jl2

Hi

has anyone put wider tires on the stock 19" wheels on the W205 C63s? I have the forged titanium AMG wheels and want to put 255 / 35 / 19 in front and 275 / 35 / 19 in the rear. Any success stories?

thanks a lot

bra10j

I had read somewhere that the rear could go to 285/35/19 and I plan to do that at some stage. If I've worn out the fronts in the process then i'll widen there too.

looney100

Just check the specs on your new tire. They will state what rim sizes will work. Also, keep in mind that your speedo will be off slightly.

mddel

I have the standard 19s. I switched to winter performance 255/35 and 275/35 and they fit just fine. I don't think you can go wider in the front, but the rears might actually take 285s. I might try that when I switch back to summer tires.

bra10j

I use the following site to calculate the tire sizes and ensure that the speedo won't be too far out.


www.willtheyfit.com/


Standard fronts - 245/35/19
Standard rears - 265/35/19


Speedo correction for fronts;
255/35/19 : -1.06% (so it under reads)


Speedo correction for rears;
275/35/19 : -1.04% (so it under reads)
285/35/19 : -2.05% (so it under reads)

msd3075

You want to keep the ratio of tire diameter between front/rear the same as stock as not to upset any of the dynamic systems on the car (traction control, skid, etc).

From what I've seen (mostly on the "Specs" tab on Tire Rack), the stock rear wheels can handle 285s. Only problem is that to get fronts with the same ratio as stock you would need 265s, and all the tire spec sheets say that's too wide for the stock front wheels.

If it were me and I was looking for noticeably more grip, I'd go with a 255/275 setup with a high grip rubber compound (Pilot Sport Cup, Potenza RE 71).

jl2

cool, thanks for the replies. i am going to try 255s in the front and 275s in the rear. will update after the winter.

in the meantime i ordered Pirelli Sottozero Serie II tires in stock sizes for the 19 wheels for the winter. tirerack has them if anyone is also looking for winter tires (call directly bc they are not on the website).

theclutch

I believe the rear wheels are 19 x 9.5". Got a clue what the width of the front wheels are?

msd3075

Front wheels: 19" x 8.5"
Rear wheels: 19" x 9.5"

The stock 18" wheels on the non-S model are the same widths as well.

Sanch

I have the black 10 spoke wheels and am keen to get a similar set up. What tires did you opt for? - I'm keen on getting Pilot Super Sports on the little wider set up for better traction.

Any issues?

YICS NZ

my c63s is on the black muiltispoke 19inch with michelins 245 & 265s. judging from how these tires are stretched to fit onto the wheels, my guess is the front can go up to 255/35/19 (even 265s?) and rears upto 295/30/19 (they are the exact 26'' diameter each so wont upset neither the speedo nor the electronic system).
the michelin 265s aren't wide enough for the amount of torque from my c63S, and hopefully with the 295s I could push it a bit harder.

RDOCA

I think you are exactly correct with your recommendation here but I would caution the PS Cup tires are not for the street as on the wet they are not the best so PSS for a DD would be better.

CT-AMG

So, after reading 2 pages of suggestions, I still don't know how wide we can go on the fronts and the rears.

Is there a definitive answer to this to keep proper geometry with front and rear?

RDOCA

With the stock wheels that are 8 1/2 front and 9 1/2 rear, the fronts recommended to no larger than 255 and rear no larger than 285.
But if you don't want to change the ratio you do 255 and 275.
Others have not kept ratio the same and gone larger in the rear and some have used wider wheels to go large than this.

hls2013

I'm sure that the C63s at the AMG academy were running 255/285 Continentals. When I asked about I was told it was stock.

RDOCA

They are not stock on the Sedan. 245-265/19's are stock on the C63S

CT-AMG

RDOCA: What is the detrimental effect if you change the ratios? Does anyone know? If I decide to go up to 295's on the rear and keep 265's on the front, what will be the effect?

Based on all of the posts, is it agreed that the biggest we can go without changing ratios is 265/285?

Has no one gotten a 275 on the front? That would be ideal..275 front and 295 rears would be plenty big and still keep the ratios..

RDOCA

Since you have tracked yours with stock tires you could be the guinea pig
and try what you propose and tell us how they work for you.
I saw one that went to 305 30 20s rear if I remember correctly. ( king monkey??)
Any thing over 255 f and 285 r is not recommended by tire rack spec sheet for width but that does not keep ratio the same (I don't know how important that is) but you would think the AMG engineers would tune for the stock size.

JPMBenz

According to Tire Rack...255/275 will fit on a stock rim without any issues. Anything larger, front or rear, will be stretch and not safe.

RDOCA

sorta /kind of
There is a design rim width for a tire but there is also a range that is acceptable and on the front the 255 is acceptable and the rear you can go as high as 285 and still fall in that range. But by doing that the ratio changes from factory.

theclutch

What "ratio" are you referring to? Is it the overall diameter of the front vs. overall diameter of the rear ratio?

RDOCA

By going up 1 size in front and the same on the rears
I don't know just how much a problem this would cause by effecting the tune of the suspension the AMG designed in.

theclutch

Ahh... I see. I believe the key thing is the overall diameter front/rear should be the same compared to the original tires. Otherwise, you will have speedometer calibration issues.

However, since the tires would be wider front/rear, there would be more weight to "unsprung weight" and it WOULD affect overall handling of the car, not to mention that the car will be stickier through turns. With regards to the heavier front tires, I would assume that this would give a slightly slower steering response. However, will we mortals actually even feel it? I think there will be some here that can say they do. But with me having 20+ years of DE, I can't make that claim (and no, I don't suck).

I just want as wide a tire as I can get without rubbing on the rears.

SuperNik

Since March I've been running 255fr 275rr
Michelin cup 2's. No problems at all and a lot better traction/ front end grip. Rears are very close to needing change so I'm gonna try some 285's. I'll report back if there's any issues with regards to the ratio difference.

AlexZTuned

How many miles did you get out of the rears with the Cup 2's?