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      11-12-2019, 05:41 PM   #45
jprice130
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Originally Posted by SafariEdition View Post
Haha well thank you! I know of some people who have done similar set ups on some other M cars (a semi-local driver had 275 RE71r up front and 295 yokos on the rear) and seemed to like it. My thoughts are that this is going to cause understeer, which from my understanding, with a front bar they are already struggling with that. I highly doubt you'll be struggling with power down, especially with the yoko's on the back...the diff is REALLY good.. so I think a 265 all around would benefit you better...though you do lose out on the flipping portion. The other thing to note, the tire sizing you're looking at is going to lift the rear up pretty high...I'm not sure how sensitive the M2 is to rake, but I know when I made those kids of changes on the C5 Z06 I ran last year, it made some really drastic changes to how it handled. Ultimately, I think the best options are either 265 squared yokos, 285 squared RE71r, or if theres a way to stuff 295's, MAYBE the 295 yokohamas all around.

For these cars, the RE71r's might be the best option because I dont think the yokohamas have as much of an advantage over the stones with the lack of camber the M2 can get,and the way we're likely to beat up on the fronts, the yoko's are probably going to be a much more expensive way to go....

With that being said, one of my good friends won FS at Nats on 265 squared Yokos on an E92 M3 that gets less camber than our cars...so YMMV
Thanks for the extra feedback! Definitely a lot to think about. Thankfully my season is over, so there's no rush to make a decision. Will keep you posted...
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      11-12-2019, 05:50 PM   #46
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I'll also be testing things, and seeing what may or may not fit and what spacers may be necessary.... When the A052's first came out I did a ton of testing on them and on sizing for AS cars, I'll be happy to do the same share all the info I find with the M2 on here too =)
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      11-13-2019, 02:37 AM   #47
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Interesting idea of the RE71r in front and A052 in rear. As Devin said, the rear diff works very well, and putting power down is not such an issue to me. Fitting tires and getting the front end to turn is totally the goal. In BS, you are limited to 9" wide wheels in front and 10" wide in back. Depending on how you feel about squeezing wide tires on narrow rims, maybe it can work. For me, it seems unlikely I would go wider than my current 275/35-18 on the fronts. A 285mm or 295mm front tire would be interesting to see. Just keep in mind the front tire clearance issues are the tire rubbing on the strut housing, and tire rub on the fender opening (as when tires turned, compressed). This is where a lower overall height tire in front is good. A taller tire may contact the fender on compression. I changed my rear tire sizes more for gearing than grip, but as always its a balancing act. Would love to hear more of others combo of tire/wheel sizes and impressions.
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      11-13-2019, 08:18 AM   #48
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Originally Posted by toy4speed View Post
Interesting idea of the RE71r in front and A052 in rear. As Devin said, the rear diff works very well, and putting power down is not such an issue to me. Fitting tires and getting the front end to turn is totally the goal. In BS, you are limited to 9" wide wheels in front and 10" wide in back. Depending on how you feel about squeezing wide tires on narrow rims, maybe it can work. For me, it seems unlikely I would go wider than my current 275/35-18 on the fronts. A 285mm or 295mm front tire would be interesting to see. Just keep in mind the front tire clearance issues are the tire rubbing on the strut housing, and tire rub on the fender opening (as when tires turned, compressed). This is where a lower overall height tire in front is good. A taller tire may contact the fender on compression. I changed my rear tire sizes more for gearing than grip, but as always its a balancing act. Would love to hear more of others combo of tire/wheel sizes and impressions.
Agreed, which is why the 295 Yokohamas are interesting to me... they are about half an inch shorter than a 275/35R18 RE71R in overall diameter... I'm thinking with the right spacer size they MIGHT work. Unfortunately, Thats something that will have to wait til spring for me to be able to bring everything in to have it measured at work and see if it will clear on both sides or not...and then theres no telling if it will actually drive/feel very good...but I have a hunch that it will, with that particular tire.
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      11-15-2019, 01:03 PM   #49
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Would love to hear feedback on a 295/30-18 tire on the front 18x9 wheels. I'm pretty sure with proper offsets/spacers the lower OA diameter of the 295 should clear suspension components and fenders, but still uncertain of the 295mm on a 9" wheel. However, you would be able to evaluate better than most! Thank you for your efforts!
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      12-04-2019, 04:00 PM   #50
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Regarding the mixed set (RE71R/Yoko), I ran the 285/30-18 Stones front with 295/30-18 Yoko rears at Nat's in my M3. It was magic, my driving less so. Ido W. (owner of the winning car) took it for a run on the practice course and was grinning ear to ear. They immediately changed plans and ran the Yoks. At least one top tier BS competitor who can identify himself here also tested this setup for his M2, and agree this was the setup. Foley and Emmert mounted 295F/315R Yoks on their 1M wheels which seems crazy. I suppose if you can get the 295's on front, I'd go that square.

I ran the mixed set because I previously ran at the Peru tour the 265/295 Yoks and hated how bad the front of the car was but loved the grip in the rear. Car would just not take a set. On the practice course, a spent set of 275 Stones paired with the 295 Yok's was .3 faster on a 32 second course...first run. Drove back from Peru, thought about what would work with the 295 rear Yoks and settled on the 285/30 Stones. For anyone so inclined, mounting the 285 Stones on a 9" wheel can be a total PITA.
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      12-07-2019, 11:10 PM   #51
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My preference would be to run a square tire setup if I could fit a good size tire, but not sure there is one that fits well. The 285 stones/295 yoko combo does make some sense. Yes, I bet mounting those fronts are a challenge, but I'm thinking a lot of the improvement in handling might be from the significantly lower ride height. That 285 front is about 1" shorter tire than stock, and the 295 rear is pretty close to 1" shorter too. Downside is lower top speed in gears if top of 2nd gear is a big deal, otherwise top of 2nd is decreased to about 63-64 mph? Probably good on smaller tight courses, no shift to 3rd anyway. I'm curious to see if there will still be good interest in the M2 as a B-Street contender next year. Not sure at the moment if I'll stay with the BS setup, or go camber plates and wider front wheels and just play for fun.
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      12-10-2019, 09:17 AM   #52
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Quote:
Originally Posted by z3papa View Post
Regarding the mixed set (RE71R/Yoko), I ran the 285/30-18 Stones front with 295/30-18 Yoko rears at Nat's in my M3. It was magic, my driving less so. Ido W. (owner of the winning car) took it for a run on the practice course and was grinning ear to ear. They immediately changed plans and ran the Yoks. At least one top tier BS competitor who can identify himself here also tested this setup for his M2, and agree this was the setup. Foley and Emmert mounted 295F/315R Yoks on their 1M wheels which seems crazy. I suppose if you can get the 295's on front, I'd go that square.
I'm going to start running my '11 E92 ZCP in F-street next year and thinking about running the 285/30 'stones, and 295/30 Yoko's in the rear, and was wondering which sway bar did you use for this setup? Some have suggested running the Dinan E90/92 non-M front sway bar.
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      12-10-2019, 05:41 PM   #53
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I'm going to start running my '11 E92 ZCP in F-street next year and thinking about running the 285/30 'stones, and 295/30 Yoko's in the rear, and was wondering which sway bar did you use for this setup? Some have suggested running the Dinan E90/92 non-M front sway bar.
I had the E92 M3 Dinan sway bar which I ran in the mid setting. Cashmore ran it full stiff and Tony's car owner ran in soft until Peru and ran it mid setting at Nat's.
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      12-30-2019, 11:42 AM   #54
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Quote:
Originally Posted by z3papa View Post
Regarding the mixed set (RE71R/Yoko), I ran the 285/30-18 Stones front with 295/30-18 Yoko rears at Nat's in my M3. It was magic, my driving less so. Ido W. (owner of the winning car) took it for a run on the practice course and was grinning ear to ear.
Yeah, Ido is a pretty good friend of mine and he told me about his drive in your car and how much he liked it. Thats most likely what I'll end up doing if I cant get the 295's to fit up front. I'm not so worried about the 295's on a 9" wheel...I ran them on a 9.5 in AS and REALLY liked it. the extra half inch may be what makes/breaks it, but wont know til I try.

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Originally Posted by toy4speed View Post
... but I'm thinking a lot of the improvement in handling might be from the significantly lower ride height. That 285 front is about 1" shorter tire than stock, and the 295 rear is pretty close to 1" shorter too. Downside is lower top speed in gears if top of 2nd gear is a big deal, otherwise top of 2nd is decreased to about 63-64 mph?
Another friend of mine did the math on the 295 for the rears. You may lose some gearing top speed for 2nd, but you make up a lot of torque to the ground. It puts the torque closer to what the M2C has, which should help even the playing field between them. Again, not sure if the benefit will outweigh the loss in top speed, but we'll have to see.
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      02-09-2020, 11:59 PM   #55
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End of last season, at an autox at Crows Landing, a very large concrete site with courses often 70 secs+, my '18 M2 kept getting a TPMS warning. We were running the RE71 tires at 29-30 psi, and I believe the TPMS sensors read about 2 psi low. Anyway, each lap, about 3/4 of the way, the TPMS warning would come, car would go into comfort mode. This was after starting the tire pressure reset prior to each lap. Normally run in DSC (TC) fully off. Made the last 2 slaloms and 180 turn fairly sluggish.

So, today I removed the TPMS sensors from my autox wheels. Excited to see how the car responds at an autox. Hard to get on the car enough around the neighborhood to feel if DSC (TC) fully off stays off through all the modes (comfort, sport, sport+). I definitely have comfort, sport, and sport+ functioning as normally would with sensors. MDM also working as usual. Turning DSC fully off also as usual.

What I am not sure yet about is if I turn off the DSC fully, then change mode to sport+, if the car will have the throttle/steering settings of sport+, and still allow the DSC to remain fully off. It "feels" like it might, which would be a nice combo to have. In stock form, with TPMS sensors, turning DSC full off, then changing mode to sport+, will also change the DSC to MDM setting, and the DSC full off is no longer available.

Lots of varying info online, and perhaps M.Y. '16 and '17 is different, but I hope to clarify this for the '18 LCI models. There is also some opinion that the M2C may have different modes available when running without TPMS sensors.
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      02-10-2020, 07:36 AM   #56
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My experience with the M2C is that it will allow DSC fully off while it's doing a TPMS reset, and it won't complete the reset until a certain speed is reached for a long enough time. I was concerned about the issue at my first event with the car, so I reset it before each run. The M2C displays a percentage count up to being fully reset, and on any given run it would only get to 30-40% complete range; however, it allowed DSC fully off and Sport+ without issue.
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      02-11-2020, 08:29 PM   #57
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My experience with the M2C is that it will allow DSC fully off while it's doing a TPMS reset, and it won't complete the reset until a certain speed is reached for a long enough time. I was concerned about the issue at my first event with the car, so I reset it before each run. The M2C displays a percentage count up to being fully reset, and on any given run it would only get to 30-40% complete range; however, it allowed DSC fully off and Sport+ without issue.
Most of my events last year I was able to start a TPMS reset just prior to each lap, and the reset never completed prior to the finish of the lap. Then we went to a bit larger site, runs normally 70 secs to often 80secs+. At this location the TPMS resets were able to reach completion, then kicked us into comfort mode. We were running fairly low tire pressures by then, around 29-30 psi.

Very possible the M2C has different parameters, if so I am envious!
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      02-12-2020, 06:22 AM   #58
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Quote:
Originally Posted by toy4speed View Post
Most of my events last year I was able to start a TPMS reset just prior to each lap, and the reset never completed prior to the finish of the lap. Then we went to a bit larger site, runs normally 70 secs to often 80secs+. At this location the TPMS resets were able to reach completion, then kicked us into comfort mode. We were running fairly low tire pressures by then, around 29-30 psi.

Very possible the M2C has different parameters, if so I am envious!
I think it must have a different setup. At the CCA O'fest my run group was about 15 cars, and after each run we returned off the course, drove a long way down a grid road, made a u-turn and then got back in line. I think I went four runs like that without shutting off the car. It would show 99% on the reset scale, but it never completed. I think it wanted to exceed some level of speed for a given amount of time, and that wasn't completed. The course was long and very fast in spots too (at the Michelin Proving Grounds, aka Black Lake).

Just recently when running at a CCA event at the PerfCenter, I let out a ton of air in the fronts to keep them at 34psi over the space of many runs. The course is very long (85 seconds) and very fast on their track, so the brakes get super hot as one would expect. Anyway, after a long cool down for lunch, the tires were around 28psi. I should have taken a picture of the display since it didn't say immediately inflate and throw a warning, but it did state something about checking the owner's manual and the tire pressures -- some sort of intermediate warning I guess when it sees all four tires near same level but not too crazy low? After a few runs (we all had many runs) and up to temp and pressure, that message just stayed on the screen. It didn't interfere with DSC off at all fortunately.
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