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Discussion Starter #61 (Edited)
I never had any issues running this set-up. I have since retired the M6 from track duty and returned it to street driving only. Only tip i can give is rotate the tires at least after every 4 sessions. The front outside edges wear very quickly, so rotating often will help tire life, especially if you have factory spec camber. PM Sidney Page....his username is spiceman....he posted up above in post 54 of this thread. He is a good friend of mine and he tracks his M6 here locally with me. He followed my footsteps with the same size Apex wheels and Nt01 tires, but has taken it a step further with coilovers, camber plates, and larger sway bars. I believe he is getting much longer tire life with this set up than i ever did with just lowering springs and factory spec camber.
 

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Through my personal experience and guidance from Keith the performance is amazing compared to a stock setup. With your experience you will feel a big difference that will be well worth the cost of the wheels and tires. I’m also thinking that you may actually save money in the long run by not eating up your street tires. Look into the cost. It is not as much as you actually think. As Keith said being able to rotate tires from left to right and front to back will extend the life and endurance of your tires. As previously stated in this thread the tire choice is strictly a preference.

I also highly recommend the front & back sway bars. That was a huge difference in apexing through the corners and not a big expense. If you look into coilovers please PM me or someone who has gone down this road. There were some challenges to make the whole setup work with the Apex wheels and offsets.
 

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Thanks -- I have significant experience (BMW 2-day M School, Advanced M School, 2 days at Circuit of the Americas, completed the level 1, 2, 3 and advanced road racing classes at my local track and more than 20 HPE events). Really, I am at the limit of what my street tires on stock wheels can offer (I have springs and RD sway bars). Was interested in the feedback from those running this set up and whether the performance gains/increase in fun, will offset the cost. Obviously, there's no good way to lose 1,000 lbs of weight, but would like to improve the performance somewhat. Have heard that on the slicks the breakaway can be uneven. Thoughts on this set up/worthwhile?

Thanks.
RDSport sway bars will go a long way in saving your front tires from understeer.

I swapped out from Dinan's FRC and RSB and the difference was immediate.

Another great upgrade to improve steering, consider Dinan's monoballs. I was blowing through LCAs -- not any more!

In retrospect, I don't know why I waited a couple years before swapped for the RD sways and monoballs. Well, the reality is, I wanted to feel the limits of the car stock, then add one mod at a time, to isolate the effect of each mod.

I have yet to go to the 18" APEX wheels or R-compounds with this car -- I ended up with some LTW Dinan 19"s that are 19#s-ish. Combined with my BBK, I shaved at least 15# per corner.
 

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Thanks guys, really appreciate the feedback. I pulled the trigger and went with the Apex EC-7s in the 18x9.5 square set up. I chose the EC-7s because they have more break caliper clearance than the ARC-8s -- not an issue with the stock calipers, but it would be an issue if I went with a 380mm BBK. I chose Toyo Proxes RA1s from tirerack with their heat cycling service, for a less aggressive, first time on R-compound tire. Also, some of the reviews suggest that they may hold up a little better, though with a bit of performance sacrifice as compared to some of the newer/more aggressive tires. The compound has a 100 wear rating vs. 40 for some of the others, but less than the 400 or so on the tires I am running now. I appreciate the tip about rotation, with the square set up this should make it easy. The driver-side front tire tends to take the brunt of the cornering force and shows wear the quickest. My rears generally show little wear as compared to the front. I was worried about running R compounds on such a heavy car, but I figured it was worth giving it a shot. I'm not looking to win any podiums, but am interested in hanging a little closer to some of the lighter, but less powerful cars through the turns.

I have H&R springs and RD Sway bars -- both of which made a huge difference. I am running about -1.25 degree of negative camber in the front, which is at the limit of the stock set up. I will consider adding camber plates in the future, depending on how hard the wear on the tires is. At the same time, this is my daily driver, and I haul the wife and the baby, so I can't totally sacrifice the ride. This is one of the reasons I haven't really considered going to a full coil-over set-up.

Did you feel the Dinan monoballs and/or camber plates were a worth-while addition? What was the impact on driveability?

Thanks again!
 

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Edit: Double post deleted
 

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Discussion Starter #68 (Edited)
Awesome! Nice choices! I know everyone has their own opinion on tire rotation.....but I found what worked best for me was moving the rears straight forward, and crossing the fronts to the rear. I did this same sequence every 3-4 sessions and got about 20-30, thirty minute sessions out of a set of NT01's with -1.7 degrees camber on the front. Also, make sure you play with the air pressure. You want them around 34-35 psi hot.....which for me equaled 24-25 cold. R comps seem to be very happy with those hot pressures.
 

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Tire wear depends a lot on (1) the track and (2) driving style. For example, my left front gets the most wear at VIR (makes sense given the track configuration), but the rears get considerably more wear at Mid-Ohio. If you are using DSC, your rear tire wear will be less. Best to monitor the wear and rotate as you see fit. I normally will put the best tire on the position that takes the biggest beating.

How long your tires will last depends mostly on how much degradation in performance you are willing to tolerate. The more aggressive the compound, the less durability. For example, I use Hoosier R6s on my e36 M3 race car. There is a noticeable fall off after three or four heat cycles, and they are not very competitive after seven or eight heat cycles. A proper scrub-in can extend the life by a couple of heat cycles, but most racers buy a new set of tires for each race weekend due to the degradation. If you are not racing, and using less aggressive rubber than Hoosiers or BFG R1s, it is reasonable to expect many more heat cycles than that.
 

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All -

To close loop on this, I went with the Apex EC-7s with Toyo Proxes RA1's in 275x35x18 on all four corners. My car has H&R springs, RDSport Sway bars and about -1.5 camber in the front. I also have stainless break lines, and installed new cool carbon pads on all four corners, new front rotors with re-surfaced rears and race-spec break fluid (all of which you should do before any high performance driving event).

This weekend was the BMW CCA event at the Circuit of the Americas (F1 Track) in Austin, Texas. The tires held up great over 3 days, 3 sessions per day, for a total of 9 30 minute sessions. In between track sessions, and overnight, I would drive the car back and forth to my house on the public roads. I also drove the dog and the baby to grandma's house one morning (probably the only one who can say that of their track set up). All-in-all between track time and miles back and forth to my house/grandmas I put almost 800 miles on the tires this weekend.

I have to say that the tire and wheel upgrade had a noticeable impact in handling performance both on the street and very much on the track. While I plan to remount my stock wheels and tires soon (for wear and rain issues), the EC-7s with the RA1's was the best compromise between price, longevity, increased performance and liveability during a track weekend. I didn't have to change back to street tires or trailer my car, as many others at the event did. Just roll off the track, do a bit of a cool down, and head straight home or to lunch or wherever. No muss, no fuss.

By the last run on the last day the fronts were starting to show some noticeable wear and a decrease in grip. The rears still look great. I'd estimate that rotating front to rear will get me another 2-3 track days on these tires with 3 or so sessions each day. I did not rotate over the course of the weekend, as I decided not to take the time or invest the effort to do it. Had I done so, I may have squeezed a little more performance, but it wasn't worth the effort. I ran at 32psi cold, and the tires would heat up to around 40psi by the end of a session.

In terms of performance, I was running with two of my friends, both of whom have Porsches. One is a 2010 Cayman R on full A6 Hoosiers, with a few other performance mods (trailered to and from the event). The other is one is new stock 991 Carerra S on street tires, with some negative camber dialed in. My best time on the circuit was a 2:47 -- though I think there is a 2:45 in this set up (pending driver improvement and a little less traffic). The Carerra S's best time was a 2:41. The Cayman R's best time was a 2:38, though when he was running Toyo R888s his times were in the lower 2:40s. So, all-in-all, having a 4,000lb, 4 door sedan running respectable times in a streetable condition vs a gaggle of Porsches is pretty good. As a further FYI, the BMW Club racers in street illegal cars were running between 2:19 up to the 2:50s (see results from last year here: http://www.bmwccaclubracing.com/_Uploads/RaceResults/COTAJun2013resultsrevised.pdf).

I'd highly recommend upgrading the wheels and tires to anyone who is on the fence. I would not have had anywhere near as enjoyable of an experience without them.
 

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Discussion Starter #71 (Edited)
Sweet.....any pics with the set-up? A 275/45/18 puts the rolling diameter larger than the stock front 255/40/19's, I believe.
I've thought about running my 18's on the street, but cant decide what tire sizes to go with.
Yeah, you would def extend the tire life by rotating. I rotate mine on my z06 at the end of each track day which equates to rotating after four, 30 minute sessions. My z06 is corner balanced with -3 degrees of camber, so the tires do wear evenly, but I do still rotate
 

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Here's two pictures, not the best quality/angle to show the wheels/tires, but its the best I have. I think camber plates and an earlier rotation will be in store prior to the next track day. There was a Z06 in our group, and he cooked his brakes -- smoking and boiling fluid.

Note: I ran 12.5mm spacers in front, no spacers in the rear. Interestingly, the rears, with 12.5mm spacers rubbed a little, so I removed them. No rubbing with the spacers in the front and no spacers in the rear. As to rolling diameters, I noticed that my speedometer was reading a bit higher than I was actually travelling -- assume this is because the rear wheels are rotating more in the 18inch diameter -- but not totally sure.
 

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Discussion Starter #73
You sure those are 275/45/18's? According to the tire calculator that size is larger in diameter than the stock 285/35/19 and 255/40/19...if that's the case your speedo should be reading slower. In any case your car looks great with the EC-7's!
Yeah, the stock Z06 brakes suck big time.....I burned through several sets of stock rotors and pads before I finally swapped over to a 355mm Stoptech BBK with Cobalt pads. Much much better....I had already swapped over to Motul 660 brake fluid...so boiling has never been an issue. I did the same thing in the M6 as well when I tracked it.
 

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You are right -- they are 275/35/18 -- not 275/45/18. Updated/corrected in my earlier post.

Surprisingly, and so far, the stock M5 brakes/rotors with stock pads and with cool carbon pads have held up well. Though I've always run the Motul brake fluid and stainless lines. No overheating issues, no noticeable fade, and COTA is hard track on brakes (slowing from ~115mph to ~35mph while entering the back straight followed by ~145mph to ~35mph at the end of the back straight). There's also a hard braking zone at the top of turn 1 (~115mph to ~35mph), which was where the Z06 finally lost his brakes -- though I saw and smelled them smoking a few turns earlier in the session.

Now, I just need to figure out how to get the M5 to lose 1,000 lbs, and it'll be a real track car!
 

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Discussion Starter #75
Ok, yeah, that makes more sense..lol. 275/35 is what I was running on the M6.
My wife ran COTA back in Feb with MVP in the Z. She had a blast
 

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You are right -- they are 275/35/18 -- not 275/45/18. Updated/corrected in my earlier post.

Surprisingly, and so far, the stock M5 brakes/rotors with stock pads and with cool carbon pads have held up well. Though I've always run the Motul brake fluid and stainless lines. No overheating issues, no noticeable fade, and COTA is hard track on brakes (slowing from ~115mph to ~35mph while entering the back straight followed by ~145mph to ~35mph at the end of the back straight). There's also a hard braking zone at the top of turn 1 (~115mph to ~35mph), which was where the Z06 finally lost his brakes -- though I saw and smelled them smoking a few turns earlier in the session.

Now, I just need to figure out how to get the M5 to lose 1,000 lbs, and it'll be a real track car!
You could do a factory door and cylinder delete...oh wait...then you'd have an e92 and s65. :tonquesmilie:
 

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Woody -- I see you are running the CKS coils w/swift springs. I'm considering this, and I know you said to touch base with you regarding the coilovers. What are your thoughts? Any issues I need to be aware of? How's day-to-day driveability?

And yes, COTA is an awesome track, well suited for our big and heavy cars, as it is a bit less technical and tight than many others.
 

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Woody -- I see you are running the CKS coils w/swift springs. I'm considering this, and I know you said to touch base with you regarding the coilovers. What are your thoughts? Any issues I need to be aware of? How's day-to-day driveability?

And yes, COTA is an awesome track, well suited for our big and heavy cars, as it is a bit less technical and tight than many others.
Yes, I'm running CKS w/swift springs that I had installed about 22,000 miles ago. I'm coming from my e28 m5 and e39 m5 that are also on coils. My e28 is scalpel on a fully adjustable Ground Control system: camber plates, powerflex bushings, thicker f/r sways and stress bars, control arms, etc... My e39 is not as aggressive, no camber plates and bushings, but set up similarly.

When it came time for the e60, I went from a Dinan Stage II to RDSport lowering springs to CKS w/swift springs and RDSport F/R sways. I know Ground Control will build something for the e60 m5, which I was going to do because of my e28. GC never got back to my shop's inquiries, so I passed.

Many e60 guys will run KW v3, which I was about to do, but I decided to try something new with the CKS set up. The only thing I will point out, CKS only has a limited warranty (one year I think) that board member (and friend) Hasan Shaikh clarified for me. So far, no drama...at the track or freeway for the last 22,000 miles. No squeaks, no nothing. I'm considering adding some GC camber plates for more negative camber for track days, but that's about it.

This is how she sits:

http://www.m5board.com/vbulletin/e60-m5-e61-m5-touring-discussion/295593-just-few-pics-other-day-nothing-professional.html

And this is how she corners with no understeer:
 

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Looks great -- I'm really considering the coils + camber plates for the next step. You are happy with the coils in day-to-day driving situations? You notice an improvement in performance vs. the RD lowering springs you had previously? I'm currently on the RD sways with H&R springs, trying to gauge if the performance jump to the coilovers is worth the extra $$.

P.S. your car looks great!!
 

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Looks great -- I'm really considering the coils + camber plates for the next step. You are happy with the coils in day-to-day driving situations? You notice an improvement in performance vs. the RD lowering springs you had previously? I'm currently on the RD sways with H&R springs, trying to gauge if the performance jump to the coilovers is worth the extra $$.

P.S. your car looks great!!
Thanks for the kind words...Yes...HUGE IMPROVEMENT...worth the performance jump if you spend any time at the track.

The day to day is fine, and you can always dial up/down the rebound at the shock, without crawling underneath the car. There is no EDC for any of the coil systems for the e60, but you still have the adjustability. Now, when I drive a "softer" car, things feel strange.

The reason I went to springs first -- I wanted to keep the EDC functional. I also didn't think I would ever track my e60 -- well that didn't last too long. Is there really anything funner than running down coupes on the track, with a 4 door grocery getter? I will probably retire my e60 from track days when I get my e28 back from her restoration/build, but I'm just having too much fun tossing around the grocery getter.

In retrospect, I should have (and saved some money ouich) just gone with the coils and skipped the springs. The springs are fine, but you get so much more flexibility with the coils -- the rebound adjustment for smooth or bumpy tracks/infields and the height adjustment for different width/size wheels and tires. I had to raise my rears by 5mm when I went from 295 to 305...

Again, I would have been all over the APEX wheels, had I not found my Dinan wheels. When I met their rep at Bimmerfest last year, he was showing us how their wheels 18" would clear my Stoptech BBK -- which is huge (no pun intended :tonquesmilie:).

I hope that helps!

:cheers:
 
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