what are the widest tires being run on an R?

akchang

New Member
wondering how wide a tire can be fit under our arches standard? if they are rolled?

im thinking of cutting out the arches, adding fender flares and going even wider. 245-275 with 0 offset wheel.
 

Fast Guy

Moderators
Staff member
Why do you want tyres that wide?

I think the widest normally is about 225s, but only because noone has tried to fit extrememly wide tyres yet. The suspension strut will be your limiting factor.
 
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Russ'R

Guest
Fast Guy..

I beleive you are runing 225's on yours, I have oportunity to get 16/225/45, what modifications if any have you done to fit these please?

Cheers

Russ :-D
 

Fast Guy

Moderators
Staff member
I'm running 215/35/16s

I did run 225/40/16s before, they fitted with no mods (On a et33ish 7x16). You might have rubbing issues with the slightly larger diammetre of the 45 series.
 

akchang

New Member
Fast Guy said:
Why do you want tyres that wide?

I think the widest normally is about 225s, but only because noone has tried to fit extrememly wide tyres yet. The suspension strut will be your limiting factor.
im not a straight line guy at all. i love taking my R on winding roads, track use and autocross. i thought i might gain quite a bit more stability and traction in turns with a wider stance and more rubber to the ground. hopefully with 0 offset i shouldnt have any problems rubbing the strut.
 

paz

Active Member
I've seen an R of hugely fat drag tyres (couldn't tell you how wide though) and dropped right down on coilovers. The owner has had to chop about 2 inches off each of the arches and is having wide arches fitted to accomodate the tyres. His is being used for dragging only though from what I can gather, so there's no real handling advantage for him.

Paz
 
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Odin

Guest
I'm running 215x40x16 but I'm going to change back to 205's because I think the bigger tyres, Put to much strain on the transmission.

I feel its better to let the tyres loose some grip rather than break me gear casing, Also I think it handled better on the 205's personally.


Rob
 

campbellju

Moderators
Staff member
I've been interested in sourcing some 225/45/16 off another owner and he's been doing some tests as he didn't want to sell me some duff bits. With out some sub 30mm offset, extended wheel arches and some panel beating it doesn't look like they will fit too well for a road car.

This is funny because a lot of the B13 Sentra racers have fit the same wheels on essentially the same car. This might be because they don't have to use full lock on a race track?

When increasing your track through big wheels or spacers, watch out for dodgy handling which is the oppisite of what you are trying to achieve.

Quick explaination http://en.wikipedia.org/wiki/Ackermann_steering_geometry.

This is deliberately simplified but you should be able to see that the wider the track the more your 2 front wheels point in the wrong direction which casuses scrubbing and torque steer.
 

campbellju

Moderators
Staff member
Odin said:
I'm running 215x40x16 but I'm going to change back to 205's because I think the bigger tyres, Put to much strain on the transmission.

I feel its better to let the tyres loose some grip rather than break me gear casing, Also I think it handled better on the 205's personally.
215/40/16 comapred to 205/45/16 will put "marginally" less strain on your gearbox, will have "marginally" more sideways grip but "marginally" less braking/accelerating grip and for what its worth be "marginally" closer in diameter to OE.

BUT this all depends so much on your choice of tyre and even the same tyre in a different size can be produced differently so the rule book is really just a guide.

I was looking at a semi slick in a 205/45/16 vs a road tyre in a 215/40/16 but this boiled down to semi slick vs road tyre for what I do, the size is just noise.

Rob, having said all that, bigger profile tyres on your car might work better because you have such stiff springs your sidewalls become your only suspension.

IIRC, you used to run Toyo T1S, these have a soggy sidewall in any size but that might have been helping your ride. Even if you moved to T1R, they have a marginally stiffer sidewall. On my everyday car, the previous owner has some uber-sports Bridgestone S03's. They were hugely grippy but the said PO also ran them at around 28psi becasue they were uncomfortable on poor roads. Changing only the tyre to a more sports-touring orientated tyre, I can run a more motorway/response friendly 35psi.
 
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Odin

Guest
campbellju said:
IIRC, you used to run Toyo T1S

You have a good memory Jim :shock: , I can't remember what happened yesterday :shock: :oops: .

I know it was a long time ago now but from memory :oops: , I preferred the way the car drove on the F1's at Silverstone and castle coombe, Compared to the toyo's at Knockhill. But then again I was on the Gab susp at Silverstone and Castle coombe and coil overs at Knockhill :? .

But I think the smaller taller F1's and softer springs will be a good choice for road and track, Also the smaller tyre would be safer for a bit of drag racing ;-) .

I want to go out and have fun on track/drag not be the quickest their, My main concern is to make the car the best it can be on the road where it will be used mainly ;-) .


Rob
 
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pulsarboby

Guest
this tyre thread is a very very personal subject in terms of driver style and ability!

about 2 years ago i purchased an astra gte circuit car from a driver who was moving up to touring car, as he had won everything at the cars level in lma euro saloons!
the car was running 205.45.15 with yokohamas and full leda coilovers.

he told me his little trick with tyre pressures was to run 50 psi rear and 45 psi front (cold):shock:
this equates to an extra 7 or 8 psi more when the tyre is hot.
the method behind this madness was that the tyre on hard cornering would have virtually no lateral movement and would help immensely with understeer, as you would have maximum grip with tyre at that pressure!
now this worked for him (as his race positions proved), but when i took car on test at brands hatch i found that car had huge understeer on every bend, the car was drifting massively (although very controllable) but no good for putting in a quick lap time!
as soon as i dropped pressures to 36 the car instantly transformed with a lot higher cornering speeds, and more warning before breaking loose.
so i think it all comes down to what suits each individual driver.
and the type of track the car will be running on, whether tight n twisty or long sweeping bends! different tyres and widths will suit different driving styles and tracks!:-D
 
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campbellju

Moderators
Staff member
Rob the F1's seem to be an excellent choice in tyre tests at the moment, I'm hoping to get some on mine before Japfest.
 
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robinsongtir

Guest
235's will fit if you are running on some kind of coilover setup.I run 235/60/15's they fit no problems but you need to raise the car a fair bit to clear the standard arches.But I need my car to be as low as possible so some wide arches were needed to lower the car back down.




"I've seen an R of hugely fat drag tyres (couldn't tell you how wide though) and dropped right down on coilovers. The owner has had to chop about 2 inches off each of the arches and is having wide arches fitted to accomodate the tyres. His is being used for dragging only though from what I can gather, so there's no real handling advantage for him.

Paz"
 

paz

Active Member
Thats the puppy. Loved the look of it last time I saw it, can;t wait to see it finished. When are you planning on being done?

Paz
 

campbellju

Moderators
Staff member
robinsongtir said:
235's will fit if you are running on some kind of coilover setup.I run 235/60/15's they fit no problems but you need to raise the car a fair bit to clear the standard arches.But I need my car to be as low as possible so some wide arches were needed to lower the car back down

:shock::shock::shock: Blimey Pete, those wheels are mahoosive. Did you have to do all the things Paz said to make them fit?
 
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robinsongtir

Guest
no set time as to when its done when time and money dictates sadly.

I fitted the wheels and tyres on the car when I just had the coilovers on the car needed a fair bit of panelbeating mainly on the arch lip to fold them into miss the tyres could then get fulll lock no probs. The coilovers were adjusted to about half way up the strut I would say about up to the standard ride height level.

Then the real fun started LOL because of what I was wanting to acheive this was not acceptable major surgery was needed to lower the height of the shell significantly.
 

Keira

New Member
robinsongtir said:
major surgery was needed to lower the height of the shell significantly.
you saying you had reverse lippo suction and now look like rob ?????? :lol:
 
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robinsongtir

Guest
well the car has actually lost a little weight from its sides and gained a bit inside with the cage and bracing mods.
Rob must be on a mission to concentrate the weight of his car towards the front engine to aid traction over the front end if thats the case lol
 
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