wheels and tyres

[Alpine]

does any one know if the front and rear wheels (Design 90's) are the same size (ie. could i put the wheels and tyres on the front straight onto the rear, or would i have to swap the tyres only)

the reason i ask is because on the rear i have Pirelli P7000 225/50 ZR16 which are worn out

on the front are newish (fitted by previous owner) Goodyear Eagle 225/50 R16. But, i think they should be 205/55's on the front, according to the handbook

so, could i swap the wheels and tyres front to back, and get new 205/55's for the front?

does it matter that the Goodyears are R16's and not ZR16's?

hope this is not too confusing !!

thanks
[]

 

[Guest]

It's seems you have the wrong tyres on the front, they should be 205 / 55 ZR16 on 7J rims. The back are correct on 225 / 50 ZR16 on 8J rims. Why the previous owner put the wrong tyres on the front is anyone's guess. Since you need new tyres buy two new front ones.

 

[Alpine]

thanks

i thought that would be the best thing

The ones on the front (that i will put on the back) are R16's. You say i need ZR16's. Do you know what the Z stands for ?

cheers

 

[Fen]

Z is the maximum speed rating - I just Googled to find out what exact sustained speed Z is good for and I found conflicting results of 149 (lower than I thought) to 190 (higher than I thought). I had in mind it should be about 165mph for Z.

I expect you'll find the speed rating on the other tyres is at the end of the size info because they have to have a speed rating if they were ever road legal.

You can't just put the front wheel on the back because the fronts should be 7" wide and the rears should be 8" wide (although they would fit). You should see a difference if you look at them but to confirm, the width and offset are cast either side of the valve stem.

 

[hotblack944]

ORIGINAL: Alpine
does any one know if the front and rear wheels (Design 90's) are the same size

Fronts are 7J, rears 8J, unless you have M030, in which case fronts are 7.5J, rears 9J. Whatever, width will be stamped next to valve.

See section 14.4 Wheels here:

http://www.connact.com/~kgross/FAQ/944faq13.html

but also read this:

http://members.rennlist.org/951_racerx/WheelsFAQ-measurements.html

ORIGINAL: Alpine
the reason i ask is because on the rear i have Pirelli P7000 225/50 ZR16 which are worn out

I believe you can run 225x50R16 on 7J rims front and 245x45R16 on 8J rims rear if you just want new rears.

ORIGINAL: Alpine
so, could i swap the wheels and tyres front to back, and get new 205/55's for the front?

No.

ORIGINAL: Alpine
does it matter that the Goodyears are R16's and not ZR16's?

Z is speed rating:

P - 93 MPH
Q - 99 MPH
S - 112 MPH
T - 118 MPH
U - 124 MPH
H - 130 MPH
V - 149 MPH
W - 168 MPH
Y - 186 MPH
Z - 149+ MPH

HTH,

Jim.

 

[Alpine]

thanks very much

i'll have a look at the valve stems to check wheel size

i've just been on the pirelli and goodyear websites which confirms what you have said

the owners handbook for the car says i need ZR speed rated tyres which is +149mph. My tyres on rear (Pirelli P7000) are W rated, and on front (Goodyear Eagle NCT 5) are W rated also

since W speed is up to 168 mph (and since my S2 wont go that fast!) i assume that W rated tyres will be ok ??

My main reason for concern is i know that insurance companies will use any excuse to refuse cover if there is an accident/claim

 

[Guest]

ORIGINAL: Alpine

thanks very much

i'll have a look at the valve stems to check wheel size

i've just been on the pirelli and goodyear websites which confirms what you have said

the owners handbook for the car says i need ZR speed rated tyres which is +149mph. My tyres on rear (Pirelli P7000) are W rated, and on front (Goodyear Eagle NCT 5) are W rated also

since W speed is up to 168 mph (and since my S2 wont go that fast!) i assume that W rated tyres will be ok ??

My main reason for concern is i know that insurance companies will use any excuse to refuse cover if there is an accident/claim

Dont worry about W or Y rated tyres, the ZR was just a code that was for tyres over 149mph, the W and Y ratings have come out after the ZR rating and cover specific speeds. Any Z W or Y rated tyre will be ok for your S2

 

[Alpine]

[/quote]

Dont worry about W or Y rated tyres, the ZR was just a code that was for tyres over 149mph, the W and Y ratings have come out after the ZR rating and cover specific speeds. Any Z W or Y rated tyre will be ok for your S2


[/quote]

thanks for confirming that

which are the best tyre brands to go for? if i have pirelli on the rear, should i stick with that brand on the front?

 

[chrisr]

IMO provided the tyre is the same brand on the rear or the fronts then it doesnt make a great deal of difference if you have say 2 Pirelli's on the rears but 2 Dunlops on the front -I just woudnt have say 2 different brands on front/rears - always been a fan of Michelins -currently have Michelin Pro Sports all round on the S2 ( 17inch Cup's ) but acknowledge that there are tyres as good for quite a bit less .

 

[Guest]

ORIGINAL: Alpine

thanks for confirming that

which are the best tyre brands to go for? if i have pirelli on the rear, should i stick with that brand on the front?

I have Toyo T1-S on my turbo, they are pretty good, and not expensive. About £70 for your S2. Kuhmo make some good budget tyres too.

If you dont mind paying you cant go far wrong with the Pirelli's, or possibly Bridgstone SO-3.

The most you will have to pay i would think is about £100 a tyre for good quality ones

 

[carlmthompson]

Hello everyone,

New member, so give me a break when it goes wrong!

Wanted to coment on the post above.

Having owned a number of different cars in the past, I know that it's really important to keep the same brand of tyre front and rear wherever possible. My current other car (BMW - don't give me greif!) says it is imperitive that the same brand is used front and rear, as otherwise the stability and traction control will get confused (at least I don't have to worry about electronics in the 944!)

Although most of the time the tyre will out-perform the driver, in the wet, different tyres have very different grip levels. What this means is that if you put a tyre on the rear that has less wet performance than the fronts, then you all of a sudden have a bit of unwanted oversteer (i.e not the nice power kind!!)

It's fair to say the more well known (and of course expensive) brands of tyres have a better dry - wet grip balance.

My advice is to keep the same brand front and rear unless you intend to change the other two soon!

Hope this helps

 

[John Sims]

My advice is to keep the same brand front and rear unless you intend to change the other two soon!

A very fair comment Carl, and welcome to the forum.

I have some nasty cheap tyres on the back of Beaky - Big Mistake! They just don't inspire confidence. The sooner I can bleach them out the better. I previously had Continentals which I couldn't fault. These things, "Maxxis" I think they are called, seem noisier, more inclined to track and more susceptable to throttle changes during cornering. In the latter case I guess this means they have less latteral stabillity. [][:'(][]

 

[carlmthompson]

Yup,

Mine's come with some pretty new Continental Conti Sport Contacts front and rear.

As you say I can't fault them, but I'll be changing them next time for a more dry oriented tyre - it's a second car so I won't be using it in the wet that much! I'm up for suggestions if anybodies had any experience with road legal dry tyres (at some point in the next couple of years I want to do a track day or so, but want to get used to the car first!) I've been thinking about Yokohama AVS.

My other thought is to by a cheap set of spare alloys, and put those on for track days (a decent set of D90's can be had for less than £200 on e-bay).

Any ideas?

 

[John Sims]

My other thought is to by a cheap set of spare alloys, and put those on for track days (a decent set of D90's can be had for less than £200 on e-bay).

You could get a set of wheels with part worn tyres from Porscheapart, Jasmine or one of the other suppliers. They generally have sets of wheels with well scrubbed top end tyres for IRO £500.

 

[Fen]

Welcome along Carl. Don't take this personally, but...

I agree that all 4 tyres should be the same on something like your BMW where they are all the same size and the ABS will no doubt get upset by the subtle differences in rolling radius that different brands may have.

On many 944s however the tyres are different sizes front to rear and therefore might have different tread pattern or even construction although being nominally the same type. Add to that the fact that some 944s came with the same size all round, some came with 205s and 225s, some with 225s and 245s and the basically identical 968 had 225s and 255s and I don't think it makes much difference. What I would say is always use decent tyres (and I include Toyos or Kumhos in that) and keep the same type on the same axle but don't stress too much about keeping the same front to rear.

I once had Yoko AVS Sports on my car and they were fine, but they didn't last long and they have absolutely no rim protector.

Finally I have seen D90's given away for free on here, so don't pay anything like £200 for a set.

 

[carlmthompson]

Hi,

Rim protection may be an issue, so thanks for that (although I won't be doing alot of parking!) Was there a noticeable difference in grip levels in the dry?

As for front and rear tyres, I would still stick with the same make and model front and rear - some cars have wider tyres on the rear, others don't - Porsche designed their cars to balance with wider tyres on the rear (otherwise they would understeer like mad with smaller tyres on the front!)

I guess it's horses for courses then!

As for the BM, I don't think it's the ABS (if so the 944 has ABS so could go the same way?), but the traction and stability control that get's a bit flustered with different brands (and it has got different brands on at the mo - and it's a bugger in the wet with much less grip at the front!)

Finally, if anyone want's to give me a set of D90's for nowt, I'd be most gratefull!! The last set on e-bay went for £105, so I'm not expecting to pay much more than that really (but don't everyone be going outbidding me at the last minute!!!)

 

[Diver944]

My own personal view is that the 944 has such good natural balance that there is no need to throw away a mismatched pair that still has life left in them. Ideally I would want all four tyres to be the same type, but at the moment I have new Kuhmos on the rear of my Turbo and very old Pirellis on the front with 3mm tread left. Even on a very treachourous wet Donington day last week the balance was absolutely fine.

Actually I think those Pirellis are made of Bakelite because they were on the car when I got it 43,000 miles ago [] and that includes several wet trackdays and a trip to the Nurburgring. I'll miss them when I do finally have to replace them [] probably early next year.

I'll be getting Kuhmos to match the rears.

 

[Fen]

ORIGINAL: carlmthompson
Was there a noticeable difference in grip levels in the dry?

I only ever used them on the road, and I can't say I ever found the limits of their grip in the dry. The rears were 265/18 so I expect if they did let go it might have been quite quickly and tricky to catch.