Out of curiousity,

Did you guys use the 5% alternator along with the 2% crank pulley?

 

If you have put 75,000 miles or more on your car with a lightened pulley then feel free to post. If not, at this point it is only a guess as to what the long term effects will be.

Another alternative is to use a newer MINI pulley (if you have a pre '05). They are, if I remember correctly, about 2 pounds lighter than the older models.

 

I also just went out to the garage to look at the old OEM pulley I pulled off (actually Webb did it for me), and it is made of solid steel. No rubber whatsoever.

BTW, when Randy installed my pulley I asked him about the "controvery" about these crank pulleys and he was quite strong in his position that they are safe and the risks are totally overblown (ie, non-existent). For what it's worth ...

 

I did, I installed the Alta-nator pulley when I installed the 2% crank pulley from M7.
I have heard and but don't know from experience that alternators and water pumps don't hold well to over-revving - the kind of stuff that will obviously happen in much greater degree when adding a smaller crankshaft pulley.

Years ago there was a similar product available for Volkswagen engines, though the Volks engine did not have a harmonic balancer lie the Mini, the smaller crankshaft pulley would increase the revolutions of the alternator/cooling fan as well as lighten up the revolving mass of the crankshaft. That in combination with a lightened flywheel was quite a engine waker-upper (proper wording?).

My mini was transformed by the 2% CP and it was reassuring to know the alternator was not being over revved at the same time. BTW - the alternator pulley is quite a bit heavier than the Alta-nator pulley as well - probably even more of a performancve boost because of saved rotating mass I figure.

Listen to those of us that have put some miles on ours - like mine there have been no problems.

Now - go out and have some fun with what the Lord has given you -like MSFITOY said! (Well maybe not in those exact words)

 

Would the JCW belt fit a 16% SC pulley + 2% crank pulley + 5% alternator pulley?! hahahaa (I'm getting so tempted!)

How could you tell if your belt is slipping? Does it sound like the brake's screeching?

 

All stock MCS pulleys definitely have an elastomeric damping ring around the hub - about 1/2" thick. It may be hard to tell once it gets dirty, but all versions are damped.

I quick search on this topic will reveal a lot of heated discussion on the topic (particularly heated by the vendors who want to sell you one) but IMHO one would be foolish indeed to put a non-damped pulley on a Mini not intended solely for the track.

It's just not worth the risk, and no vendor of Mini parts does the sort of mechanical analysis or extended testing that BMW did when they decided to use a damped pulley. You will find members who have had major engine problems after installing an undamped pulley, although whether the pulley caused the problems we will never know...

 

I don't think that is completely true. If sca's mcs is a 2002 it may have the same pulley as the cooper. I have a factory picture of an mc and mcs engine with the same crank pulley on. I haven't seen the mc pulley up close, but it looks as if there is no rubber or maybe a 1/4" thick band of rubber. Either way It looks lighter and less flexible than my 03' mcs pulley. Which looks to have a 1"+ band of rubber in it. This picture and a description of the belt tensioner shock as a "engine pulse dampener" makes me think that this mod is ok.

Also, there has been only one car that had the engine fail, that also had a puylley (that I could find). I know a few people have said that they felt a vibration from the pulley, but as far as I know, the negative vibrations that cause damage wouldn't be felt by the driver if they did exist anyway.

 

I changed my belt when I changed my cranshaft pulley because it just makes sense to, it is about an additional $30 from your local NAPA dealer - and yes too large a belt and it sounds like a screech owl on acid underneath your hood - and yes it happened to me (the belt thing not the screech owl - that would get Al Gore all upset).

 

Will any amount of anecdotal evidence lead you to the conclusion that this is a smart/safe thing to do? If two...six...twelve posters chimed in with reports of 100,000 trouble-free miles would your mind be put totally at ease? The conscious removal of a part intended to enhance and prolong the engine's durability requires a bit more of an I-like-to-live-dangerously personality than I have. It seems that a better (but more expensive) way to shed rotating mass would be via an aluminum flywheel and/or balancing and lightening of internal components.

 

How else are you going to get durability data short of a tear down? And while I agree that the "safer" method of shedding weight involves things like a lightened flywheel and internals, there is also a cost/benefit factor. A lightened crank pulley costs around $150 and has a one hour install. A lightened flywheel costs upwards of $350 and requires the removal of the transmission. I don't even want to think about lightening the engine internals. Obviously, BMW thought the original balancer was overkill when they lightened it for the 05 model. For those of us on the fence, it helps to get feedback from the NAM community. Personally, I'm leaning towards replacing my 04 pulley with the 05 just to be on the safe side. But then again, I intend on keeping my car for 150k miles or so...

 

The larger radius of the fly wheel will make the relative benefit of the lightening the greatest for the flywheel, then the crank pulley, then the alternator pulley.

But, the crank and alternator pulleys take a lot less effort to swap!

Matt