Thursday, April 27, 2017

mini love - part 2

I have been spending quite a bit of time researching and planning for this (hopefully one time) modification of both the drivetrain and suspension on my R53 MINI Cooper S.

In mid April we have a few weeks there were not so wet weathers. I have been hoping for a relatively dry spring to begin implementing the performance upgrades modifications to the Mini. I would be doing these very extensive work in the driveway exposed to the elements. Starting last week the weather has progressive gotten wetter by the day. Today is just plain depressing with continuous rain.

I created a spread sheet to manage the parts that I need to procure for the performance upgrade. I spent some time shopping for the Quaife LSD. The price in the US ranges from just under $1000 to $1300. I then found out I can save considerably by ordering from UK. I sent 2 email inquiries not being optimistic about the vendors respond. To my surprise both responded promptly and professionally. I ordered from the first responded and were extremely impressed with their professionalism. I was a bit concern with overseas shipping of something this dense. I put in the order on Thursday, and it arrived at my front door the following Monday via DHL. I am impressed.

Bit by bit the parts begin to arrive and I need a staging place to keep all of them. I have been reviewing all the available sway bars for the rear, and I narrowed down to two brands and three bar diameters. Using the stock 17.2mm as reference I decided that 18mm would be too weak, 20mm may be a good conservative choice, and 22mm may be too stiff. I say stiff to mean torsional stiffness. Knowing the Mini, like most FWD cars, the car companies tend to set the cars with heavy understeer bias, I decided to go with 22mm bar. I measured the stock front sway bar and it is 14.5mm 24.23mm which I do not plan to change.

I have been planning in my head as how to approach the clutch, LSD, and the supercharger pulley installation. There are two alternative approaches. One is to only remove the manual transmission together with the bell housing, and the other is to remove the entire engine drivetrain as a complete unit. On the surface it may seem removing only the manual transmission is easier. The facts is both approach requires very comparable amount of work. The former requires the complete removal of the front subframe which affects the front suspension and drivelines, in addition to having to at least loosen one or both engine mounts. The latter approach seems on the surface more involving, but is the approach I am leaning towards. It requires less struggle under the car and once the engine is removed, changing the supercharger pulley, separating the transmission from the engine is so much easier.

With patience and a lot of due diligence the parts slowly begin to arrive. As I would be performing this rather labor intensive modifications on the driveway failure in the logistics is not an option. Any unexpected complication would mean the MINI would be sitting on the driveway under the assault of the elements - something that I would want to avoid the best I can.

Swift suspension springs

Quaife limited slip differential

it arrived from UK 2 business days from my order - I am very impressed with the Brits and they are extremely pleasant to deal with and you can bargain with them as long as you are reasonable

I went to the Alta showroom to purchase a 22mm rear swaybar as I like their design

while there I stopped by a tuner nearby and saw this Nissan Skyline that was brought in from Japan and heavily modified - it just sold for $100,000, I was told

a set of Koni Sports (yellow) struts and dampers arrived

the AC Delco brand of engine belt tensioner is identical to the "genuine" MINI except it costs 1/2 the price and has the MINI or BMW stamping grounded out; note it is Made in Germany

the special belt tensioner tools and shorter micro-v belt for the 15% reduction supercharger pulley installation

some of the smaller parts and tools for this project

I chose this affordable single-mass clutch conversion kit to replace the factory dual-mass clutch; my clutch is totally serviceable but because of the extreme labor-intensive steps to install the LSD any sane person would replace the clutch and flywheel even though they are in perfect working order

this has the most detail illustration of the clutch kit but it may just be a generic kit

inside the big box that contains the single-mass flywheel and the small box that contain the pressure plate and the friction disc

the clutch release bearing in the kit is smashed because of the poor packaging - the plastic tab was damaged by the 20 lb flywheel in transit

the pressure plate and friction disc are both made in Japan; Osaka seems to has a concentration of industries of mechanical sorts

the friction disc is of high quality and the friction liner has metallic particles strands (metallic liner is often the cause of unfounded complaints of brake dust) and I prefer these semi-metallic liners

note it is made in Japan; when I was considering ordering this kit, one of my utmost concerns was the quality of the friction disc; seeing this now first hand I am very pleased with the quality

below this is the clutch pressure plate

it too is made in Japan

the outer diameter of the mating surface of the pressure disc and the friction disc is about 8.5 inches

the flywheel is not made in Japan - totally understandable; it is likely made in China or other Southeast Asia country where labor rate is low

the quality appears to be good

I did a lot of research before choosing Exedy clutch kit. There are not much report of use experience on MINI forums. This clutch set is considerably lighter than the factory clutch. The flywheel weights in at 19 lb 6 oz and the pressure plate and friction disc are 12 lb 6 oz together. The entire system is 31 lb 12 oz, compared to the reported 40 lb of the factory system.


  1. Is there any supercharger service you can do? I heard they have their own oil system and over time loss of oil leads to failure.

  2. Hi Rob. I considered it and did a lot of reading on NAM. I would check and add oil if it does not requires messing with the water pump. I infer the oil only get depleted at very high mileage. Mine is at 42k. I might change my mind once the engine is pulled. I forgot if your circa 03 is a MCS. All I remember is it is chilli red.

  3. It's 06 with oem posi. Have you run the 1/4 mile at pir or Woodburn? I thought I had low miles at 50,000.

    Have you run 1/4 mile at pir or Woodburn?

    1. You are fortunate to have factory LSD. It cost $1000 labor to put in. I don't drive that much as for years I did a lot of work from home. I also very good in planning my shopping trips. It is my daily driver, but more often weekly driver. I met with Alex at 503 Motoring to swap drive our MCSs. His have quite a bit of mods. He happen to mention 1/4 mile at PIR, which I have not done. I have since read a few more threads on SC oil change and the wise words is leave it alone especially with our low mileage. I have observed Pelican Parts behaviors on many different forums. Let's me just say it is not a place I likely to get parts from.