Blake P

Time to play "double up and catch up"!

Mu9enx

or "lose and sell the benz".

nope!

govertime

Hey Guys,
I read the forum periodically and STFF before posting, in this case the various tire and wheel forums, however I can never get a good grasp on tires sizes so I'm hoping one of you experts out there can help.

I currently have these tires.

Falken Ziex Ze 512 255/35R18 - rear
Falken Ziex Ze 512 225/40R18 - front

http://www.falkentire.com/xhtml/tire...egory=1&tire=5

Rear Wheels - 18x9.5 (35et)
Car not lowered.

The fronts tires are pretty much new but my rears are just about shot. It seams the 512 has been replaced by the 912s. (http://www.falkentire.com/xhtml/tire...egory=1&tire=3

While there are still a few retailers offering the 512s I thought it might make more sense to "upgrade" to the newer improved 912s. However, it seems the 912s aren't offered in 255/35R18. The closest size they have according to the chart on the aforementioned web page I believe is 245/4018.

1. Will 245/4018 be OK considering my a) wheel size b) the size of the front tires (I'm not sure if they need to have the same/similar overall diameter)?
If not, what size would match the closest, should I go with another brand?
2. Does it make much of a difference having slightly different tread patterns on the front than back?

I appreciate your help fellas.

amdeutsch

You might be better off with a 265/35-18 if you can fit it. Its closer to the front in diameter than the 245/40-18

govertime

Thanks for the quick reply deutsch!

What is the negative impact of having different diameters?

Uneven wear?
Tracking/Feeling Issues?
Electronic Stability/Control Problems
?

e1000

Possivle negative effects:
- rubbing on fenders/suspension
- change in speedometer reading vs actual speed
- ESP issues

With that said, you want to stay within 2 or 3% of the original overall diameter. Although the widths are different, the overall diameter of the original tire sizes are very close as well.

jello

See http://www.1010tires.com/TireSizeCalculator.asp to determine the impact on tire size, revolutions, etc...

C230 Sport Coup

Tirerack posts specs of each tire and they're all slightly different.
Just put Sumi HRX3 or whatever...the Bridgestone's that are on there rubbed when new, but these in the same size, don't as they're a little bit smaller.

govertime

I've found the miata.net tire calc the best tool to use for size comparison but what it doesn't tell you is what the negative results of putting rear tires on with a larger diameter than the front, aside from the obvious like rubbing, speedo wrong, or not fitting the wheel itself. Mostly my concerns are about improper wear/feel/ or mostly the ESP/ECT going haywire.

So it looks like edgeracing.com has the 912s in 245/40 for $108 each or 265/35 for $140. I'm inclined to save the $32 per tire and go with the 245/40 18. Any opinions?

Blake P

I'm running 245/35/18 because I was rubbing the fender with 255/35/18. 40 series would have a taller sidewall and larger rolling diameter.

agjoshi

I just installed new wheels on my C coupe. They are 18x8 with 225/40/18 tires. But, I hear an extended clicking sound from both rear wheels when I drive at ~10km/h which turns into a ticking sound as I drive faster. Is my tire size wrong? I have seen people here put wider rear tires on same size or bigger rims. The offset of my rims is ET 35 which seems to be correct. Except for the rims, my car is bone stock.

Did anyone see this problem before?

jscavo

bolts maybe to long and touching the ebrake.

20FHK02

Yup. Very likely are the lug bolts being too long.

C230 Sport Coup

Long time no see around these parts! What you been up to?

Just put some Sumitomo HTR Z III (Max Performance Summer 225/45R17)
tires on the rear. So far so good.

Mu9enx

hey sportcoue, can you tell me if those sidewalls are rounder then the blocky kumho ecstas? i cna't tell and have weak depth perception, lol

agjoshi

Thanks jscavo and 20FHK02. Got back from mechanic. Lug bolts were hitting the e-brake like you said. Does anyone know the size of the stock lug bolts?

Mu9enx

hey guys,
im in the market for new tires, and based off sportcoupes reviews, i'm really looking at the sumitomos or fuzions. but here's the problem:

with the kumho's ecstas SPT, i'm running 225/40 18's front and 265/35 18's rear. due to that, i've been rubbing constantly and it's pissing me the hell off. so what tire sizes would you guys recommend, for any tire? should i do 255's in the rear instead? i just want the rubbing to go AWAY.

so any suggestions for good looks / less rub let me know! thanks in advance.

if it matters, i'm runing 8.5 and 9.5.

TruTaing

Along these lines: How does one know if a tire has rounded side walls? Do you just LOOK?

thanks!

Mu9enx

bump

benze-ply

bump since I'm looking for tires too.

i was looking at falken 452's and i'm still trying to get reviews from mercedes owners about them

someone suggested kumho ecstas asx - which on tirerack garnered pretty good reviews overall.

one more - nitto invo's.

anybody have these tires or have any additional info?

donmega23

I just put these on last week and have no complaints. They look good, have good grip, and do well on corners. It hasn't been too wet around here yet so haven't tried them in wet but I am sure they'll do good there too, at least with what I have read they do.
I have 18". 225/40 in the front and 255/35 in the back.
I guess one thing I could say is that the so called "rim protector" isn't that great. Either that or my rims are a little wide for them to be very effective. I have 8.5" in the front and 9.5" in the back. But well that doesn't matter. They still work and look good.

benze-ply

are you talking about the falken 452's?

donmega23

Yep sorry about that, I did mean the Falken 452s. There was a bit of rain this weekend too and I got to test them on wet roads and they did pretty good for me there as well.

ozoz

i just got my rear with bridgestone potenza re001 called adrenalin in australia ... it behave quite well in fact ... less bumpy then the falken fk-452 i have replaced ... its 245/40 r17 ... i think its not bad for its price a$280 each

benze-ply

excellent!

what are people's take on pirelli p-zero nero's (not all season M/S and not rosso), just plain nero? Most reviews i've seen are on M/S - even mixed into reviews on the 'plain' nero's. i've read tramlining?

if you've got 18's - tirerack's got a clearance thing going on.