Absolutely
the best water pump ever produced for a BMW car. Stewart Components is the
leading producer of water pumps for NASCAR, Ford and Chevy V-8 domestic racers,
as well as many newer electric OEM applications from BMW and Mercedes. This
unique pump solves many problems associated with the stock design and later
aftermarket evolutions, and introduces impressive performance and durability
features:
- 15%
flow increase
- Twice
as efficient as factory pump
- Stainless
steel impeller
- Silicon
Carbide and Sintered Carbon Graphite Seal
- Rebuildable
The
initial plastic impeller pump design was lightweight and provided adequate flow
for low RPM use, but eventually cracked. Later designs used a heavier metal
impeller that proved to be very hard on the bearings in the unit. Stewart has
used a proprietary impeller that reduces strain on the bearings and seals in
the unit. This means greater life for the bearings. Additionally an oversized
FAG bearing and high quality seal ensure long life.
The
impeller design allows for more fluid to be pumped at any given rpm. At high
RPM it eliminates cavitation of the pump completely which means more cooling
for your car, eliminating completely the elevated temps seen by many on the
track. Racers will be able to further underdrive this pump for even less less
power loss.
Fits
all E36 6 cylinder cars (1992-1999 323, 325, 328, and M3), E46 non-M cars (323,
325, 328, 330), and all Z3 and Z4 models.