I cleared my mind of everything I knew, or thought I knew about
E36 steering racks and studied the thread
http://forums.bimmerforums.com/forum/showthread.php?t=1370008&highlight=steering+rack. I then edited and condensed what I thought was the best information devoid of rumor or subjectiveness (If anyone has any specs for the E46 racks I'd like that info). It's not really as confusing as the internet makes it out to be.:p
Non-M Z3mm/rev on center:
53.5mmrack type:
on-center ratio:
ratio @ lock:
mean ratio:
rack length: 144.5mm
turns lock to lock:
2.71996+M3/E36mm/rev on center:
45.5mmrack type: progressive
on-center ratio:
ratio @ lock: 15.4:1
mean ratio: 15.6:1
rack length: 145.6mm
turns lock to lock:
3.21995 M3:
mm/rev on center:
39.0mmrack type: progressive
on-center ratio: 19.8:1
ratio @ lock: 15.4:1
mean ratio: 17.6:1
rack length: 117mm
turns lock to lock:
3.0Rack Ratio is a calculation of how many degrees the front wheels turn per (1) 360 degree turn of the steering wheel. Steering Rack Ratios are application-specific, and dependent upon the geometry of the spindle they are attached to. Since the interface between the spindle pivot point and tie rod attachment point create the geometry of a lever, two identical racks installed into two differing chassis may result in differing ratios, as the lever geometry resulting from the spindles in each chassis may be different.
The most accurate way to compare rack performance is the on-center mm/rev spec. Simply put, this is the linear translation in millimeters per (1) 360 degree rotation of the pinion gear from center (defines initial rack quickness). Overall rack gear length determines the lock to lock range and comparative turning radius potential.
Basically there is a simple rule that ALL E36 racks (including Z3 and ti) are the same with only TWO exceptions.1-1995 M3 is slower (less mm per pinion revolution)
2-Any Z3 (besides M models) is faster (more mm per revolution)
