Goldeni245

I'm thinking about adding 17inch AMG rims with Bridgestone SO3's to my car to replace the standard 16inch 7spoke design. Will the heavier rims and tires slow my car and worsen performance? Or will it not be noticeable.

cdnclk320

I changed my stock rims for the new 17' AMG rims a few months ago (C32 AMG rims). They rock!! I have michelin all season sports - no complaints. You will not regret your purchase. Let me know what you decide.

Harris

I think the performance will not affect that much if you change from stock 16" to 17". But it will definitely be slower during acceleration when you change to 18" or above.

jswedberg

The key factor is weight, especially near the periphery.

The heavier the rim, the slower the wheel can accelerate (and decelerate)

Tire weight makes a difference, too.

I doubt you will be able to tell any difference - the guys who notice have 19" rims, etc.

Accord

Sending this one to Luke .

Ahmed

as far as changing from 16 to 17 is concerned, i dont think the performance will be sacrificed that much, maybe a little!

But, go for wider wheels at rear than front ( amg 5 spoke 7.5 front and 8.5 rear) and you'll love the handling of the car. It will actually feel faster and sportier!!

amazing fun!

go for it!

Goldeni245

how much performance is sacraficed...i mean...the 320 is already not all that powerful. Will it increase the 0-60 time and all that stuff etc if i add wheels that only 1 inch bigger?

stephens

If the rolling diameter is not changed, how can the wheel change effect performance.
IMO, there may be an increase in torque required to accelerate the wheel, based on an increase of mass at a given distance from the wheel centre, however this is something that would probably only be measurable on a freewheeling rim. The energy required to move the car would make any such change insignificant on a street car. Are you guys sure you are not confusing a change in overall wheel diameter, which is changing the effective gear ratio?

Richard Galing

Goldeni245
This site may be of help to you www.differentials.com/faqi.html click under calculator...providing with some tire specs, for comparative purposes you can determine your gains or loss of rpms @ a specific mph.

Regards
Richard

Goldeni245

lol, now i'm seriously confused...we need to speak in "simple" talk for me to understand.

Ahmed

when u change the diameter of the wheels, ur changing the total diameter and surface area of the tires too. Dont forget that ur adding on more weight! 17 inch alloys are heavier than 16 inchers.

Buellwinkle

You have two things going against you; 1) adding any weight that rotates increases drag on the motor and robs HP, this applies to pullies, driveshaft, wheels, tires, flywheel 2) if your tire diameter increase, which it will likely do, it will change your drive ratio and that will slow you down off the line.

I have never gone to larger wheels and tires without regretting it. Even my daughter wanted 17s on her car and I got them for her birthday but she hates the ride and power loss. Sure they look good but in my book, power rules. You will lose a noticible amount of power. Go to a local track and see what people put on their cars at the track. They swap their cool 18" rims for small 15" wheels with lightweight racing tires.

If current fashion trends dictate a larger rim, then shop for the lightest rim that appeals to you, put on the slimest rubber you can find and swap rear end gears for taller ratio to compensate for the change you made. I laugh when I see people spending $3,000-$5,000 on rims and cheap out on the rear end gears.

Goldeni245

maybe i should just stick with buying new tires, i wanted new rims purley for looks, but i guess deep down inside me, i don't really want that.

I think i will stay with the OEM 16in 7spoke design on my CLK, and replace the Continental tires with S03's.

Now the question is...will adding new tires affect the performance in a negative or positive way?! I know S03's are the best handling and performance tires there are out on the market right now. I mean...Will the tires add weight to my car therefore affecting power?

speedybenz

When I put the AMG Monoblocks off a C36 on my 1999, C280 sport I noticed right away that the car felt slower and the G-Tech Pro also showed about 0.3 to 0.4 secs slower from 0-60mph.

The stock 16x7" wheel and 205/55/16 wheel combo weighed 36 pounds.

The AMG wheel and 245/40/17 rear combo and the AMG wheel and 225/45/17 combo both weighed 45-46 pounds. Thats 10 to 11 lbs per wheel. And you can feel it.

Plus the suspension or shock has a decreased capacity to control the wheel movement now due to the increased weight.

But the car does corner better, but if I had just put 225/50/16 tires on my stock rims I am sure the car would have handled better also.

Jeff

stephens

I don't mean to doubt you guys as there seems to be empirical data to back your claims, but I am shocked at the difference that a change in wheel/tyre combo with no change in rolling diameter makes. The power required to spin (freewheeling) the wheel should be negligble. A .3-.4sec change in 0-60time is akin to a 50hp power increase.

Ahmed

oh enough said already!

just put on some 19 inchers and the car will look awsum. And then go and install a kleemans supercharger to compensate for the power loss!

hehe.....

Goldeni245

I don't have that type of money right now hehehe

quaz

I honestly don't think that you will notice anything but better looks and perhaps slightly better handling.

stephens

I think we can all agree with this!

WayneE

The reason people swap from pimpy 17", 18", 19", 20" wheels to 15" drag wheels is that the drag wheels allow a taller sidewall. The taller sidewall absorbs the shock of the launch better and provides better traction.

The fact that the entire setup is lighter is an added bonus.

I use 15" drag tires on a street car that I race (I run 17" wheels on the street). The primary reason I went to 15s is that I can get a 27" tall tire with a HUGE sidewall (car is lowered, so I can't run anything larger than 27s). The tall tire also gives me more contact patch.

For the original poster... get a wheel tire combo that has the same overall height as your original and try to keep the weights similiar. An easy formula for calculating tire height =

(width of tire in mm * aspect ratio as decimal)*2/25.4+wheel diameter

So for the rear wheels/tires on my SLK32 -

(245*.40)*2/25.4+17 = 24.72" tall stock rear wheel/tire combo

If I wanted to retain the stock height, I'd get an 18" wheel/tire that was right around that height...

(255*.35)*2/25.4+18 = 25.02" tall - this should be close enough to not throw off the speedo/ABS/TCS/etc.

So, if you're careful with the weight and keep the same overall height, you'll be fine. Enjoy the new wheels/tires