[djustice]

I did alternator and powersteering bracket as i Upgrade from the stock alternator that was a "big" case alternator and the bracket would not fit my SI 10/12 style powermaster 150 AMP.
Brackets did fit but it lowered my powersteering pump making the belt rub on the powerstering gear Attached to the frame.
This would eventually whiddle the belt down and ended up with it thrown, after speking to CVF the solution was a new smaller diameter pulley.
I was concerd about preassure buildup due to the pump beeing overdriven, but i was assured that the powersteering pump relief valve would keep pressure in check.
For all it's worth it seems good now , except the alternator fan on the powermaster alternator self Clerenced about 1/16 " off the bracket on intital startup.

[RocktimusPryme]

Originally Posted by torqhead

Just an opinion, not a metallurgist or whatever word you would use, but I think the factory pulleys are stronger and don't wear out as easily. I've seen the aftermarket pulleys with grooves wore in them from possibly too tight belts more often than I have factory pulleys.

I think most of the aftermarket units are aluminum. Machining is probably better today, but they probably are softer metal. For most people who likely dont drive their hot rod more than 1000 miles a year I doubt you would notice. I could see them going south faster if you put a lot of miles on the them.

In my case, I thought the benefit of going with the aftermarket pulleys was to KNOW that they are all made for the same belt size. When you mix and match, aftermarket and swap meet pulleys I see groove mismatches all the time. Even if they do line up correctly. Not to mention I have no idea how many miles are on those original units.

[HWYSTR455]

I have over 150k miles on my set of aluminum Ram Air Resto ones, they still work fine.

You can buy them in a matching set, so there's no question. RARE are very knowledgeable, and list a number of different applications in their' catalog.

https://www.ramairrestoration.com/pontiac.html?cat=16

OE steel ones run the risk of being bent, and you can't always tell by the naked eye. Same with wear, you can't usually tell by looking at them.

The mount holes can also get wobbed out. That can happen when using an A/C single groove and crank 2 groove without the added 4 hole ring-plate on the front side. You can accelerate that 'effect' by switching to a cycling, POA valve replacement valve.

Another thing is that some of the OE crank 2 groove pulleys you can't tell by looking were A/C car pulleys. Those are meant to be stacked on top of the crank single groove A/C pulley. If you omit the A/C single groove crank pulley, instant misalignment.

I've seen a number of people use the OE A/C water pump pulley without the A/C crank single groove pulley or just the A/C crank 2 groove and experience misalignment. (I did at one point run a 4-hole ring-plate spacer behind an A/C crank 2 groove in place of the one groove A/C pulley, which works).

I forget, but it may be that the 2 groove cranks pulleys are pretty much the same, and it's the water pump pulley that changes on an A/C car. But I would think the PS pulley would change too.

Of course if you look up all the part numbers of the pulleys you have, and match them to a model, with or without A/C, you can verify if what you have is a matched set.


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