Hi everybody,
after long time of signing in the forum, and 8 months as owner of a T31 (with 60.000 + Km done in the aforementioned period) i decided that it's about time of buying new tires ... and upgrade a little...
Lifting the car is one of my favourites changes but as money is always an issue I ' d propably proceed on a later stage.
The 235/65/17 seems to provide a lift close to 20mm (as stated on other posts and nets size tire calculators) but some people state that increase of tire radius shouldn't exceed the 2.5% of the stock dimension (which for me is 225/60/17). In that case 225/65/17 would be also an option
Having in mind the following pro and cons i'd like to share your views upon the issue.
PRO
- Gain of ground clearance.
- More agressive aesthetic look.
- Lower engine REVs for maintaining the same speed with the stock tires (I'm not sure abbout that... )
CONS
- False speedometer readings (except it is automatically reajusted).
- False odometer readings.(except it is automatically reajusted).
- Increased fuel consumption. (should i expect an increase of more than 0.5 LTR/100 km?)
- Rubing on inside fenders on full lock.
- Saggy or uncoftable behaviour during turns?
Apart the above mentioned has anybody tried these suspension lift kits ? [b]http://www.spaccer.com/en_GB/
Thank you for your hospitallity ...
Waiting for your considerations....

Quote: More agressive aesthetic look

Wanna bet, no one sees the difference between 225 and 235.....?
Main problem is, too wide and high can sand (rubbing) your fenders at the inside occasionally...

Wanna bet, no one sees the difference between 225 and 235.....?
... I'm not sure about that ....
Rubbing fenders is an issue... so maybe 225/65/17 is the choice...
Anyone else to comment ...?

I have 235/65 R17 for summer and 225/65 R17 for winter (original size 215/60 R17)

* 235/65 will look a bit more badass than 225/65
* 235/65 will rub when turning full lock
* 235/65 will have worse fuel economy than 225/65 (it can depend on tread)
* 235/65 Speedometer is spot on (measured with GPS readings)

* 225/65 will not rub
* 225/65 seems to suit gearing better (6 speed auto)
* 225/65 will get better mpg


If you are not lifted, I suggest 225/65

I have the same (225) Yokohama Geolandar M/S (with snow-mark!) and they are (very)good without a question. Several here have em. Do not here any complaints yet...
Is a 4 season all weather + snow tire. Keep you from changing wheels twice a year...

i have 235/60/17 cooper at3.s

no rubbing great quiet ride and look great

Hard to say on fuel consumption. On the one hand, the wider footprint is likely to create more drag, so it should be worse, but on the other hand, the taller overall gearing ought to make it better - at least on the motorway. The trouble is, it will be very hard to get a true comparison because your odometer will show less miles covered on the bigger tyres so you'll think you're getting fewer MPG if you use the odometer to measure distance.

For me, I don't know what a T31 is like, but I've always felt that our T30 could do with a lower first gear when towing. Putting the bigger tyres on and increasing the gearing would only make that worse, and will give your clutch and dual mass flywheel a slightly harder time.

People have already mentioned rubbing etc.

Something nobody has yet said is that it might adversely affect your insurance premium (if you declare it) or your cover if you dont!

The other thing (which I think could be the most serious but don't know how far you can push these things) would be the potential adverse effect on the ABS and Electronic Stability Control. The new wheel and tyre combination will have a higher moment of inertia than the old one (because not only is it heavier, but the extra mass is mainly round the outside edge. When the car was developed, they (Nissan) will have optimised the "pulse time" of the ABS system - i,e, the time between the system realising that the wheel has locked, releasing it, and the wheel spinning back up to speed again. If, for example, on the orignal tyres, the wheel takes (say) half a second to get back up to speed when released, it is likely to take (say) 5% more time to do so with the bigger tyre on. As the ABS intervention continues, this slight mismatch in time is going to "snowball", so after a few dozen pulses, the wheel and ABS system could be completely out of phase with each other and your ABS is trying to stop the wheel when it's already stopped and release it when it's already turning. It goes without saying that you could potentially have a pretty big accident (and indeed, people have) in such circumstances. What I DON'T know, is whether the modest change that you're talking about would make that much difference, or whether you really need a huge change for that effect to become noticeable. (For example, the system would have to cope with over / udner inflated tyres (which wil lchange the gearing) and it would have to cope with snow chains (which would alter the inertia). I know there is lots of discussion amongst vehicle regulators around Europe on this topic though. The Germans (as you might imagine!) are ahead of the curve and you can only fit wheel and tyre combinations that have been homologated for your vehicle. Whether that rolls out round the rest of the EU remains to be seen.

A big thanks to all of you, your comments really did help me...
I' ll go for the 225/65/17 and look for a lift kit (pedders seems to be the right choice...)

What are people doing for a spare when going up in size?

tyre sealer and a compressor?

or has anyone put a taller van tyre onto the steel rim?

Hi

This is a handy link if you want to see the difference tyre sizes give you in speed accuracy

https://www.4x4tyres.co.uk/catalog/tyresizes

Regards
Mike