Dawg, the rear you have has the best ratio..... (archive)

for our cars. The M60 motor did not develop max torque until somewhere around 4500 RPM. To offset this fact, BMW used a 3.15:1 rear end (same as the 740 sport). This gave the motor a higher final drive ratio to the wheels resulting in better low end performance with the lower RPM torque output of the M60 motor. With the introduction of the M62 motor, BMW kept the overall max HP the same (282) but tuned the engine to produce max torque somewhere in the region of 2500-3000 RPM. This gave the M62 better off the line performance, all other things being equal. The ratio of the rear was then changed to a bit lower final drive ratio (not sure on the number but 2.83:1 seems to ring a bell). The idea was to offset the torque gain of the motor with a higher final drive, and give the newer cars 96->>> the same overall performance as the M60 cars.
With the introduction of the 740 sport, the 3.15:1 rear was put back into the car, with the M62 engine. This combo, with a higher stall speed torque converter gave the sport models quite a kick in the pants in relation to off the line performance.

Bottom line, you should already have the higher final drive 3.15:1 rear in your car. You might be able to find a higher ratio somewhere else, but your mileage would suffer.

Regards,

Greg
95' 740i

Hey Big T...look forward to meeting you at the DC meet! I too have a 95 and am interested in finding out more about the rear end. Do you know how difficult it is to replace the rear end so that I can get more torque off the line? I have a buddy with a 98 and I noticed that he somewhat smoked me.

Does it make sense to find a used rear end off a newer model?

David
Salty Dawg

Follow Ups:

Are you sure about this? MikeH 11:51 3/10/2002 (1)
- Checked the TIS.... I'm sure (more) 7SeriesSoon 13:46 3/10/2002 (0)

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