So the question is what’s the widest rear tyre you can fit on a Z32 with standard body work? Rolled arches are permitted. Who’s got them and what does it do for the traction?

 

I know I can fit 285s on my 9½JJ wheels, but will they then fit in the rear arches?

My 265s caught :( managed to sort it with a roll and some suspension tweaks, they rarely catch now. Oh and you wont accidentally spin them up in the dry. A little bit of +5mph tractive scrabble in second on kuhmo fairly good saloon tyres.

I have 275s on my 9.5" rears, but they'll be getting swapped out for 285s eventually.

 

I think Jaffa has the widest tyres on here on a stock body...the arches have been heavily rolled, but it's not a wide arch. I 'think' he has 305s on his.

Well first off it depends what offset your rear wheels have and whether you've got standard suspension

 

As with any zed it's always a compromise once you deviate from stock

 

I've got 285's on the rear of both our zeds The one with out coilovers no problem the with coilovers arches rolled

Well first off it depends what offset your rear wheels have and whether you've got standard suspension

 

That's a given. I think the guy just wants to know who has fitted the widest tyres; offset is inclusive of that. If you have rolled arches, then offset can be tweaked to match.

I have 275s on my 9.5" rears, but they'll be getting swapped out for 285s eventually.

 

I think Jaffa has the widest tyres on here on a stock body...the arches have been heavily rolled, but it's not a wide arch. I 'think' he has 305s on his.

 

is 285 on a 9.5j pushing your luck? I have 10j and will be fitting 285 on them was told that's the correct tyre to use and a 295 would then be pushing my luck a bit

No, but I wouldn't go wider than a 285 on a 9.5" wheel. It will give flat tyre wall. Mine aren't 'quite' flat enough and find I need some increased girth! The profile is only a 30 anyway, so they're not gonna roll on the rim to any extent. 285" is good on a 10" too. I'd jump to a 295 on a 10.5" though.

Pretty sure in yanky land they have squeezed an 11j under there without a wide arch.

I briefly had 370z wheels, 10j rears they were 295 tyres, didn't rub but I ideally need to roll the arches slightly.

 

Once I get some tyres / money for... They will be going back on.

No, but I wouldn't go wider than a 285 on a 9.5" wheel. It will give flat tyre wall. Mine aren't 'quite' flat enough and find I need some increased girth! The profile is only a 30 anyway, so they're not gonna roll on the rim to any extent. 285" is good on a 10" too. I'd jump to a 295 on a 10.5" though.

 

when I spoke to the tech at toyo he said a 285 on a 10j is about the max you want to go fitting a 295 would not get the most of the tyre. so if you fit a 285 on a 9.5 then maybe you would get the performance out of it but mite just look better

 

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I briefly had 370z wheels, 10j rears they were 295 tyres, didn't rub but I ideally need to roll the arches slightly.

 

Once I get some tyres / money for... They will be going back on.

did you get much tyre role having 295 on a 10j ?

when I spoke to the tech at toyo he said a 285 on a 10j is about the max you want to go fitting a 295 would not get the most of the tyre. so if you fit a 285 on a 9.5 then maybe you would get the performance out of it but mite just look better

 

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did you get much tyre role having 295 on a 10j ?

 

Your tech guy is probably used to fitting 255s on a 9.5" wheel. LOL. 285s is fine on a 9.5" I am going to 285 and if I had any doubt at all, I wouldn't

just looking at the charts says 285 is max for 10j and 275 max for 9.5

I had 285/30/19 on rear of mine with arches rolled.

Ages ago I spoke to an old guy who I worked with who was good with that sort of thing,

He reckons u can over tyre a car, he said u wont get the heat into them, and a thinner tyre could make your car handle better,

 

Is this true, and would you not be better with a better quality tyre say 255/265 35 18 on the rear...

 

I know nothing about tyres just wondering what the fuss is with going has big has possible,

So the general consensus is that 285s do fit but the arches may need rolling depending on the wheel offset.

 

Dan, I'm sure the T&RA say that 285s are OK with 9.5JJ. I'll have a look when I'm back in work in the morning.

 

 

 

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i have 285 35 18 on a tenj and standerd set up and they do not rub at all they look the tits in my opinon and fill the arch and look the nuts from the rear. dont think i would or could go 295 without rolling or setup work. as for spin. i can pull really hard in the wet without letting go as long as i dont dump the clutch. dont need to. loads of grip, toyo proxes

Right, I'm going to keep my eye on the bay for a pair of 285 40 17".

 

 

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Ages ago I spoke to an old guy who I worked with who was good with that sort of thing,

He reckons u can over tyre a car, he said u wont get the heat into them,

 

 

Oh really?

 

 

He has got a point. A really wide tyre will roll a lot more on a wheel than one that's ideal. 285 on a 9.5" is absolutely not a problem.

 

Perversely, shit like this is dangerous AND it looks complete ass.

 

I have pulled a few cars out of hedges on corners with strechies on. They are ok for show if not over stretched but some to go to far with them

Yes, in terms of sheer grip off the line a tyre to big for the rim will reduce the contact patch, similarly beyond a certain width it's rubber for rubber, the weight of the car over the contact patch becomes the limiting factor or the amount if grip exceedes the power than can be applied.

Becoming more complicated, for grip throughout the corners too much tyre throws the car off balance applying force to the wrong areas and decreasing the useful part of the contact area. Then moving into really fast driving, too much rubber may not allow the car to reach the effective heat range for grip.

The simple thought of whacking a tyre wider tan dawn French on gives you ultimate grip is actually pretty flawed.

Right, I'm going to keep my eye on the bay for a pair of 285 40 17".

 

 

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Just bear in mind that a 285/40-17 is over 5% larger/taller than the std 245/45-16 tyre. It will drop your revs/mile my 5%

So any gain you might make on cornering will be possibly negated by slower acceleraion thru yer whole run

Ages ago I spoke to an old guy who I worked with who was good with that sort of thing,

He reckons u can over tyre a car, he said u wont get the heat into them, and a thinner tyre could make your car handle better,

 

Is this true, and would you not be better with a better quality tyre say 255/265 35 18 on the rear...

 

I know nothing about tyres just wondering what the fuss is with going has big has possible,

 

I was thinking along the same lines Terry - more width is just cock-waving really.... Ask yourself, why do you need more width - exactly!! 255 or 265 is more than adequate; since the EU/US spec twin turbos handled perfectly well for Nissan back in the day with just 245s....

 

I'd go for 265 (sticking to 18 inch rims) and simply buy the absolute best quality tyres (like Goodyear/Conti/Michelin); rather than specify an outrageously larger size, but have to compromise on a mid-range spec tyre. And whilst I have no doubt that Falken/Khumo etc may be up to the job - I know how I like to drive sometimes and prefer to put my trust in the former....:wink:

 

Just my opinion though; each to their own!!

 

Richard:cool:

Just bear in mind that a 285/40-17 is over 5% larger/taller than the std 245/45-16 tyre. It will drop your revs/mile my 5%

So any gain you might make on cornering will be possibly negated by slower acceleraion thru yer whole run

 

And what Pete said too......:wink:

Just bear in mind that a 285/40-17 is over 5% larger/taller than the std 245/45-16 tyre. It will drop your revs/mile my 5%

So any gain you might make on cornering will be possibly negated by slower acceleraion thru yer whole run

 

Point taken, and I'm going to have to work the maths out on that, but will the added grip decrease your 64ft time sufficiently to overcome the 5% decrease in acceleration over the 1/4 mile? I've run with 255/45-17 in the past. Going to have to think some more.......

 

 

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Point taken, and I'm going to have to work the maths out on that, but will the added grip decrease your 64ft time sufficiently to overcome the 5% decrease in acceleration over the 1/4 mile? I've run with 255/45-17 in the past. Going to have to think some more.......

 

 

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And then there is the factor of "tread wear" number of the tyre compound to think about.

For equal sized tyres the softer the compound the more traction it will give...especially with pre warming/burnout

My 370 rears had 275/35/19 10 j out the factory so roughly 26.5" dia 10.9" width

 

 

But we're then fitted with 295/30/19 which actually reduces their dia to 26" and 11.6" width

 

 

My oe tyres were 25" dia 8.8" width

 

The tyres look good, apart from having no tread left... Not very forgiving on bumps though. Tbh there show wheels

 

My track tyres are going on the ebay specials 9j 255/35/18 close to oe dia but 10" wide, but it turns in my better then with either my oe or the 370 wheels

Edited May 14, 201411 yr by (adl) phoenix