Preliminary report: 1. Keep in mind I am fairly novice, comfortable in B (intermediate) group with HOD. 2. I have run the 2013 MCS 3 times previously at Thunderhill and once at Mazda Laguna Seca., 3. The only relevant mods on the cars are a JCW RSB (19.5mm) on the R56 and a 22mm solid NM Engineering RSB on the 2016 JCW, and 4. First time to track the JCW.
So, observations: 1. The myth that BMW ruined Mini go-cart handling with the F-56 is just that, a myth. The car points and goes with the same solid responsiveness of the R56. The ride feels quite different; the F56 "feels" "more refined", the R 56 feels more like a "classic" sports cars. I have Dynamic Damper Control on the F56 and ran in "Sport" mode. While the DDD shock/spring stiffness is less than the F56 JCW with the standard "Sport Suspension", it is at least as stiff as the R56 and plenty for my driving level and beyond.2. The increased horsepower of the JCW made a huge difference into and on the straights - with cornering advantages, right there with a fair number of high horsepower cars. 3. Despite the horsepower and apparently equivalent handling, the R56 seemed to perform better (overall smoother handling, seemed to track better and competed better against the big dogs.) Took me a few sessions to figure out what was up, then it hit me - the OEM tires on the F56, Hankook runflats, suck and were noisy and squirrelly on hard corners. Caused me to back off as it seemed the car was about to lose it. The Michelin Pilot Sports on the R56 made a huge difference; never would have thought.
Conclusion: the F56 retains the Mini spirit. Sure, I miss the speedo and am still getting used to the body style changes, but still a Mini and still a blast. That having been said, the R56 remains a hoot and still reigns as the family go to track car, but only because we've made the F56 the "daily driver" and will be investing in additional mods for the R56. Love 'em both.

 

Great write up. It will be interesting for you to drive the F56 with a set of pilot super sport tires. I had a set on all my last 3 MINI's. 2010 R56, 2014 MCS and now 2016 JCW. I have not tracked any of these cars but do find that with sticky tires that sometimes wish I had not purchased the DDC on the JCW. I have a similar set up to you with a 22mm RSB. Then again I am thankful during city driving for the softer suspension on the 18" rims. Those tires as you know do not handle put holes well.

 

After driving my friend's F56 MCS and my JCW Coupe with the sport suspension I can see why many Mini owners prefer the F56's ride, no matter what tires they have. My friend is a female, and she simply doesn't have any interest in driving the twisties, etc. I suggested a rear sway bar and she said "I just don't drive it like that". I think Mini went after the female driver (like her), who is attracted to the body style and more deluxe interior and doesn't want to feel the bumps. The DDD option is great too. She has the standard suspension and it rides great. A little too much body lean for me, but just right for her DD.

 

I'd be surprised if anyone is driving anywhere near a level where they need any sort of suspension mods. RSB will change your feel, but the stock suspension setup is well beyond the capabilities of even PSS. I don't think it has anything to do with 'female driver' or any other such nonsense. The body lean isn't going to be a bad thing, and it'll handle bumps/etc with more stability that way. Weight transfer can be as important as lateral flatness. You end up driving laps around people with thousands in unnecessary suspension bits who added them because it 'feels stiff' instead of adding them because of lap times.

OP you're spot on though, runflats are extremely heavy tires and put a ton of weight on the corners you don't want/need. To do a back to back, you've got to do similar tires in similar weather. If you found the F56 better as it was, it will probably be lightyears ahead with equivalent tires.

 

How come RFs are heavier, the stiff sidewall? How much more do they weigh?

 

RFs are a lot heavier because they have a cell structure which is what allows them to hold together without pressure. Some of them are up to twice as heavy as their non-RF equivalents, depending on how robust they are. The argument is that you have say a 35lb tire instead of a 25lb tire, but you can drop your spare wheel+tire for 'every day', which saves you say 20lb wheel + 25lb tire. Net weight they claim you save 5lbs, gaining 10lb per corner but dropping 45lb in the trunk.

Problem comes in when you start to assess where that weight is - adding 10lb, or over 20% to the unsprung mass is huge at the corners, and on a track you're going to pull that spare out and leave it in the service paddock anyhow.

 

I keep hearing about the "unsprung weight" saved with lighter wheels/tires helps you cornering. How does it do that without improving the grip and/or chassis dynamics? Is it just easier to turn the front wheels into the turn (turnin)? I'm not sure I understand the physics of that.

 

By reducing the unsprung weight you improve acceleration and deceleration, and help the suspension to work better.

 

Unsprung weight is the weight that is moved by the shocks and springs. It the weight is less it means that they can react quicker and are less stressed. In practice the tires will stay in contact with the road better....this is true especially when there are imperfections. If you shave off 3lbs per corner of the car you can notice the difference.

 

This is a good thread and very useful. I had an R 56 JCW that I loved and it was a different beast with the Michelin Pilot Sport A/S 3s V the original Dunlop runflats and I made the switch with my current F56 JCW as well to the Michelin Pilot Sport A/S 3+. I did not go with the Pilot Super Sports simply because I do not track the car often although I do a substantial amount of twisties at speed on a normal basis. The difference in handling is very noticeable and the increased comfort of the ride and reduction of road noise is as well. I also noticed a significant increase in stability in handling with the F56 over the R56 at speeds above 110-115 mph. The increase in torque with the F is also very significant. It is a better performing car although I prefer the appearance of the R.

 

I see some transplant B48 Engines in R56's in the future!

 

Hey OP I think I talked to you at that track day. (5/6) Did you take any video of your laps?