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Jehu
10-15-2006, 09:01 PM
So if i remember correctly, this (http://cgi.ebay.com/ebaymotors/BMW-E34-M5-3-73-Limited-Slip-Differential_W0QQcmdZViewItemQQcategoryZ33731QQihZ 011QQitemZ320038353519QQrdZ1QQtcZphoto)would work superbly in my 540 6sp to give me quicker acceleration in higher gears meaning i wouldn't need to downshift to giddyup when in sixth gear,right?

Paul in NZ
10-16-2006, 12:37 AM
The whole idea is sixth is an overdrive...and from my experience even in sixth the 540 has good acceleration.I love the sixth to 3rd move...thats serious!
The large case makes it ideal for the 540 though.It makes it less suitable for other E34's so thats good for you!

Jehu
10-16-2006, 01:00 AM
Maybe i need new spark plugs in additon to the RedLine injector/valve cleaner i've been adding to the gas and the new fuel filters and the new air filter and the new oil and oil filter. I wouldn't yet say my sixth gear acceleration is 'fast' at least not when i'm say just at 65 MPH for afew moments. If i've been cruising in 6th and it has momentum built up then ya it isn't sluggish, its not like out of 3rd but with momentum its better. I am still only four moths into driving a manual tranny after a lifetime of automatics so as the opportuinities continue for high gear acceleration pep i could find the right method but if this diff would give me 3rd gear jump while in 5th it'd be worth it... now if i could just figure out how to get my self a new chip...

Paul in NZ
10-16-2006, 01:04 AM
its not fast but in sixth its still useful.
First rule of driving....momentum rules.

632 Regal
10-16-2006, 09:56 AM
should fit without any issues, nice gear ratio too. with overdrive it shouldnt be too much either.

zman-95-540i
10-16-2006, 10:50 AM
Interesting... how many hours should I expect to swap out the diff. Also, any idea what a reasonable price would be for the diff being auctioned?

BillionPa
10-19-2006, 01:33 PM
i wouldnt go over 3.25, unless your engine is producing like, no power.

Jehu
10-19-2006, 04:25 PM
Are you saying with the strong M60 V8 i'd just be poppin' wheelies all day?

BillionPa
10-19-2006, 11:27 PM
there is a fine line between optimal and suboptimal, you would have a 33% increase in RPMS at any given speed in the same gear, quite a bit more gear shifting, and the car would just feel off.

BMW gave it its stock gearing for good fuel economy at highway speeds, and it only takes a small increase to get optimal torque curve matching.

3.25 is the suggested optimal peformance ratio for a stock or slightly modified engine giving production power numbers.

thats vs the 2.81 that the 6 speed came with, a 15% increase

if you have an engine modified for more horsepower, but not necessarily more low end torque, then 3.25 is still the suggested ratio. if you have crap loads of torque, then 2.81 is a great ratio (as long as its LSD)




.... in conclusion, if your car is making about as much torque as a 530, then the 3.73 is a good buy, if your car has the amount of power its supposed to (i sure hope it does!) then you will hate yourself for getting it.