[CAR]

Well the front brakes wore out - 38000 k! Guess what it cost? 760.00!!!!! #$*&!!! Don't tell me if you got yours done cheaper because I'll implode. (Touring) Actually tell me then I will go back and get some money back.

Anyway I need new tyres - I'm sick of the road noise from the Bridgstones - cost is a factor and the 17" 50 series are **** expensive. I'm asking for advice now rather than after the event - I'm thinking of 245 45 17" or 235 45 17" - the rolling diameter is not that far off the 50 series - am I making a mistake? Will there be any other problems? ABS etc?

I would really appreciate help here.

 

[davidm]

Guess what it cost? 760.00!!!!! #$*&!!! Don't tell me if you got yours done cheaper because I'll implode.

Buying the pads through the dealer/factory is always expensive ... no matter what car you have. From memory the S2000 front pads were about $450, and for a HSV R8 they are about $650. I actually thought that the 350Z pads for the Brembos were around $600 as I asked about it when I bought the car. Though, that was just for the parts.

On the other hand if you go after-market then you should be able to get something pretty good for around $200 a set.

...I'm thinking of 245 45 17" or 235 45 17" - the rolling diameter is not that far off the 50 series - am I making a mistake?

245/45/17 are a much better match to the 225/50/17. The 245/45/17s are only 0.6% smaller than the 225/50/17s which really is negligible as your tyre wear will make a greater difference.

On the other hand the 235/45/17s are 1.7% smaller than the 225/50/17s. That implies that your speedo will be showing about ~2% higher speed than it used to when traveling at the same speed as with the 225/45/17s. It's probably still not a big deal as that is 2kph at 100kph and 4kph at 200kph.

Will there be any other problems? ABS etc?

I don't foresee any.

 

[CAR]

Thanks David - actually I should have said the brakes were for disks and pads - I suppose I can live with it.

 

[mickyboy]

Basically, changing the overall tyre diameter away from standard is not a good approach to take, it may affect the operation of the ABS, Traction Control System and vdc (not on your model though).

However saying that, working out the potential change in rolling diameter that occurs when a tyre of a different size is fitted requires some calculations. You are lucky I have done them for you as I am alos planning to change tyre sizes on my car when the time comes.

A replacement tyre must retain an overall diameter within a maximum of 5% of the standard tyre's diameter - but the smaller the variation from standard, the better.

So based on what you asked:

* I am assuming you will be fitting the same size tyre all the way round, not running a staggered set-up as is the oem case.

If you run 245 45 17" the overall diameter is reduced. Front by .7% rear by 2.17%

If you run 235 45 17" the overall diameter also reduced F by 2% rear by 3.5%

Both are within the limits and shouldn't pose any problems (note shouldn't!).

cheers

 

[mickyboy]

Some more info that I found regarding tyres upgrades. If you are changing the standard tyres for ones with a lower profile and wider section this will ultimately change the shape of the contact patch of the tyre on the road.

Changing to the wider tyre will give a contact patch that is shorter fore/aft, but is wider.

The change in the shape of the contact patch likely to reduce ride comfort but, it does have it's advantages.

The wider, shorter contact patch resulting from fitting of a wider tyre gives cornering gains. That is what I am after!

There is alot more to it, but in a small nutshell.

So further, probably the best bet would be to go for the 245's alround.

cheers

 

[davidm]

One more thing - are the 17" rims wide enough to fit 245 rubber? That's the only possible problem I can think of.

 

[mickyboy]

oem 17" front 17 x7.5
rear 17 x 8

Should fit 245 rubber easily.

 

[davidm]

oem 17" front 17 x7.5

Thanks. Looks like the front might be a bit on the extreme side as the S03s list 7.5" as the minimum width:

245/145/17 Bridgestone S03

Still, it is within the acceptable range so it'll be OK.

 

[ky350]

245 rubber will just fit on the 7.5" front wheel. Pity Nissan didn't just put 8" wheels all around - they probably saved $50 per car by using the smaller front wheels!

I was wondering if putting 245 all around would affect handling if the smaller 7.5" wheels were put on the back and 8" wheels on the front (ie rotating wheels / tyres)???

 

[mickyboy]

That's a good question!

The rim width's are different, but fitting the same width tyre would then negate that. But, that makes me also think of the wheel offset.
I believe that they are different from front to rear. I have a set in my garage and will have a look tommorrow.

 

[mickyboy]

Ok. Checked the offset. FRONT is -30 REAR is -33

There will be no problems if you decide to run the same tyre size all round and rotate them every service interval.

This will give much better tyre life, and if you have suffered from the 'feathering', then keeping up the rotation should mean that you won't notice it anymore.

The one concern is the insurance company, they normally do not like changing tyre widths or profiles unless upgrading rims. It is an absurd policy but unfortunately it exists.

I strongly urge you to check with your insurer before proceeding!
Tyre specification (& condition) is normally the first thing the assessor checks when reporting back to the insurance company.

Cheers

 

[coatsie]

CAR

In your post #3 you mention the cost was for "disks and pads"?

Replacing pads I could live with, but replacing the "disks" (and I'm assuming here that you are talking about the "rotors") I would find totally unacceptable. Subject to normal driving conditions I would be totally p'ed off if I got anything less than 100,000Km out of a set of rotors.

Perhaps other members have replaced their rotors and, if so, you could be guided by their experience, but I reckon you must have a strong chance of a warranty claim. It just seems that something is wrong.

I certainly hope I get more than 40,000ks out of a set of rotors.

cheers
Coates

ps It could be that the rotors were machined (and given the price, this is more likely), but unless you completely ran out of pads and actually scored the rotors, I would still find issue with this.

 

[Duncan]

We've been through a set of pads and rotors front and rear in 30000klm.

It has done a couple of track days, but nothing over the top.

The main problem with the discs is they are not designed to be machined, they are very soft metal and the machine just cuts straight into them. Ni$$an designed them to be replaced never machined. $700 reasons why apparently

 

[coatsie]

uvgotabf'njokn!!

30,000ks and new rotors!!!? I wouldn't be happy. I'd be challenging Nissan on the basis that this is totally unreasonable relative to market expectations. Such performance is way out of wack compared to other performance cars. My experience:
Celica GT - 220,000ks Rotors not even machined
MR2 Turbo - 160,000ks Rotors not even machined
Cooper "S" (early model) - Done 3 Bathurst 1000's (1970, 1973 and 1975), plus 6 years ATCC and still running original rotors!!!
I'd be talking to Nissan Australia about their warranty.

cheers
Coatsie

 

[CAR]

Yes my rotors were totally worn out at 38000 (as were the pads) I did jump up and down but not too much - i'm used to my Mercedes which only gave about 30000 ks. The difference is the price - I could buy aftermarket rotors for about 50 bucks each. i'm certainly going to look out for a aftermarket source.

All of you that have not reached this stage have look at your disks - if you have any sort of a ridge on the edge you too will be shelling out 760 soon!!!

 

[ky350]

CAR - Approximately how deep in mm was your ridge???

38k for rotors is unbelievably fast wear considering you only used the OEM pads. Imagine if you went to a harder compound semi track / semi street pad - you'd be changing rotors every 20,000km then!!!!

 

[lionking]

i had my rear rotors machined by nissan - no problem - the nissan tech ok'd it and they did it under warranty.

as far as tyre sizes compatability - i just came across this site

http://www.chris-longhurst.com/carbibles/i...tyre_bible.html

 

[CAR]

The ridge was probably a couple of mms. Enough to feel or catch your fingernail on.

BTW dont touch if its hot!!! :doh: :doh:

 

[mickyboy]

A good link for when contemplating changing tyre sizes:

http://www.everythingcelica.com/tech/speedcalc.html

 

[ky350]

[/quote]


I'll check mine tomorrow morning and retain my fingerprint!!!