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      06-10-2018, 09:53 AM   #111
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Quote:
Originally Posted by SeanWRT View Post
Guys, I'm currently on stock wheel and RE71R. Performance is acceptable. But my issue is, 265 35 19 on rear is a little too tall and 265 on 10j is a little too stretched.

I'm thinking to upgrade rear wheel/tire to 19 10.5j and 295 30 19 to fix the issue.

Will it rub with 20mm lowered MPS and stock camber? The exact tire I'm thinking to do is AD08R on 295 30 19. What else (size/brand) do you recommend? I don't want to go too extreme BTW.

I noticed someone doing fine on 295 30 19 lowered. However OP mentioned TrofeoR rubs but that's really a 315mm tire.

It'd be frustrating me end up buying 10.5j wheel and having to stick to 265 35 19, looking more stretched than it already does.

Thanks!
You can never guarantee these things, but I think you’ll be fine if your 10.5 wheel has a higher offset than stock, like the VMR V710FFs I got with ET45.

I think a 305/30/19 RE-71R would even fit back there on a 10.5 with ET45, but you’d likely need a little more negative camber than stock.

In either scenario, I’d trim the bumper/fender tab to keep from rubbing the tire sidewall.

Take a look at my latest pics to see how the rear looks. I’m about 17mm lower in the rear with 295/30/19 on 10.5s and ET45 with -2.0 camber.
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      06-13-2018, 08:45 AM   #112
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Some pics of my updated setup


Front:

TrofeoR 265/30-19
OEM 10" ET40 REAR wheel plus 25mm spacer
3,1 degree camber


Rear:

TrofeoR 295/30-19
OEM 10” ET40 wheel
2 degrees camber



The car is just very sligthly lowered to Öhlins Road & Track default setup

The 265 in the front sits much better on the 10" wheel. I felt a sharper steering response, although it might be placebo

I also felt a very small increase in tramlining, still on a very nice low level in general. This increase is maybe more due to the wider track (more scrub) with the ET/width change rather than the wider wheel stretching the tire a bitmore. Maybe. I think a 20mm spacer rather than the 25mm I had in hand would be more optimal. But this seems to work. I'll keep an eye on rubbing issues on track.
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      06-13-2018, 10:56 AM   #113
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How close are you to the strut? Do you think you could go all the way down to a 15mm spacer, so the ET is closer to stock?

My 265/30 fit on a 9.5 ET33 with no spacer, so I think you would still have clearance with just a 12-15mm spacer.
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      06-13-2018, 01:38 PM   #114
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Quote:
Originally Posted by ZM2 View Post
How close are you to the strut? Do you think you could go all the way down to a 15mm spacer, so the ET is closer to stock?

My 265/30 fit on a 9.5 ET33 with no spacer, so I think you would still have clearance with just a 12-15mm spacer.
I haven't measured, only have a lousy photo that you can see below.


Stuff that I've tested with the Öhlins R&T on the car:


9" ET19 (ET29 and 10mm spacer) TrofeoR 265/30-19 = OKAY

9" ET24 (ET29 and 5mm spacer) TrofeoR 265/30-19 = OKAY but wouldn't track it...

9" ET23 (ET33 and 10mm spacer) Nankang AR-1 265/35-18 = OKAY (but never checked the clearance)

9" ET29, TrofeoR 265/30-19 = FAIL, made a 1-2mm deep scratch in the tire

and

10" ET15 (ET40 and 25mm spacer) TrofeoR 265/30-19 = OKAY with room to spare to the strut. Could be tight to the fender on ride height compression. Will see...



The thing is that it's the Öhlins height adjustment that is tightest to the rubber and that's high up on the tire wall, about 1-1,5 cm down from the shoulder. This means that the tire width plays a larger role than wheel width (touch point being far away from the wheel rim but close to the contact patch part of the tire) but the width of the wheel will affect how close you can go too. Sorry for a strange explanation, english is not my strongest point.

This shows a bit what I mean:
https://www.willtheyfit.com/index.ph...=10&offset2=15
EDIT: added pic from willtheyfit
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Last edited by MagnusT; 06-13-2018 at 01:59 PM..
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      06-13-2018, 01:57 PM   #115
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Makes sense. Guess you’ll have to find some buddies with spacers that fit to try some other sizes.
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      06-14-2018, 01:45 PM   #116
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Quote:
Originally Posted by ZM2 View Post
I’ll try lower again, but anything under 35 and the car was extremely loose. A buddy of mine does a lot of race coaching and he said his customers’ Lambo’s grip best with their Trofeo Rs around 40psi. I thought that was high, so asked another racer/car setup engineer and he also said the Trofeo’s like high pressures.

Ambient was 50-70F when I ran and had rained the night before. I was able to pull 1.1g with them consistently, tho, and wear looked good.
Ran higher pressures on sunday's trackday. 2,6 bar worked very well. So I agree that they seem to like higher pressures!
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      06-17-2018, 06:18 AM   #117
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Since it's a bit hard to measure the distance between the strut and tire without having the car on a proper lift I used some material that behaved like play-doh and squeezed it between the strut and wheel.

What I noticed was:

- the available space with the Öhlins on the car is VERY sensitive to chosen ride height. The Öhlin's height adjustment nut and the bottom of the spring is on my car touching the tire high up on the tirewall / on the shoulder. See pic below. Raising the car 5mm would give a lot more horizontal clearance. And vice versa.

- measuring the play-doh's horizontal clearance at the worst point gave me aprox. 8-9mm. So to go from a 25mm to a 20mm spacer should be ok. But I really don't know what the absolute minimum clearance should be, measured when the car is standing still.
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      06-18-2018, 10:25 PM   #118
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I am switching to a square set up for use on my car which is now becoming a daily driver and 3 track days per year car...the car is set up with Ohlins R&T

I am considering running a square set 18x9.5" ET35 - Do you know whether or not 265/35-18 and/or 255/40-18 tires will fit without camber plates?

Thanks for any advice or experience you can share.
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      06-18-2018, 11:09 PM   #119
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One of our local M2 jockeys runs square 265/35-18s on 9.5x18 et35s. I’m running the same tires on 9x18f/10x18r with stock offsets. Both on stock suspensions.
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      06-19-2018, 10:23 AM   #120
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Quote:
Originally Posted by MagnusT View Post

- measuring the play-doh's horizontal clearance at the worst point gave me aprox. 8-9mm. So to go from a 25mm to a 20mm spacer should be ok. But I really don't know what the absolute minimum clearance should be, measured when the car is standing still.
I run with about ~3mm inboard clearance without issues; autocrossing, tracking, no problems.
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      06-19-2018, 12:56 PM   #121
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Quote:
Originally Posted by rwalker View Post
I run with about ~3mm inboard clearance without issues; autocrossing, tracking, no problems.
Picked up the 20mm spacers today, will try to get the car on a lift and measure when I put them on. Thx for the feedback!
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      06-20-2018, 07:14 AM   #122
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Quote:
Originally Posted by Old Geezer View Post
One of our local M2 jockeys runs square 265/35-18s on 9.5x18 et35s. I’m running the same tires on 9x18f/10x18r with stock offsets. Both on stock suspensions.
What tires are you running?
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      06-20-2018, 07:38 AM   #123
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Quote:
Originally Posted by chief1richard View Post
What tires are you running?
Bridgestone RE-71R
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      06-20-2018, 07:54 AM   #124
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Quote:
Originally Posted by Old Geezer View Post
Bridgestone RE-71R
That's the set-up I've been trying to find out if it will fit. 265/35 35 offset 18 square with RE-71's. No rubbing or clearance problems with stock suspension? Thanks. I want to keep my suspension stock, but want max rubber for track.
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      06-20-2018, 08:03 AM   #125
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Quote:
Originally Posted by chief1richard View Post
That's the set-up I've been trying to find out if it will fit. 265/35 35 offset 18 square with RE-71's. No rubbing or clearance problems with stock suspension? Thanks. I want to keep my suspension stock, but want max rubber for track.
That should work with no issues. I’m not a track guy, but for autocross I’ve found 265 to be plenty of tire.
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      06-26-2018, 04:18 PM   #126
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So I got the 20mm spacers, replacing the a bit to wide 25mm ones. Moving the front wheels 5mm inwards on each side. No other changes done.

Very little tramlining left now. Impressingly little for 265 tires and 3.1 degrees camber IMHO.

This setup works but free space between rubber and the Öhlins is minimal. I think rotating the springs slightly can give some optimization but the height adjustment nut is where it is...



So:

Front:

TrofeoR 265/30-19
OEM 10" ET40 REAR wheel plus 20mm spacer
3,1 degree camber


Rear:

TrofeoR 295/30-19
OEM 10” ET40 wheel
2 degrees camber



The car is just very sligthly lowered to Öhlins Road & Track default setup
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      07-01-2018, 09:26 PM   #127
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I test fitted the rear wheels with stock Michelin Pilot Super Sport (265/35/19) on the front of my stock M2. The tire touches the shock on the inside and the outside is almost flush with the fender.

I was thinking a 5mm spacer would be sufficient to get shock clearance. Then maybe -1.8° to -2° front camber with zero toe may work for outside clearance on a street car.

MagnusT - Thanks for sharing your setup. Looking at the picture of your wheel well, I am thinking you can go thinner than 20mm, but could be wrong.



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      07-01-2018, 11:34 PM   #128
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It's actually very very tight with 20mm spacer with 10" rear wheel and TrofeoR 265. Under 5mm clearance to the bottom bit of the spring and height adjustment nut on the Öhlins. Semislicks/R-tires are usually quite a bit wider than normal tires with the same width rating.

This is with 25mm spacer. I could gain a few mm clearance by turning the whole spring so the first bottom turn is further anticlock wise.
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Last edited by MagnusT; 07-01-2018 at 11:41 PM..
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      07-22-2018, 04:14 PM   #129
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I did the play-doh test at the front again but with the 20mm spacers (and OEM 10" rear wheels). I'd say I have somewhere around 3mm clearance to the Öhlin's height adjustment nut and spring. But no rubbing at all even on track and autox with the TrofeoR 265s
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      07-24-2018, 07:05 AM   #130
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So...I get my alignment checked each time before I go to the track, but I must have hit a pothole bc it was off when we put it on the rack this time.

This may be the source of my tramlining complaints last time out, and not the Trofeo’s. Will find out at the track this weekend.
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      08-02-2018, 05:52 PM   #131
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Quote:
Originally Posted by ZM2 View Post
So...I get my alignment checked each time before I go to the track, but I must have hit a pothole bc it was off when we put it on the rack this time.

This may be the source of my tramlining complaints last time out, and not the Trofeo’s. Will find out at the track this weekend.
No tramlining. Must have been bc the alignment was knocked out of whack.

Overall, the Trofeo R’s are the best streetable track tire I’ve used. Relatively quiet on the road, doesn’t overheat, great grip, and very controllable at the limit. They lasted about 10 track hours before heat cycling out. Tread was close to gone too.

They are pretty expensive, so I’ll try another set of 71Rs to see if I can live with those since they’re a lot cheaper.
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      08-15-2018, 08:07 AM   #132
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Quick update:

I ran 265/35 & 295/30 Hoosier R7s on the car at an open track day last week. I believe this is the Max Rubber you can get on a track prepped M2 with camber, lowered suspension, and the correct wheel specs.

I originally tried 295/35 R7s in the rear, but they were too tall and had to go 295/30s. They don't make 265/30 R7s, but the balance was still good front to rear and there was tons of grip and it was a blast!

For cheaper tires, I think I can fit a 305/30 RE-71R in the back, but I probably won't try that until next year.

Again, this is with 19x9.5 ET33 fronts and 19x10.5 ET45 rears. I did need a 3mm spacer for the R7s to clear the front suspension, no spacer needed for the Trofeo’s.

Last edited by ZM2; 08-15-2018 at 10:34 PM..
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