I have no idea what my "exact" measured drop is but you can take a look at the photos in my garage. I just set it to the level I like the looks of and then go and have my local Porsche race shop do a full corner balance alignment. The guy at the shop always comes back from his test drive with a smile on his face and then make a few more tweeks. :ihih: I run 17's all year around. In the Summer I run Dunlop Star Specs 215/45/17 wrapped around a set of Enkei Racing PF01. Love the grip. In the Winter I run Michelin Pilot Sport A/S Plus 2105/45/17 on my beater rims which are MINI R90's. They look good and weigh 26 lbs each. I do not run dedicated snow tires as I don't go out in the snow often but when I do the A/S work great.
This isn't the only factor in how low to run the car, but when the lower control arm goes from flat to angling up at the tire end, the camber gain goes from camber gain to camber loss. The wheel looses camber as the suspension deflects in bump. I don't run any lower than having the lower control arms flat. Flat measured from the center of the ball joint pivot and the center of the inner pivot
I do not run that low and I am sure if I did mess up the ride height my alignment guy, which is a good guy, would have said something along the way of "Dave that may look cool but you are going to destroy your suspension". I also have Helix adjustable camber plates in the front and adjustable control arms in the rear.
In general, I absolutely agree with this. I've relied on the suspension gurus I've found in the MINI community for their suggested drop to get a lower center of gravity, but not increase the roll couple excessively such that the spring rates on a given set of coilvers can't keep up.... or if they can't, they aren't so darn stiff it'd kill me on the street.
Well, I have most everything sorted now, a big part in thanks to this thread and some PMs. It all comes down to the wheel/tire discussion for a car that is driven primarily on weekends on backroads, with a few HPDEs a year (not the the way around u track addicts! ) What would you choose for tire/rim combo that allows the right balance of ground clearance (mind you I will be lowered 1.3in with the suspension), highway RPMs, low tire/rim costs, and GRIP!
The other kicker is gearing. a 205/50 or 225/45 would give great acceleration on a 15in rim, but do you run out of revs down the back straight? Conversely, if u rock OEM sized 205 or 215s on 17in rim, do you not have enough power (basic bolt-ons for an R56 plus tune) to use the gearing down the back straight?
Both Dave and I have modded R53's, I'm at about 250 WHP I think Dave is roundabout that too. The fifteens help with acceleration. I am never in 2nd gear, 3-5 that's it, my car is too squirrelly in 2nd, and I have plenty of torque in 3rd as long as I maintain momentum. You'd have to check the gearing on the R 56 compared to the R 53--I can tell you that acceleration and gearing is better on my car on 15's versus 17's.
Understood on gearing, but if u are "missing" gears because it puts down too much TQ in the lower gears, do you top out on long back straights? Maybe it's wonderful to have power on hand and not have to shift much.
No. But my RPM's are set higher. There are some shorter tracks where I run only 3rd or 4th gear, Blackhawk being one of those, and I'm fairly quick there. It really doesn't matter though--ideally you'd have different gear ratios for each track. There are places on some tracks where it's faster to hug the redline for a split second rather than upshift, only having to immediately downshift. There are other tracks where that never comes close to coming into play. On a long straight, you're more likely going to upshift, I literally can't think of a single long straight anywhere where hugging the redline is an issue--keep in mind you don't want to go to redline in each gear, you want to shift where it makes sense from a torque standpoint. Where it comes into play more is a short straight coming into a turn, and you have to figure out what works best--is it worth the upshift with a quick downshift (usually not), or is it faster to stop accelerating below the redline for a short time before the turn (which is usually faster for me). Now for those who are immortal drivers, it may be different, but for us mere mortals, it's usually smoother and faster not to make the shift.
UKCooper: 20mm spacer seems big to me from what I've read. Have you had any trouble with wheel bearings? Do people fuss over spacers more than they should?
Wheel spacers are not big deal. I run a 12 or 14 mm in the front and a 5 mm in the rear and will not hurt the wheel bearings as long as you buy the longer lug bolts. I get mine from Turner. Wheel Bolt for BMW, MINI - 12x1.50 - Silver - fits most BMWs - Turner Motorsport
Is there a difference between what the 15x8 6ULs can fit vs. the 15 x 7s? I've been reading the 15x8s can fit bigger brakes. (Not sure where the 15x7.5s fit in for me though)
I agree that the fear of spacers is a bit out of proportion, just run them with the right length bolts or convert to longer studs (what I did). The force on the wheel bearings will be ~equivalent to that offset wheel. For my new wheels I specced them to not require a spacer to save on weight but their effective offset will be <5mm difference from the spacer-ed ones so the wheel bearing will be undergoing a similar load. I will say you can feel the difference in the steering weight, scrub radius etc running lower offsets so the difference isn’t negligible but I haven’t had any wheel bearing issues yet. I will your agree to you point about, at least for me that is, my mini is track car first and back up street car second so take that into account. That actually reminds me, when I was daily driving the mini with one set of wheels I ran 16x7 and 205-50-16 on street and track. I bought a bbk that fit under 15’s because I knew when I got a set of track only wheels I would want 15s. It seemed like a decent comprise to me. Lots of my friends run 6ULs so I have test fit the 15x7.5, 15x8, and 15x9 on my car. Due to the backspacing differences you are correct that in some cases you can run a smaller or no spacer on the 8 and might need one on the 7.5. I haven’t tried the 7 but I think that should be easy to figure out with an online offset comparison tool. With oem sized brakes I would GUESS you could run the 7.5 with no spacers. For the gearing question, I wouldn’t get too worried. Ambient temperature has almost as much of an impact in shifting for FI cars in my experience, when I run in the spring/fall I have to use 6th on the 3000ft straight at summit main. But in july I just keep it in 5th. I actually used a session when only 5 cars were out to test leaving the car in gear for a shorter straight versus up and downshift and according to the data it was faster left in gear (for that specific sector) but the next day it dropped almost 20 degrees and shifting up was faster because the car was making more power and running out of gear earlier. On normal tracks I get to ~125 without trouble. Running the oval at MIS I can peg the top speed limiter on the oval before hitting the redline, maybe some folks have removed the limiter but I haven’t messed around with my ecu yet, the R56 might have a higher top speed too, but for the tracks around me I don’t see getting far over 130 which is not a struggle for my gearing with the 225s.
Assuming similar rubber, did the 15 x 7 vs. 15 x 7.5 vs. 15x8s feel any different from each other or am I other thinking it? Thanks for the feedback on gearing, much appreciated!
There is a big difference between 15x7 and 15x8, at least on 225/45's. I have never run 15x 7.5. I currently have 15x9 up front and it's heaven. I was worried about the stagger with 8's in back 9's in front, but that's what Jan was running, a number of people chimed in and felt it was much better, and they were right. Get hub centric/wheel centric spacers from Jan, 18mm up front, and 5mm in the rear and you should clear anything.
Ok, so 225/45/R15s will fit nicely on 15x8s, and I guess 205/50/R15s will stretch a bit (but still be ok?) on 15x8s... http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+Rival&partnum=05WR5GFR&vehicleSearch=false&fromCompare1=yes&tab=Specs
GRM had an article last month about tire/wheel size that lines up with what cct1 said, generalized conclusion was that section (not tread) width approximately equal to wheel width was the fastest. If you want to run a 225 i wouldn't go narrower than 8", if running a 205 then 7 or 7.5 would be fine. I would pick the tire you want to run first then the wheel to best mount that <- advice i got from a much better driver than me I only ran 225s on the 8 so comparison to the 7" wheels where i ran 205 isn't super useful.
Ok, so 205/50 is cheaper, and has a lot more selection and the section with is 8.4", so a 15x8 rim should be ok there and allow me to go to a larger 225/45 tire (8.9" section width) in the future if I ever want to. Thanks for the tip.