merckx racer

Just got some very nice 17" OZ Allegeritas(anthracite) 60mm offset squared for my '02 NFR S to replace
some heavy 18" Axis wheels and I'm less than thrilled.
I weighed both wheels and tires and I went from the 18" to 17" and also saved about 5lbs. per wheel.

The car does seem to excellerate a bit quicker...rolls lighter and easier and also braking seems improved
but the car doesn't handle as well..it just seems to be a bit higher and it doesn't seem to have the grip
the 18" wheels had.
I'm on Sumi ZTR111 squared..brand new...225/45/17F and 255/40/17R.
I was running Sumis ZTR111 255/35/18 on rear and some other brand
225/40/18 on front.
It just seems the profile on the Sumis is veryyyyy high for 45's and 40's and I did see some other
tires like Michelins that seem to have a lower profile for the 45's and 40's...
I just have a lot of deflection now...does tread height vary from tire make to tire make?
thanks for any input!

ps...I LOVE the look of my car now....the OZ's..wow!

dc2-2-ap1

What is your air pressure set at? How many miles have you put on the tires? Most tires seem to be garbage in the first couple hundred miles.

Arro

OK, so the profile on the 17" tires IS taller than the 18"

For example on the rear:
18" tire sidewall height is .35 x 255 = 89.25mm
17" tire sidewall height is .40 x 255 = 102

That's 1/2" taller sidewall with makes sense because a 1/2" per side is = to 1" lost in wheel diameter.

Manga_Spawn

What are the wheel specs on both sets? I would bet you need to break in the tires first but if the wheel specs are vastly different that could effect handling as well.

s2000Junky

Your going to get more sidewall deflection/less precise handling from a tire if it has a larger sidewall compared to a shorter sidewall counterpart ie 18" to 17" if you are to maintain the same overall diameter. That's not to say you cant acquire a great handling stiff side walled 17" tire, it just means Your particular tire choice may not have been the best to stay with when increasing the sidewall height. I'm not sure what the sidewall construction is on this Sumitomo, but I do know that generally budget max summer tires are single ply construction or weak 2 ply, which does not compliment the s2k handling character at all. What im getting at is the tires poor construction may have been masked by the original shorter sidewall of the 18".

merckx racer

Yes!...that makes sooo much sense!
And I agree with others as well...the tires need a few miles..and I've already felt improvement after 200 miles
on them.
Talked to a guy at TireRack who told me some race teams buy tires from them and then actually
have some tread shaven off!
I agree with you S2000 junky..Sumis have been a bit exposed via the higher profile...and what I find odd
is looking at other 17" say 40 profile tires and their actual tread is just lower
than the Sumis..so?...I'm going to have to continue to wear these in
and in the future maybe a better tire for sure!
Thanks for all the responses!

Jim@tirerack

The other things is the tires you took off were probably worn so they would handle better at that point.

C4vettrn

I am in the market for wheels and tires. I have been looking mostly at 17's have 16's know. Curious how your ride quality changed between the two. I know the shorter sidewall will be stiffer but how much worse is it on a S2000. I live in Northern Indiana and our roads suck to say the least. I went from 17's to 18's on my Vette keeping overall diameter the same but also switched from OEM Bilstien to the Sport Bistiens at the same time and the ride was much harsher. Not sure if most of it was the sidewalls or shocks or equally both.

merckx racer

C4...going from 18's to 17's?...yes..the ride is a bit more plush!
But I'm still in an AP1 S2000 so it's not exactly a Caddy!