c32AMG-DTM

Agreed. If you don't know where you're starting (i.e. the stock wheel weight), it's hard to know if you're going in the right direction. For most instances, I would guess that going from stock, cast AMG 17" to cast 18" or 19" wheel from AMG or someone else, you're going to be adding weight and losing a slight bit of performance. If you're going from the stock, cast 17" to a forged 18" (or maybe even 19"), I'd guess that your likely trimming some unsprung weight (rotational unsprung weight at that!).

Another thing to consider, if you're looking to slap a BBK on your car, you're probably not going to have a choice - you'll have to at LEAST go up to an 18" wheel.

Fifth Ring

And the last word: There's more selection and better pricing on 17" performance tires. Although that advantage is diminishing.

Fifth Ring

TireRack carries the 17" double spokes and lists them at 26 lbs.

Not to get all "Dr. Science" but the effect on HP depends not just on total weight but on where the weight is located. So with two wheels of equal weight, the one with wider diameter is likely to require more HP to accelerate, and more braking force to stop.

ShawnC32

LOL! You guys sound like a recent Bronx Bunny Episode! Hardest part is figuring who's Teddy T. Nah,... just joking! I'm learnin' a whole lot of stuff from peeps who know a hellava lot more than me. That's a good thing, and I'm very grateful,... THANKS!

Took a gander at the C55 18" wheels yesterday. He wants $800 OBO for wheels and remaining rubber. Wheels were in perfect condition,... no curb rash no where. The rubber is just about done though. Probably could ride on them for the remainder of the summer, but that's about it. We're suppose to hook up today @ 3. Think I'll OBO $700 and see what happens.

How does 7 to 8 sound for what I'm describing? I figure if I can upgrade for less than a grand, I might as well jump at it. Especially after reading that some wheel/tires sets can cost as much as $2800. BTW, the wheels he has on his C55 now are just awesome, powder coat black 18". Just simply bad-a$$! I just got to acquire a taste for black wheels on black cars! I know I will.

amgmark

That is a killer deal if the wheels are in excellent condition and painted!! I don't think the 18" weigh much more than the 17's either and they are the same width.. My 18" SLK55 wheels are 26lbs front and 27lbs rear.

I don't like black wheels much either, but im sure you can get them polished or repainted for pretty cheap and it would still be a good deal IMO..

Good luck..

ShawnC32

Yeah, that's what I was thinking... GREAT DEAL. But I just wanted to make sure before shelling out my 8 bucks. I'm still going to offer him 7 and see if that OBO sticks. I've learned enough on this topic to understand the ins-n-outs these will have on my C32. But at 7 to 8 bucks,... I'll take the nominal hit in acceleration. Besides, I'm hearing that more rubber on the road has it's advantages as well (the rubber coming with these wheels are 235's in the front and 255's on the rears. That's a little wider than the stock C32 wheels. I believe we're at 225 & 245. In fact I know that's where we sit,... I just replaced my rubber last Xmas. The wheels are in perfect shape. I didn't see any rash on any of them. I've been told that they can bend and wobble though, but I don't know how to check for that. But I'll risk it I guess!

No,... the black wheels are the wheels on his car NOW. The stock C55 wheels are the wheels that were lurking in the back of his garage after being replaced by the black ones. The C55's are the ones he's sellin' and I'm buyin'. Can't remember their names or size (I think they're 19", can't see him spending that much money to stay at the same size),... just that they were black is what hit me in the face. Took some getting used to.

Besides, at this price, I'll still be able to afford the EvoSport kit & LSD. Everyone is telling me these upgrades would more than make up for any acceleration hit. So I think I'll be happy in the end. Now all I gotta do is find someone reputable in my area to do the install. Anybody wanna buy a set of C32 wheels? LOL!

rbaker

I weighed my C55's stock 18's when they were bare & found:
Front 18x7.5" = 24 1/2 lbs
Rear 18x8.5" = 25 1/2 lbs

This was using the shipping scale in my office, which is probably only accurate to 1/2 lb anyway.

ShawnC32

Got'em. Man are they nice. These things are identical to the ones that came on my C32. I spent several minutes looking for differences and there's none that really caught my eye. I'll wait 'till this weekend and try'em out and see how they feel and if I have any of the rubbing problems I hear everyone talking about. But there really shouldn't be any of that since the 32 is nothing but a 55 with a shorter nose and 6 vs an 8. They also track the same up front,... I checked that out in another one of this forum's threads. We landed on $750, so I'm happy.

Some new rubber and I can check off the first of several upgrades and mods I've planned for this car. Good feeling!

Thanks everyone for your feedback and advice.

FrankW

the flaw in your argument is that the stock 17 type-IV weights around 26lbs for 17" wheels. Those are without a doubt some heavy wheels. The type-IV 18" on the C55 and CLK55 as I recall are actually lighter. There are plenty of cast wheel that weights much less than the OEM 17 type-IV wheels. OZ ultraleggera, bbs RA, just to name a few.

my wheel weights 20 and 21lbs respectively. and they're certainly odd looking according to most of you said. lol

uweb

Fifth Ring;
With stock 17" rims
- I have used 235s front (twice), with uneven wear on the inside each set; just went back to 225s
- I have used stock 245s/rear, replaced them with 255s one go-around, followed by 265s (Mich Sports) and just went to my second set of 265s/rear (Dunlop F and R, because Michelins were not available, when I blew a tire on a trip to CA, replaced all 4 ...; luckily I had a spare/2002s didn't come with a spare!).

Wheel spin has been reduced noticeably with 265/40/17 compared with the 245s.

splinter

Your BBS wheels are wholly functional, and do indeed look sharp.

Only thing precluding their installation on my car is the fact that they (with decent tires) are almost equivalent to a mortgage payment.

ShawnC32

Yeah Frank,... who said your wheels are odd? And as I am quickly learning, we're prolly talking twice my mortgage payment. I wish I would even think of using the word "ALMOST".

Sorry if I said something offensive!

Shawn

PTE

I can confirm rbaker's findings . He is right on the money . I've been working on fitting M/T 275 - 40 - 17" Drag Radials under the rear my 03 CLK for the Oct 8th meet at MIR.. So far I've machined 8 MM off the hub on a Vertical Mill to move the offset inward. It is close everywhere!! Not a Job for the light hearted, Tire width at it's widest point , side wall is 10 & 7/8th".

Josh K

that's what I get for not paying attention lol

ShawnC32

Well, I swapped out my 5 year old 17" C32 wheels with my new, er recently purchased previously owned 18" C55 wheels. Drove several hours on them and they seem just fine. Like I said before, the rubber on the 18's aren't as blessed as the rubber on my 17's, but they're not bad to seriously effect the ride IMO. I tell you what, those 255 in the rear makes a noticeable difference when powering out of turns. And I THINK I'm sensing a little improvement in general handling. Also, even though the fronts are 225's just like on the my 17's, they still look a little wider. Prolly in my head. As far as acceleration, well my butt dyno isn't picking up anything drastic hit. So you guys were right on the money with that one. However, I no longer hear a chirp when going from 1st to 2nd like I routinely heard when stomping on it with the 17's. But if that's it,... then I'm happy. They definitely look better. Fills the wheel wells up a little better so I'm thinking his tire choice has increased my turning radius a little. Man, it's not a scratch on these things,... anywhere. Come summer's end, I'll be asking for tips on tire choices for these 18's. Thanks again folks!

Fifth Ring

The lack of a 1-2 chirp could be the added traction, not less acceleration.

ericpd

I'm thinking added traction too. However, she is turning more metal mass. I think you noticing increased control coming out of a curve under power is also a gift thanks to better traction and more rubber on the ground. 225 on a 18 can be wider than 225 on a 17, depends a lot on what your sidewall height (profile) number is. This number is actually relative. It's still confusing to me, but I had a similar question when buying my last set. My tire guy made it clear that what you sense can actually be reality.

Believe me, if you do those other mods you're talking about, the last think you'll notice is a performance hit caused by your wheel upgrade. Good luck!

AWDman

slight correction f1 wheels are 13" https://mbworld.org/forums/c32-amg-c55-amg-w203/178098-my-13-inch-wheel.html

a larger wheel places it's weight further away form rotational center thus requiring a higer moment in acceleration and decleleration. worse if it's heavier. any added weight also hurts unsprung mass and ability to wheel to follow undulations of the road.

the 18" wheel i recently test fitted in this thread https://mbworld.org/forums/c32-amg-c55-amg-w203/188692-track-day-325-a.html fitted with 285/30 tire has a OD slightly lower that 245-40 17s. just to reinforce points made earlier!

it's easy to calculate sidewall height-
width x aspect ratio.

Overall diameter also easy (in inches)
(width (mm) x aspect ratio x 2) / 25.4 plus rim diameter.

there could also be a variation in a given size from differing manufacturers.

FrankW

for the math challenged here's a easier way to figure everything out http://www.1010tires.com/TireSizeCalculator.asp