My '06 R52 JCW car is basically all stock, with the exception of the Motegi wheels. I'm not overly impressed with the power this engine puts out compared to my '04 R53. I put a 15% pulley on the R53 a while back, it really woke up that car, other than the one ball mod on the '04, I'm very pleased with the power from that engine.

So I'm thinking of a pulley for the JCW engine, I'm still running the stock 11% pulley, and no other mods are done to this car since I got it back on the road after a year of fixing everything.

I have heard that the 15% pulley on the JCW engine isn't much of a difference between the stock one. I'm thinking about the 17% pulley instead. My questions are as follows:

Will a 17% pulley be too much? It's basically just a street driving car, no track time
Will I need to get a larger intercooler to try and keep the heat down inside the intake?
I'm sure I will need a different belt, and probably a new set of plugs.

Your thoughts and ideas please, I just want a little more power from this JCW engine.

Thanks, Bryan

 

i run a 17 % on my factory jcw track car you you should not generate enough heat to pull timing unless you are pretty fast in the mountains or do multiple back to back pulls

 

Have had -17% SCP since car was new, it now has 234K miles on same engine/upper cylinder head...only swapped out the Supercharger because I got a new 05/06 one from Marren Motorsports in CT for $500.00. They would tear them out of a new MINI during track prep phase when adding new car to the team, then install larger SC/injectors.

I know a boat load of guys who went with the -15%, only to end up doing it all over again for the -17%. In 6th gear with a -17% no need to down shift when on the freeway....just mat it, def noticible on earlier 02' to 04's with the higher trans gearing.

ps; And stay clear of the light weight engine dampers...They're designed for short road tracks and only good for gears 1-4, not good for daily driver. The face lift crank dampers are perfectly good IMO, or go ATI.

Do that and you'll be fine.

 

Since it's a JCW already a really cool option we do all the time is to just add a 2% larger ATI damper. The crank pulleys are so common to fail its like doing maint, but getting a mod as you gain a bit more boost. I actually run this on my GP with the stock JCW pulley.
https://www.waymotorworks.com/super-...ulley-r53.html

Then later if you do want more boost you can upgrade the supercharger pulley to a 15%.
https://www.waymotorworks.com/15-sup...ulley-wmw.html
Or you can go all in now go with the 17% which is a nice bump from the JCW, and do the standard size ATI damper as the maint item.
https://www.waymotorworks.com/17-sup...ulley-wmw.html

I wouldn't be concerned with needing a larger intercooler or that as the internet like to scare people into buying parts. But you will be fine with the stock IC and a 17% pulley, plus you already have the larger injectors so it runs rich as is.

 

The JCW stock SC comes from factory with a -11.5% reduction pulley already attached, the ATI will only put that reduction in the -13.5% range.

I've known both GP and JCW owners who went this route and from what they've said and from my driving the car it felt very anemic in comparison with respect to power and torque....So much so, the JCW owner, while misguided by a well intentioned shop owner in Worcester, ended up so fustrated he sold it for a Subaru WRX....damn shame too as it was a very low mileage well equipped Red JCW as seen in the early MINI Marketing posters.....

I get a sense these reduction crank damper pulleys were mostly popular before a proper tool was designed to remove the smaller JCW pulley from superchargers.

 

Installed a 17% on my 03 JCW. It really does make a significant difference.

I struggled with this same decision myself last year. Glad I went with a smaller pulley. Wouldn't hesitate to do it again. Great for a spirited daily driver

 

For what it's worth,that that stock engine will hold up to a surprising amount of abuse.
I started with a 15% SC pulley and later, when the rubber in my my crank damper failed, I upgraded to a 10% over Fluidamper pulley as well. I don't know if that equates to a total of 25% more boost but it was definitely faster.
I ran it this way for a couple of years until I burned a piston running hard on the highway for a couple of hours straight.
I'm religious about oil changes and maintenance but, being a *******, I had never gotten around to upgrading the injectors or even the tune. I always meant to but the car seemed to run well as it was. That day it was running so hot in that cylinder that it melted the spark plug side electrode completely away and melted through the top piston ring and down into the ones below.
As it was early Easter Sunday morning, I was in the middle of nowhere, and I figured the engine was going to be toast anyway, I was still able to drive the last 2.5 hours home on three cylinders and it would still run at 85-90MPH.
That gave me a reason to pick up a nice used long block with a JCW head but I still need to upgrade the injectors and get a tune.

Borescope view of the cylinder wall and piston

 

17% for street use, 15% for track use. Continuous high-revs with a 17% will overspin/damage your supercharger.

 

I put a 17% pulley on my 03' JCW.....I love it. I wouldn't do it any other way. That being said, I don't track it. I get around 16psi of boost at WOT and 6,000rpms.

 

thanks for the input guys....I'm sure I am going with a 17% pulley...probably won't be until spring...I need to pull the drivetrain and do a transmission swap...will probably do the pulley at that point

Bryan

 

I also have the 11% JCW pulley combined with the 2% ATI and a bigger intercooler and it makes 13psi. Without the bigger intercooler, it made about 14.5 psi. But it isnt all about pressure, keeping your IAT's low is also very important.

Its pretty fast (very relative for everyone), but I will make the transition to lightweight 16" wheels, as the 17" Team Dynamics Monza wheels are quite heavy. I had the 16" Mini R87 wheels when I didnt have the ATi 2% and it felt more nimble.

 

I've had the death rattle from my supercharger recently. Consequently, I removed the supercharger from my R53 to verify the PTO gears are shot. I've got a rebuilt supercharger from Detroit Tuned on the way and I could not resist having them ship to me with the 17% pulley installed.

This replacement supercharger with the pulley will be its first modification. I've got colder plugs ready to install but now I'm reading this thread about the fuel injectors and I'm concerned I'm not done ordering parts.

My car is a daily driver with 157k miles, in very good condition and properly maintained by me its entire life. I might do 1 WOT pull on the freeway onramp every morning to work but otherwise I drive pretty conservatively - although this pulley may summon the demons within. Are the stock fuel injectors sufficient for my current driving habits or is it important for me to upgrade? If upgrade is important, to what? 380cc injectors? Then tune as well?

 

Go ahead and throw the 17% pulley on there, and drive the heck out of it. No need for new injectors, or a new tune.

 

I made the decision and I am very happy that I did. Combined it with NGK BCR8ES plugs and a Gates 6PK1368 belt.