[font=Arial]My 2005 Mini Cooper S just went in the shop for a few days to have the John Cooper Works kit number 6050 installed and thought I would post some first impressions:

Firstly, the car was no slouch. I took delivery in late September and had about 2200 miles on it after a sensible running-in period. It had been lively and responsive and the close-ratio Getrag gear box made it quick off the mark. The exhaust had also developed a nice rasp and some exquisite burbles on over-run so I had great expectations from the kit.

Mini of Charleston did the conversion and a very clean and professional job they did too. General Manager Brad Davis races Minis in SCCA and his tech did the install. When I collected the car he took a lot of time in explaining the process and took a great deal of pride in the work.

Technically, the kit consist of a new head, new larger supercharger with reduced pulley, cold-air box with conical filter, fuel injectors, spark plugs, new exhaust, new software load and cosmetics. The air filter acts as a secondary input drawing air through a modified firewall box under the windscreen fed by the air vent on the driver’s side (US). There is an electronically activated flap feeding the box that opens around 4500 rpm.

I picked up the car on Saturday and was fortunate enough to be able to attend a Phil Wicks session at the Carolina Motor Sport Circuit in Kershaw, SC. It was a wonderful opportunity to really feel the kit ‘at work’. BTW, Ian from GBMINI.net thanks for the Track Mode DSC mod it worked great!

There is a noticable increase in power, (reported to be between (207/210 BHP) across the whole engine range. At lower rpm it seems to add smoothness. Even the lower ratio 05 took a little time for the engine to get ‘on the cam’ but the JCW smoothed a lot of that out and provided a real ‘urgency’ to the acceleration. Up through the gears, once you hit 4500, it truly sounds as if the kettle is boiling as the larger supercharger ‘winds up’. I know that many performance car manufacturers spend good engineering time on getting the sound just right, well this one sounds right, not to mention the kick in the pants you get from the secondary air intake opening. That, combined with some quite wonderful sounds from the exhaust including the ever-popular burbles, makes for a wholesome experience.

To sum up; it’s a great kit. You may be able to get more gee gees with less cash from after-market, but there is a true feeling of integration in the JCW kit. It feels well matched to the engine and the warranty is there without question.

MW[/font]

 

Been driving mine for about a week now (also after a 1000 mile break in prior to install). I agree with everything you said. I especially noticed the improvement in the first gear range starting off. it is much smoother and the power gomes on much sooner. At 4500 when the secondary air kicks in you can hear the supercharger wind up big time. Sounds like a turbine. The exhaust note is a little deeper than stock "S" unless you push the car then it seems to really growl. The "burble" is more pronounce than the stock system. I would also agree that the installation seems better than earlier models. For one thing the Cooper works badge on the intercooler is not a sticker but a thick (maybe plastic) badge. I would also agree that it is nice to still have factory repair coverage.

 

BTW, no matter what they tell you (or who tells you), the JCW kit DOES NOT come with a larger supercharger! It's the same supercharger but with a smaller pulley.

 

It certainly looked like a different supercharger... interior ports were quite different.

 

I have seen side by side comparisons of the ports and vanes. No doubt there is a difference. Maybe not in actual size but deffinently in output. What those changes are exactly is anyone's guess.

 

The superchargers are identical. Just a smaller pulley.

 

The JCW has the abraided coating to get a better seal at the higher RPM's that the smaller pulley creates (tho not as small as the 15% or 19%).

The coating also helps protect the rotors from the additional heat generated.
The supercharger also has revised gearing for the water pump to bring it back down to design speed.

The ports are also slightly modified.

All this info comes from Mike Cooper.

The 2005 MCS superchargers now also have the coating, but obviously not the 14.8% pulley or reducer water pump gearing.

 

I see you bought what he was selling. Ask anyone who has had them apart, ask any MINI technician (not the salesman), and they will tell you. "They are identical, with the exception of the pulley." If you have doubts still, go to the dealer and watch an install of the JCW.

If you still are under the perception that they are different, great. Their sales and marketing team has succeded. The most important part of selling is achieving the perceived value in the client.

Enjoy.

 

my blower is more different than yours

 

http://www.johncooper.co.uk/JohnCoop...S+Tuning+Kits/


Check out the links at the bottom right. There's a video (JCW kit walk-around, or somesuch) that has a decent shot of the underbelly of the S/C. It should be enough resolution to draw conclusions from.

--Jeff

 

yeah, I think I'd rather have TOO's IC mods over those from JCW. At least it's a known quantity!

jeff

 

Yeah, your blower job is certainly different than everyone's!

I sure wish I knew everything that you have up your sleeve...

 

Bisch,

I Did. Explain why the JCW SC they put on my MINI has a black coating the SC that came off didn't. And why, when I turned the SC the take off for the water pump turned a slower speed than the original one.

I guess your one of those who never really compared the two together, but seem to know alot about them.

 

Easy pal. The explaination is simple. You have an '03. The JCW SC uses the "coated" vanes...as now do all production MCS's ('04 & up). They ALL have the coating now. As far as your rotational observation, you most likely were observing the difference in rotational speed as a result of the pulley size in which you were turning.
BTW, if your theory of gearing were correct, the JCW would have spun the w/p take off at the same speed as original to match the OEM specs.

"MYTH BUSTED"

For what it is worth, this is a very old topic that has been hashed over numerous times before. A search will bring up all the info you should know.

 

It is the same supercharger. Somehow many moons ago, when the JCW kit first came out, there seemed to be some promotional literature that came out stating this (I remember it about 18 or so months ago). Since then pieces of false information that was in this literature continue to show up in press articles and through the dealership network. I know it sounds cool and it would be great if the supercharger were different, but since mid '04 the MCS began carrying the 5th gen Eaton Supercharger. Based on the JCW literature as well as the literature from Eaton, the 5th gen had a different coating, which allowed tighter tolerances between the supercharger blades and the housing. This in turn was suppose to increase boost levels at higher temperatures. This has really never paned out to be true. Technically through the grapevine the supercharger is suppose to last longer (don't know how much longer), ie tolerances will maintain a tighter value, not that the supercharger will break down. But again, this isn't an advantage to the JCW anymore since the MCS has it as well.


I think JCW included the supercharger and pulley to prevent failures to the shaft or bearings due to inexperienced installers or accidents. Many of these techs do not install JCW kits on a regular basis. Remember it took Randy a little time to get this down as well, but now he is a speed demon. Since JCW was under extreme pressure to deliver a kit with 0 defects and had excellent reliability this was probably a safer route. I am unsure how much this adds to the kit price, but it does some (remember the old one is shipped back). The reliability is attested to the fact that a JCW kit has never failed, nor has a single JCW item been returned yet for a warranty error, as of a few months ago based on an interview with Mike Cooper. JCW needed to deliver to maintain a contract with BMW.

 

That is exactly why they change the supercharger. It's actually easier just to change out the supercharger than changing the pulley - if you aren't very experienced in what you are doing.

 

FURIOSO stated that he counted the rotations of the pulley and counted the rotations of the water pump input for both the stock and JCW blower, and they were different. I have no reason to not believe him. It would be very simple at the Eaton manufacturing plant to use one gearset for the standard MCS item and a different one for the JCW item. It really would make sense to do that from an emissions standpoint, so that the JCW's cooling system behaves exactly like the stock one.

That said, I haven't heard of any cases of water pump cavitation or resulting damage from stock blowers and aftermarket pulleys.

 

....but even your blower doesn't have the different color super-duper coating. Just think, you could be at 210 at the crank if ya had the right splooge inside.