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MINIAC · Jul 23rd, 2003, 09:16 PM

Some food for thought on the pulley choice:

Quote:

Originally posted by RandyBMC

There are two basic types of pulleys. Here are the pros and cons of each:

New taper bore design

Pros:
No heat required for the installation on the supercharger
Capped end prevents installation problems with belt alignment
All stainless steel

Cons:
Heavier than the other style

Interference fit design

Pros:
Lighter weight
Interchangable sizes available (but why you would really need this is up for debate)

Cons:
Heat is required to get the new hub on the shaft - so care has to be taken to cool the hub ASAP to prevent damage to the shaft seal
Alignment is a one shot deal, and there is no stop to prevent the hub from going on too far or not far enough

Testing has been done on both units to determine the torque required to spin on the shaft, and the taper bore actually has a higher torque rating, but both are well above anywhere close to the load on the pulley - the belt would slip way before the pulley would on the shaft.

Interference fit is used in several other applications - including the stock set-up - without slip issues. I would be concerned about the orginal interference pulley that used to be available (no longer on the market) that is all aluminum. This has to do with the different thermal expansion rates of steel and aluminum and may cause issues over time. The new designs all use steel hubs.

Taper bores are used on numerous industrial applications where direct torque loads are carried at sustained RPMs - much more grueling than the application we have in our Eaton M45s.

I think what I'm saying is, they are both good products - I'd be happy to help you make the right decision based on what your needs are.

Let me know if you have any other questions.

Randy
720-841-1002

The Alta pulley is taper fit while the Madness pulley is interference fit. The Alta pulley is about $40 cheaper than the Madness pulley, and sounds like it's "safer" to install.

Jul 23rd, 2003, 09:16 PM	#13
MINIAC MINI Profiler Join Date: Feb 2001 Location: City By The Bay Local Time: 04:30 AM Posts: 8,510 Offline	Some food for thought on the pulley choice: Quote: Originally posted by RandyBMC There are two basic types of pulleys. Here are the pros and cons of each: New taper bore design Pros: No heat required for the installation on the supercharger Capped end prevents installation problems with belt alignment All stainless steel Cons: Heavier than the other style Interference fit design Pros: Lighter weight Interchangable sizes available (but why you would really need this is up for debate) Cons: Heat is required to get the new hub on the shaft - so care has to be taken to cool the hub ASAP to prevent damage to the shaft seal Alignment is a one shot deal, and there is no stop to prevent the hub from going on too far or not far enough Testing has been done on both units to determine the torque required to spin on the shaft, and the taper bore actually has a higher torque rating, but both are well above anywhere close to the load on the pulley - the belt would slip way before the pulley would on the shaft. Interference fit is used in several other applications - including the stock set-up - without slip issues. I would be concerned about the orginal interference pulley that used to be available (no longer on the market) that is all aluminum. This has to do with the different thermal expansion rates of steel and aluminum and may cause issues over time. The new designs all use steel hubs. Taper bores are used on numerous industrial applications where direct torque loads are carried at sustained RPMs - much more grueling than the application we have in our Eaton M45s. I think what I'm saying is, they are both good products - I'd be happy to help you make the right decision based on what your needs are. Let me know if you have any other questions. Randy 720-841-1002 The Alta pulley is taper fit while the Madness pulley is interference fit. The Alta pulley is about $40 cheaper than the Madness pulley, and sounds like it's "safer" to install.