the main BMW dealership has set up his own specialist Garage, so you get best of both worlds - reasonable labour costs with the backup of Dealership Knowledge/data.

Ok, done 350 miles since Monday morning and a bit more 'research'

30mph = 1400rpm
50mph = 2000rpm
70mph = 2700rpm
80mph = 3000rpm
90mph = 3500rpm
100mph = 4100rpm

0 - 60 = approx 6 secs in S Manual. I set off in 2nd to minimise gear change times. Fairly respectable for a 2 ton car.

Fuel @ constant 75mph = 25mpg (flat road). Was previously 29/30mpg.

I havent managed to spin it round 180 degrees at a junction yet, and I doubt it ever would unless I turn the ASC off - the light flickers if I press too hard on the pedal at junctions so I guess it's doing it's job. Still dont like the way it bleeds all the power away though, it seems a bit of a basic system to me.

Zitat von Noggie

I usually turn the ASC off unless the road is wet.

Ah yes, but when you have spent as long as me trying to get rid of the damn ASC light from my dash you will appreciate that I don't really want to look at it any more than I need to