In my opinion that vendor announcement has to be one of the most inaccurate collections of text ever posted on this board.

The difference in the rotating mass of the supercharger with an aluminum pulley and a titanium pulley is down in the noise. The rotating mass of this subsystem is dominated by the supercharger shaft, supercharger vanes and the rotating mass of the water pump. There is likely no repeatable measureable difference on a dyno between this pulley and any other of the same diameter.

 

Wrong. With the same energy applied, a lighter pulley will spin faster than a heavier one. How fast would your engine spin a 200 pound pulley? Yes it really is the spin up that is important, and keeping it spinning is only slightly harder because of the weight (we live in the real world, not frictionless-land).

 

For a particular engine RPM, the lighter pulley *can't* spin faster - its angular velocity is solely determined by the ratio between the crank pulley diameter and the supercharger pulley diameter. To suggest that the lighter pulley would spin faster than the heavier pulley would mean that there's some kind of "reverse belt slip" happening.

And as far as the friction goes, the only friction present is between the belt and the pulley (which doesn't depend on pulley weight), and the friction in the other moving parts of the supercharger/water pump assembly, which aren't significantly affected by the weight of the supercharger pulley either, unless you use a pulley that's *so* heavy that it overtaxes the bearing that the supercharger shaft passes through.

 

Your both sort of right, Kapps is closer. The engine will spin them both to the same speed, constant relevent to the rev limiter, therefore the angular velocity of the pulley will be the same, it will simply require more energy to accelerate the pulley to this fixed max speed. This should put it simply: force=mass x acceleration, acceleration= (velocity final-velocity initial)/time. Since velocity initial (idle) and velocity final (red line) do not change, the angular velocity is the same. The angular acceleration, however, does as the pulley is turned with the same "force" but has a larger mass resulting in a slower acceration (or an increase in time). The angular acceleration will be different, just not by much though. The thought behind this mod is to reduce rotational inertia, decreasing the amount of time required to reach redline. You must consider rotational inertia includes: Wheels, brake rotors, driveshafts, transmission, clutch, flywheel, crankshaft, crank pulley, camshaft, alternator, AC, water pump, supercharger rotors, etc. If you think that the mass of a pulley, that is actually heavier than an aluminum one, will make enough difference in your rotational inertia to warrant the price than buy it. I would personally suggest you purchase a flywheel or lightweight wheels to reduce rotational inertia for this price.

-Addison

 

Uhhhh, for a given engine RPM, it took you longer to get there with the heavier spinning mass. Perhaps I should have written spin UP faster, but I did say that given the same energy input, the lighter would spin faster, which is correct.

 

How about a lightened crank pulley? ALTA's drops six pounds of rotational mass. Don't underestimate the impact of dropping weight from a rapidly spinning part.

 

I've heard you can never get anything made out of unobtainium!

Think of a flywheel made out of that stuff!

Methinks I smell a part for those with disposable income. I also predict they will sell about 10 a month!

Matt

 

No. It doesn't matter if the pulley is 200 lbs. It will eventually spin at the same angular velocity as the Aluminum one. The formula for angular velocity is dependent ONLY on the velocity vector, the angle of the vector, and the radius. Mass has nothing to do with how fast the pulley can go. The formula for angular acceleration, on the other hand, does involve mass.

Dropping weight does speed up angular acceleration. The higher the radius of the part, the more profound the effect will be. Lightweight wheels, flywheels, etc, will show a larger improvement due to their large radii.

 

True, but my engineering education came out. There's a world of difference between the terms "spin faster" and "spin UP faster". One describes angular velocity, which is solely determined by the pulley geometry, and the other is determined by the mass of the components.

 

True - but in the case of the lightened crank pulley (or a lightened flywheel, for that matter), not only is the amount of mass reduction much greater, but the center of mass for both the flywheel and the crank pulley is further away from the axis of rotation than with a supercharger pulley, so the results are even more pronounced, even though the supercharger pulley is turning much faster than either the crank pulley or the flywheel.

 

It's amusing to me to see this has become a discussion. I was tempted when I saw the recent announcement, but decided to see if someone else was as interested.

My first thought upon reading the announcement: "Wonder if people realize they can have any one of other pulleys purchased and installed and still come out with a hundred bucks in their pocket."

My second thought upon reading the announcement: "Most people on NAM don't need this one. This is a high competition racing part."

 

Let's see here;

$597.75 Palo Uber Titanium Reduction Pulley, not
-120.00 Helix pulley
--------
$477.75 almost a set of light weight Rota's
=======

Who will go faster for the least money

 

As I said earlier, the SC pulley is driven by a belt, and weight loss here is much less meaningful. And while the crank pulley also has a belt draped around it, it is not driven by the belt... but by the engine's crank itself.

By virtue of the crank pulley being lighter, performance gains are realized, albeit nothing earth-shattering... The SC pulley just goes along for the ride, whether lighter or heavier...

 

Bwahaahaa! That's classic

BTW it looks to be another knock off of JLM's (helix) pulley.

 

Sure does

 

 

i love what's become of this thread.... anyone catch a glimpse of the new ALTA bling pulleys?

https://www.northamericanmotoring.co...ad.php?t=91329

 

sorry for the late reply... the palo uber mini london company has pretty much always been a much talked about company, even from our beginings back in 2002 in london. our approach has always been not to re-manufacture what has already been done, but, to develope product that serves a purpose and something that no-one has done before...i dont think anyone could not agree when viewing uor product line. our uber wing was two years in the developement due to the necessity of the flexible yet rigid material that was required to complete the wing. our light bar is another example of combining the vintage look of the classic with the technology available today, with the bar completely concealed, unlike all other manufacturers, inside the lower dam for incredible visual appeal. the titanium pulley was a concept developed by uber in cornwall, and developed by sir patrick with his munich automotive eingeneer. titanium is extremely expensice and comes in different grades. we use the same grade that is used in the shuttle and sattelites in orbit. why? a variety of reasons, but most fundamentally is the even internal distribution of weight. ie., when you cut open a tree limb, you see the dark aareas of the grain. this is very similar to the unequal weight dispertion which is most apparent in steel and apparent to a lesser degree in aluminum etc. unlike titanium which is almost 100% smooth, and is void of these weight irregularities. the result is not only a diminishment of weight on the supercharger shaft, but as it turns there is no surging of weight imbalance working against the shaft. the final result is a faster rpm achievement and a significantly more functional supercharger. the titanium is over 200 times stronger than steel, and over 100 times stronger than aluminum. thus, its the most expensive pulley you can possibly make, but it also is the most perfect in all regards. the titanium is extremely difficult to work with, and very timely requiring 15 times the labour haours to produce if comparing to an aluminum of steel component. but, it was something we wanted to do, .
i hope this helps, as we have always tried in europe and now in america to produce the highest quality and the most effective components available without regard to how much it costs us to make..we just want to continue to produce the finest product available for your minis.
kind regards, bryce smythson, international managing director, the palo uber london company. 949-725-7983/uk 011-44-7891-177-886

 

There is a lot to be said of this thread, with some great info on the physics of rotation.

Here is my simple worded breakdown:

It will take more power for the motor to spin a heavier pulley - the crank pulley is spinning the other pulleys.

The supercharger pulley has a very small rotational mass, and because the radius is so small, the mass has less effect than on, say, a flywheel.

The supercharger pulley is spun by a belt, instead of a freewheeling object, like a turbine for example, or a wheel. It therefore, as mentioned above, will get to the same RPM as a pulley much heavier.

Titanium is heavier in mass than aluminum, lighter than steel, stronger than both. Steel is stronger than aluminum however, depending on the property under discussion.

We are talking about miniscule weight differences, and I would argue that absolutely no way would such a difference in material show up on the dyno or on the track.

My bottom line is that if the unit can be made of a material with similar expansion properties, uniform weight distribution, and incredibly light weight for the same price as the next material, then do it. In my opinion, steel is still the best compromise of a material for a taper bore pulley. Do as much as you can to reduce the rotational mass of the steel pulley and be happy with the other properties it has - cost, expansion, and strength (not to mention corrosive properties).

Will this pulley cause problems being out of titanium? I'm sure not, so you just have to ask the question if the boutique uniqueness is enough for you to justify the cost.

Hope that helps!
Randy

 

I hear that the giego caveman has gone into the MINI aftermarket parts business and will be rolling out a STONE pulley for 895.00. You can appreciate the labor involved considering the tools used.

This is a perfect example of just because you can doesn't mean you should.

 

That Randy guy knows Nothing....lol.

Thanks for the simple break down.

 

I can't really say anything more then Randy said by any stretch. It seems fairly obvious that this is a marketing gimmic and that there are no real advantages for running this over a different aftermarket pully.

In regards to palo-uber. I don't mean to be a negative nancy and get off topic... but would it hurt so much to spell/grammar check your posts and memo's before you go to the forums with them? "The queens engrish aint that different then ours."

 

The spelling doesnt get me, the poor use of capital letters and punctuation gets me.


I wouldn't buy from a company that looks like their workers didn't pass high school English.

 

1. This statement caught my eye: "thus, its the most expensive pulley you can possibly make"

I'm not sure I believe it. I think a pulley made from any Hastelloy will cost more. Without doubt, Hastelloy X is more than twice the cost of any of the titaniums.

2. This caught my attention also: [We use it because of its] "...even internal distribution of weight."

This matters a lot on large pieces, but doesn't on little hockey puck-like shapes; especially those used as mechanical advantage rollers.

3. OK. One last thing that bugs me. With all the promising information, there are no details about which titanium is used. Examples: 6AL/4V, 6AL/2SN/4ZR/2MO, etc. (Hey, if i missed, then point it out, please)

 

I have taken the plung, mine is on the way! Scott you are more than welcome to come over and help or even go for a drive !