I'm on my fourth MINI, but it's my first R53. Is the supercharger on the JCW cars the same as on the S, just with a different pulley?

 

The 05/06 superchargers came with teflon coated blades, prior to that no coatings. The difference between the JCW and the S is that the JCW pulley is about 11% (some will say 12%) smaller.

 

if/when you decide to remove the pulley (11.4%) there are JCW sized pulley tools that can do the job. They can be rented or purchased at places like Detroit tuned's site

Whatever you do, do NOT do this:
http://www.facebook.com/r53Mini/phot...399598/?type=3

 

Yes on your car the only difference in the size of the pulley. It does take a special puller to remove it.
https://www.waymotorworks.com/john-c...uller-r53.html

But if you are looking for a little more boost going with our 2% larger ATI damper is a great way of doing it. As you get that little bit more and you also replace the stock pulley that at some point is going to fail. We also found the A/C to work better at stop lights and sitting still since the compressor spins a hair faster. This is what I have on my R53 GP.
https://www.waymotorworks.com/super-...ulley-r53.html

 

Please add this to my shopping list!

 

Question for WMW -

With the JCW blower pulley, what's the new average psi, say at 4000rpm ?
Forgive me if I sound a little lacking here, I'm new at the Mini Cooper game, but is the "system" (lower end, head gasket, etc.) up to the task of the additional pressure on long distance freeway trips at higher mph (80/85 for 65 to 75 miles at a time) ?

Mike

 

I have a friend with a 17% and he has had no issues with gaskets or any other engine problems from the increased boost. The Tritec engine has a cast iron block and has proven itself over and over through time.

On the boost, it is only when you step on the gas accelerating that the BPV activates sending the boosted flow into the engine. At cruising speeds the valve is putting non boosted flow into the engine.

 

You sure? I thought on pre-factory JCW's the actual supercharger was different too (i.e. a 2004 JCW has a teflon coated supercharger, a 2004 S does not), so on his car there would be two differences, the supercharger itself, and the pulley

 

Any model year Cooper S with a JCW Tuning Kit or any Cooper S built July 2004 onward with have a supercharger with teflon coated rotors. The supercharger in a JCW Kit has a 11% reduction pulley.

 

I looked at an article the other day and it mentioned the 03' JCW had ceramic coated impellers.

It's a straight bolt-on, entailing a reprogrammed engine-control chip, a revised cylinder head, a new supercharger, a smaller supercharger drive pulley, and an upgraded exhaust system designed to reduce back pressure.
The bulk of the development time on the S program was devoted to machine work on the cylinder head, aimed at improving intake and exhaust flow. No changes were made to the valvetrain, compression ratio, or crankshaft. The vanes of the new Eaton supercharger are coated with a ceramic compound that provides better sealing, and maximum boost has been bumped from 11.6 to 14.0 psi. Although the system generates more heat than the stock setup, JCW and BMW are confident the Mini's intercoolers and cooling system can handle it without a problem. Similarly, the development team feels the stock clutch and six-speed manual gearbox can deal with the extra thrust.

Found here https://www.caranddriver.com/reviews...t-drive-review

 

Black Forest -

Mmmm, coming from an American car, hot rod/mostly drag racing background. I seriously doubt (could be wrong !?), that the supercharger rotors are ceramic coated.
The ceramic is a VERY hard coating. Even though it is very hard, it can and will chip when flexed. Having a very hard piece of ceramic bouncing around inside the blower, then the combustion chambers would be a VERY bad thing.
Plus, as the case flexes and the rotors flex, the ceramic WILL tear things up horribly. NOT a good thing.

On the other hand, Teflon is a fairly soft material. Not likely to chip, but could flake. A piece of Teflon floating around in all the moving parts is not likely to do any damage at all being that it is a soft material, and that will burn.
Drag racers have been using Teflon striped rotors in all forms of drag racing since the mid/early 70's. Even if a big chunk of strip comes out (from a full sized blower, e.g. 8-71, 10-71, etc.), little overall damage happens.
Even a small chunk of ceramic comes loose, big damage could result.

All that said, I seriously doubt the BMW/Mini Cooper engineers would use a material like that in a supercharger.

Mike

 

The JCW supercharger, is said to give 15.5 LBS of boost (due to teflon coating of the blades.
Of course and 17% pulley will usually do the anyway!)

 

I agree. I could only imagine how much is going on in there at an engine speed of 6500-7000rpm. I remember quite a while ago talking to a Mini tech and he did mention the JCW did have a different supercharger than the S and when I asked if that was related to it just having the pulley and he mentioned it was more than that. That conversation was a long time ago. I always thought it was the early JCW that started with the teflon coated impellers. Perhaps teflon is what Car and Driver calls "ceramic coating"

 

There was kid in our town that liked to borrow boat motors. His father was a DuPont chemist that was to have worked on the Teflon formula.

 

2002-2004 MCS Standard Supercharger
2002-2006 MCS JCW PTFE Variant (Teflon) coated rotors in Supercharger / 11.7% pulley
2005-2006 MCS PTFE Variant (Teflon) coated rotors in Supercharger / standard pulley

 

Yes it is! Day in and day out!