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[loklok1]

Hi I'm looking to get the BBS CH-R 20' with the following tire size. I'm wondering if anyone knows if this configuration would rub on stock suspension setup? Any comments would be much appreciated thanks.

F 20x9 - ET +24
265/30/20

R 20x10.5 - ET +24
295/25/20
or
295/30/20

[LarThaL]

Originally Posted by loklok1

Hi I'm looking to get the BBS CH-R 20' with the following tire size. I'm wondering if anyone knows if this configuration would rub on stock suspension setup? Any comments would be much appreciated thanks.

F 20x9 - ET +24
265/30/20

R 20x10.5 - ET +24
295/25/20
or
295/30/20

I recommend:

F: 20x9.5 ET25 with 255/30/20
R: 20x10.5 ET25 with 295/25/20

The fronts have really tight clearance with the fender liner when the wheels are turned and the slightly wider wheel will allow for a little more stretch to give you the needed clearance. If you want to go with 265 on the front and a 20" wheel, you will need 265/25/20, and that is very little sidewall. I am not even certain you can get a decent tire in that size. If you are willing to go with a 19" wheels which have so many more advantages in terms of drive/performance, your options open up a lot more.

[slicer]

Originally Posted by loklok1

F 20x9 - ET +24
265/30/20

R 20x10.5 - ET +24
295/25/20
or
295/30/20

Here is a thread that outlines a lot of different tire / wheel combinations that others have used (it's a sticky): http://www.m3post.com/forums/showthread.php?t=522139

The first thing I would say is that I have had 20" wheels on my M3 and I would not recommend it. Especially when the CHR is available in a 19" version. 20" wheels are nothing but a compromise (fewer tire options, fewer tire size options, reduced performance, more expensive, reduced ride quality, more susceptible to pot holes, etc.) and they don't look any better. In fact I think 20's look over sized on an M3. My recommended wheel and tire size for the BBS CH-R is the following:

19 x 9.5 et35
275/30/19 tires
(may need a 5 mm spacer with stock suspension. 15mm spacer required with KW coilovers because inner clearance is reduced)

19 x 10.5 et25
295/30/19 tires

Michelin PSS for street use. Yokohama AD08 for street / track use. The above tire sizes will require some negative camber to fit properly. If you don't want to add mild camber (less than 2.0 degrees) then I suggest 255/35/19 and 275/35/19 tires on the same wheels.

If you must get 20's then here are my thoughts.

Front: 245/30/20 will not rub but the side-wall height is ridiculously thin. I would never want to run that thin of a side wall. 255/30/20 will rub slightly at full lock due to the larger overall diameter (slightly larger than stock). 265/30/20 will absolutely rub due to the overall diameter. When I had 20's I ran 255/30/20's. If I were to do it again, I would buy 265/30/20's and deal with the rubbing. That gives you a little extra sidewall and Michelin PSS are available in that size. Michelin PSS are not available in 255/30/20. They are made in 245/30/20 but again I would never want a tire that thin. The reason I would stick with PSS is because they are the best performing tire available in 20". You are already making an unnecessary compromise by going with 20", you might as well get the best tires you can. Get ready to enjoy some rubbing...

Rear: 295/30/20 will absolutely not fit. Your options are 295/25/20, 305/25/20, 285/25/20, 285/30/20. The two sizes that I would consider are 305/25/20 or 285/30/20. I would want the widest 25-series tire possible to get a decent side-wall height. My #1 choice would be 285/30/20 which gives you the tallest side-wall and the best match for the 265/30/20 tire that I would suggest for the front. It's only a 20mm stagger which will maintain the OEM stagger while the wider rear option increases stagger and understeer.

Again, 20" wheels on the M3 are a big compromise without any gain IMO. The don't look right on the car.

[slicer]

Originally Posted by LarThaL

I recommend:

F: 20x9.5 ET25 with 255/30/20
R: 20x10.5 ET25 with 295/25/20

The fronts have really tight clearance with the fender liner when the wheels are turned and the slightly wider wheel will allow for a little more stretch to give you the needed clearance. If you want to go with 265 on the front and a 20" wheel, you will need 265/25/20, and that is very little sidewall. I am not even certain you can get a decent tire in that size. If you are willing to go with a 19" wheels which have so many more advantages in terms of drive/performance, your options open up a lot more.

Good advice but CH-R's are not available in 9.5" width.

[loklok1]

Thanks a bunch for your 2 cents Slicer and LarThaL

[loklok1]

I decide to go with the 20" because I added a front lip and my existing 19" looked smaller compare the before the lip added. Now thinking of it staying 19 is not a bad choice since tire options/size are so limited with this set up.

[loklok1]

I like the F265/30/20 and R285/30/20 and deal with the rub. Would you know if if 30 for the back is the max height or can I push it to R285/35/20?

[slicer]

Originally Posted by loklok1

I like the F265/30/20 and R285/30/20 and deal with the rub. Would you know if if 30 for the back is the max height or can I push it to R285/35/20?

The only other rear tire size option is 275/30/20 but the sidewall height is shorter than 285/30/20. 285/35/20 is far too tall.

[loklok1]

thanks for confirming Slicer

[SouthShoreM3]

OP not sure if you have made your decision yet, but I would go with the 19in BBS CHR. I also have 20s which are custom 3 piece and have been nothing but a complete compromise in performance. Yes they look great, but have been a pain and are nerve racking to drive. If you are really set on the CHR, I would recommend Dinan set of these. The offset is a little different and they come in 9.5 by 10.5. I run a 275/30 and 295/30 on these with the PSS and they are fantastic. I have the Dinan stage 3 suspension which does have a slight change in camber, but the ride quality, look and performance are greatly improved from the 3 piece 20s.

Go with the 19s and depending on the color of your car and the color you are looking for the gunmetal or titanium finish I think it's called is incredible.

Good luck!

[slicer]

Originally Posted by SouthShoreM3

OP not sure if you have made your decision yet, but I would go with the 19in BBS CHR. I also have 20s which are custom 3 piece and have been nothing but a complete compromise in performance. Yes they look great, but have been a pain and are nerve racking to drive. If you are really set on the CHR, I would recommend Dinan set of these. The offset is a little different and they come in 9.5 by 10.5. I run a 275/30 and 295/30 on these with the PSS and they are fantastic. I have the Dinan stage 3 suspension which does have a slight change in camber, but the ride quality, look and performance are greatly improved from the 3 piece 20s.

Go with the 19s and depending on the color of your car and the color you are looking for the gunmetal or titanium finish I think it's called is incredible.

Good luck!

FYI the Dinan version is the same as the regular version. The only difference is that Dinan puts their center caps on them and charges more. The 9.5" front is readily available. Tire rack sells them but they list them as 3-series rear fitment. Offsets are the same.