Supercharger and pulley bearings
I pulled this out of another thread so it is more easily found. Let me know if there are any errors.
Karmann SC pulley bearing.
32mm(ID) x 47mm(OD) x 18mm(thick).
Nachi #32BG04S3G-2DL available at bearingsdirect.com for $23.59.
or
NSK#32BD4718DUK available at Bearing Sourcefor $21.70
OEM SC pulley bearing.
32mm(ID) x 55mm(OD) x 23mm(thick).
NSK #32BD45DU or 32BD45DUM, available at BearingSource for $15.40
or
Nachi #32BG05S1- 2DST
Available at bearingsdirect.com for $20.49 and
at $28.53
These are double row, angular contact ball bearings grease filled for auto air conditioners.
Idler and tensioner pulley bearings.
47mm(OD) x 17mm(ID) x 14mm(thick)
Good for 15,000 rpm.
#6303DU or #6303DDU
Available at Amazon
Or
For #63032RS or 6303ZZ try bearingsdirect.com
PSK and SC Idler bearings
40mm(OD) x 17mm(ID) x 12mm(thick)
are from the 6203 series. (Check this info)
Better bearings are from the SKF range. SKF 6303-2RSL and SKF 6303-2Z, good for 17,000rpm, these bearings are sealed on both sides.
The highest RPM rated bearings (22,000rpm) are sealed on one side, SKF 6303-Z or SKF 6303-RSL if you can find them. If a bearing is sealed on one side only it is easy to clean it and repack with a suitable grease at regular intervals to get extra life out of it, the grease gets thrown out during operation. Put the seal towards the front of the car and hope that not too much crap gets around the back. Using double sealed bearings is best.
These are all single row, deep groove ball bearings, grease filled.
Bearings are limited by the speed that the seal can withstand. An unsealed bearing (6303) can do 22,000rpm and the fastest sealed bearing have non contact seals.
The rpm limit is reduced as the load goes up.
Last edited by onehundred80; Jan 20, 2015 at 10:37 AM.