OverBudget

I just replaced my rear tires (at 6,300) miles and the 275/35/18 fit with no problems.

If that is the case, why did MB put 255's on the car as stock equipment?

Any ideas?

Ron Scarboro

I honestly don't know because it is certain that the C63 has too little tire on the back. The car has less tire than an M3 and weighs more with much more torque available much earlier in the rev band.

I just ordered 245/35/19 fronts and 275/30/19 rears so I'm glad to know that 275's will definitively fit with no issues.

musk

Can you post some pix of the new tires? Thanks!

Carl Lassiter

W211 guys have been complaining of this years. I mean, 2003 E55 came with 516lb/ft and 265s out back, they never rectified this for the E63. E60 M5 comes with 285s stock. Heck, my friend's 2006 M3 with 333bhp came with 265s stock(performance pkg CS, reg E46 M3 came with 255).

SL55 MKB

I always thought that going 255 to 265 is OK but to 275..isnt the tyre too big for the rim ?!

dremorg

Ok. Soooo ....if 275's fit well for the rear, are any of you guys thinking about changing the width in the front? Would that make a positive difference in handling? Or are the front OEM tires wide enough? I guess it's the grip @ the rear that everyone is mainly concerned about.

Carl Lassiter

Nah, rim will hold it just fine. If it were just the rim in question then you'd be able to load up to 295s, probably more (not sure of rim width, but guessing at least 8.5")

hhughes1

18" x 9" rears

liquiddi

What's funny is the 275 is the best fitment for a 9 inch rim. It is really weird that MB put 255's and 265's on these cars. I'm trying to burn my off the rears so I can get some 275's in back.

paulGT3

It would be really interesting to hear the story. I am guessing they got caught with the issue of having to give more fender clearance or go to production with a 255.

deaguero

Never could get that ole beast to hookup well

PatSC23

BMW did the same thing with 255's on the e46 M3's on both the 18 and 19's...i wondered why they did that too

MHP

Most likely NVH, slightly worse fuel economy, and again as with the detune, they didn't want the pony outrunning any of the horses.

bigwheeler

The clearance issue was a problem when the vehicle was loaded. They either had to wider the rear fender or fit slimer tires. In this case, cost savings encouraged to use 255 tires.

mthis

i had in my bmw 545i 245/40/18 in front 18-8.5 in front
rear i had 275/35/18 18-9.0 rear this was stock set up.

as soon as i found out that the c63 had 8.5 in front and 9.0 in rear i did the same set up. i have my front tires stiting in my garage they are new lol.

now i have 265 m/t on the rear this is the best tire for people that like to take off hard. with stock c63 and m/t you wont spin at all of line at full blast. even power braking you wont spin.

SebringSilver

Would the stock 255 rear tires fit on the 8.5" front wheels?

scarbrtj

Andy, what size tires are you using? Pardon me if you said already.

clktoc63

I've wondered about this as well. I asked my MB Dealer years ago when I bought my first Mercedes and got his answer. His answer matched one I received from a guy working at a Chevrolet dealer too. Take it what it's worth, but supposedly they leave room in the wheel wheels as a regulation to accomodate tire chains.

It may be absurd or even completely inaccurate, but that's the story I was given.

Ron Scarboro

My guess is cost... Cost of larger tires, cost to make clearances appropriate, cost to retune the suspension to different wheels (track width), tires and stagger.

Cost (due to the exchange rate and competition) are why we don't have the 19" wheels and the folding mirrors.

Suspension set up is somewhat dependent upon stagger. So if you go to 275 rear you want to match the stagger (so I went to 245 in the front).

Not to contradict the above, but the tire manufactures I'm looking at typically call for a 9.5" rear as optimal for a 275 versus a 9" wheel for a 255. Interestingly, most want a 8.5" wheel for a 235, with the largest on a 8" wheel of 225.

EROD

Changing the tire width, i.e 255 to 275 and keeping the same profile, i.e 35 would result in a tire that is about .5in taller meaning the ride height would be raised by about .25in. I'm thinking of going with 275/30 so that the ride height is lowered by .25in instead of being raised. On front i'm thinking 245/35, resulting in about a .32in drop. Don't know how 30 and 35 profiles would affect ride and handling but i'd rather have a slightly lowered car than a slightly raised one. Anyone tried 255/35 in front with 275/30 in the rear? That would keep the original 20mm stagger and lower the car by about the same height both front and back. I got the numbers from this cool gee-whiz site below.

http://www.1010tires.com/TireSizeCal...?action=submit

ARC101

This is only in relation to the OD (outside diameter) of the tire. So think about a 1/4" less tire filling up the wheel gap instead how much it lowers the car. Most use these tools when going +1 or +2 rims. For example. If you had a 18" rim with a 50 series tire and moved to a 19" rim you would want the OD to match up close. It does effect speedo, odometer, wheel gap, turning, etc...

Might want to really think about this before spending the money on rubber...
30 are a rougher ride the 35's as there is less tire and they usually need more pressure to protect the rim.

MRAMG1

Please tell that to Ford that used a 7" rim with a 225 from the factory for about 8 years.

After my first set, I put 245's on a 7" rim, but that didn't work well on the road course.

It all depends on your application my friends. If you want to road race, you want to stay with the widest rim posialbe and the smaller tire recomended for it, aka a 245 on a 9" rim. This is to prevent tire roll over while corning. If drag racing is your thing, you can use a 275 on a 8.5" rim with no problem. By the way, I know the above is true and works as I have done it in several different sanctioned bodies. For a daily street car, I have always gone as far as possiable, without rubbing when FULLY loaded. Unlike racing, rubbing is NEVER a good thing for a street car.

See yeah

Air Marshall Eldritch

I'm confused. I have 8" wide rims that came with 235/45 tires. I thought I could go to 245 without pushing it. You are saying 225 max? Am I thinking in reverse?

Carl Lassiter

You can safely fit 245 width tires on an 8" rim. Go to 285 and you'll still be fine (unless huge cornering loads) but I'd say 265 would be the best compromise if you want to increase you grip/contact patch.

MRAMG1

Well the 245 on a 8" is completly fine.

A 285 on a 8"
NO tire manufacture would agree with this, and you would certainly be risking the tire coming off the rim bead if you do ANY hard corning. Besides, you would actually LOOSE grip as the tire would be balloning around like a drag slick, and would not be level across the tread width.
When in doubt I would HIGHLY recomend looking at tirerack.com spec sheet from the manufacturer. NEVER go under the minumum size rim for a daily driven street car. The track is different obviously my friend.

See yeah

PS: Here is the Goodyear GS-D3 spec
285/35ZR18
Load Index 97 = 1609lbs (730kg) per tire
Speed Rating “Y” = 186mph (300kph) 97Y SL Treadwear: 280
Traction: AA
Temperature: A280 AA A 1609 lbs.
51 psi
11/32"
30 lbs.
9.5-11" Rim size
10"
11.4"
9.7"
25.9"
807
Country of Origin "DE" = GERMANYDE

Or

285/40ZR17
Load Index 100 = 1764lbs (800kg) per tire
Speed Rating “Y” = 186mph (300kph) 100Y SL Treadwear: 280
Traction: AA
Temperature: A280 AA A 1764 lbs.
51 psi
10/32"
28 lbs.
9.5-11" Rim size
10"
11.3"
9.9"
26.1"
800
Country of Origin "US" = UNITED STATES OF AMERICAUS