rubbing my rear end

[VR4Kaos]

ive swapped my rear wheels for my fronts as the fronts had better tyers and wanted the grip on the rear rather than the fronts but now when i turn a corner sharply or go around a round about i lil keenly im gettin a rubbin noise as if my wheels/tyers are catching the rear suspenion anybody got any idea why when this never happened before i did the change over "o" btw all tyers/wheels are of the same size :stars:

[VR4Kaos]

please don't say its my rear diff please please please

[miller]

are the tyres directional? if so are all the arrows (marks on sidewalls) pointing forwards?

[VR4Kaos]

nah mike they not directional also kept em to the same side aswell

[Roberto]

Any chance the wheels have a different off-set?

Otherthan that I'd swap them back and see if you can see any differences.

[VR4Kaos]

can't say i cheaked that Roberto but i very much doubt it altho im on my way to check i will post on here it if they are different aswell

[VR4Kaos]

just cheacked and they all the same offset

[elnevio]

Have you checked the offset number (i.e. the one that says ET+42, or similar)? I know this can sometimes be confused with the width of the rim (i.e. the part that says 7JJ, or similar).

[elnevio]

Although to add to that, I would be surprised if they are rubbing, given that I think the wheels are well within normal parameters (from your other thread)!


Does it only make the noise when you have an AYC light on? It could be the first sign that the AYC fluid needs changing. You can test this on a safe stretch of road at about 20 mph by weaving/wiggling side-to-side get the AYC lights to come on.

[VR4Kaos]

im off to take me kids thai boxing in a few mins so will test this out on way home Nev.
But i already know they light up on dash quite easyly which scare's me into thinking my diff is on its wat out please tell me i am wrong as this is likely to reduce a grown man to tears

[elnevio]

Depends when they come on, really. Some cars get the bars lighting up round fairly mild bends. But it could be due to any combination of factors, but they usually come on at the 'wrong times' due to things like uneven tyre wear, tyre pressures, tracking misaligned, etc.

When my fluid started to degrade, I would get the 'wailing banshee' on corners, but noticed it stopped as soon as the last AYC bar went out.

[VR4Kaos]

thank you Nev will put it to the test now they was comin on very easy which is why i wanted to swap my front tyers for the rears felt like a rear wheel drive in bends roundabouts and corners feels a lil weird at the mo but presume that is due to the change also gettin a lot of wheel wobble and shudder when braking again presume this is due to un balanced wheels so much affects from such a little change.

[Turbo_Steve]

Karl - have you checked the tyre pressure and that the wheels are bolted on properly?

AYC being oversensitive is usually a sign of a tyre\wheel problem rather than the diff going.

I think it's highly unlikely that changing the wheels over has "suddenly" revealed that the diff is failing. As Nev says, it's more likely that you've put grippier tyres on, chucked the car around like a loon to test them out, and subsequently finished off your diff fluid and need to change it.

[Wodjno]

What is the OFFset ? And how wide are the wheels ? And what tyres eg.. 215/45/17 ??


Cheers

Wodj

[VR4Kaos]

33847
215/45/17
just been for another drive and it really dose feel as tho the tyer is rubbing the rear arm thingy majig :upsidedow

[elnevio]

+48 is the offset. +48 is possibly too high. In fact, I think it might be higher than stock.

The higher the offset goes, the further into the car the wheel goes.

Are the tyres different makes? (I think you've mentioned before that they are)

Different makes of the same size tyres will often be a few mm different in actual mounted width, due to the differing construction techniques, sidewall thickness, etc., etc.

[Roberto]

due to the differing construction techniques, sidewall thickness, etc., etc.


Rim protector on the tire aswell can add a few mm's.

[VR4Kaos]

really very intresting and educational thought the +offset was further out of the car
also yes you are right in the different tyers toyo proxy's and arrow guard and i can see what you mean by the differant constuction they have as they deffo do think i will swap em back over tomorrow explains why the previous owner had the better tyers on the fronts thank you everyone for the input/advise much appretated

[elnevio]

Rim protector on the tire aswell can add a few mm's.
I'll file that under "etc., etc."!! :D

Yes, if the tyres have a XL load rating, they often include a rim protector. Which don't do a very good job of protecting the rim, TBH! :d

[Louis]

more likely to be tyre pressures. if they were ok before, you may have done something like bend a brake backing plate.
Try swapping them back again to see if it is still there.

[bradc]

215/45/17 17x7 48mm is the wrong size in about 3 different ways, but ignoring that... a 235/45/17 tyre on a 38mm offset wheel will be sticking in as far as the combo that Karl has, however a 235/45 tyre is quite a bit taller, so I think it should be fine and should not be rubbing on the suspension as it curves in the further up you go.

Obviously it isn't too hard to physically check this!

[VR4Kaos]

wrong in three way's please tell me more this is how i bought the car btw
also i have physically cheaked the space behind the wheel space and could only just stick my finger in the space in beween the wheel and arm thingymajiggy thing

[bradc]

215/45/17 is too small, 17x7 is too small, and 48mm offset is wrong.

Aftermarket setups which are less than 225/45/17, 17x8 and have a higher offset than 40mm are wrong. Simple as that!

[VR4Kaos]

would you say that is the perfect fittment brad ?
or would a - offset be better
or a 18/8 or 8.5

[Wodjno]

33847
215/45/17
just been for another drive and it really dose feel as tho the tyer is rubbing the rear arm thingy majig :upsidedow

as i suspected.. 48mm offset is way to much.. I am on a 45mm on 225/40/18's.. I have around 2mm clearance on the suspension arm when the tyres are new..

48mm i would say will make the tyre touch the arm straight away even with the smaller tyres you have on /yes Were those tyres and wheels on the car when you got it ? I think maybe they was, so the wear on the rear tyres had already taken place.. And only when you swapped fronts to rear, the rubbing was apprarent to yourself. There is alot more clearance to the front suspension arms..

Cheers

Wodj

[VR4Kaos]

wow 2mm don't yours rub or it becouse there is more clearance the bigger you go

[Wodjno]

wow 2mm don't yours rub or it becouse there is more clearance the bigger you go

How can i rub ? It's 2mm away :-) and with 18's on a 40 profile
@ 35psi. there ain't much movement :)

I would suggest getting some 2 or 3mm spacers for the short term for the rears.. Longterm is to change the wheel and tyre set up..

[bradc]

Just get 15mm bolt on spacer, this will see the outer edge of the tyre in roughly the right place

[VR4Kaos]

[QUOTE=Wodjno]How can i rub ? It's 2mm away :-) and with 18's on a 40 profile
@ 35psi. there ain't much movement :)

errrrr now im absalultly lost i have more than 2mm 5-10mm id say

[bradc]

Might be something else making the noise

[Wodjno]

[QUOTE=Wodjno]How can i rub ? It's 2mm away :-) and with 18's on a 40 profile
@ 35psi. there ain't much movement :)

errrrr now im absalultly lost i have more than 2mm 5-10mm id say

At the top inside corner ?

[bradc]

5 to 10mm sounds about right to me based on his tyre size and offset

[VR4Kaos]

yes inbetween wheel and arm,
ive just be out and measured thegap and it is 15mm at least
i am on stock suspenion tho if that make's any difference ?

[Wodjno]

5 to 10mm sounds about right to me based on his tyre size and offset

Approx 6mm vertically lower and 5mm narrow on the inside edge /yes

[Wodjno]

yes inbetween wheel and arm,
ive just be out and measured thegap and it is 15mm at least
i am on stock suspenion tho if that make's any difference ?

No that doesn't make any difference..

You nearby to any other members ?

[VR4Kaos]

not that im aware of mate

[Wodjno]

You haven't knocked the protective shielding on the rear disc have you ?
So it's very close to the disc ? And under hard cornering the disc is moving a fraction of a mm and graunching on the shield ??

[VR4Kaos]

You haven't knocked the protective shielding on the rear disc have you ?
So it's very close to the disc ? And under hard cornering the disc is moving a fraction of a mm and graunching on the shield ??
this could be a possabilty mate i can't say i did notice this sheild tho mate to be honest i also did change my rear pads on the same day so the raises that possabilty loads init i guess the wheel will need to come off tomorrow to see all this was done on the day of my wheel spoke alinement
http://www.clubvr4.com/forum/showthread.php?t=47809
post 20 by AlanDITD

[Wodjno]

this could be a possabilty mate i can't say i did notice this sheild tho mate to be honest i also did change my rear pads on the same day so the raises that possabilty loads init i guess the wheel will need to come off tomorrow to see all this was done on the day of my wheel spoke alinement
http://www.clubvr4.com/forum/showthread.php?t=47809
post 20 by AlanDITD

Well it wouldn't be the 1st time i had bent the shield towards the disc :sad3:
But normally when changing the disc aswell.

Look forward to some daylight then /yes :zzz:

[VR4Kaos]

defo mate thank you for all your advice mate much appreited :chugchug:

[VR4Kaos]

ya not goin unnoticed Brad, Steve nor any one else thanks all :chugchug: :chugchug: :chugchug: :chugchug: :chugchug: :chugchug:

[Wodjno]

defo mate thank you for all your advice mate much appreited :chugchug:

No Worries ..

But much easier to diagnose in the flesh /yes Than to misdiagnose over the Net :whistle:

[VR4Kaos]

too tru also much easyer having such a helpful club init mate

[Turbo_Steve]

i also did change my rear pads on the same day

I think that may possibly be a very very big clue :D :D :D


Sorry we can't be of more help, Karl, but as Wodj quite correctly says playing "guess that noise" over the net is like trying to pin the tail on the donkey. It's possible, but error prone.

[Wodjno]

Any Update on this Karl /Hmmm

[VR4Kaos]

sorry mate no at least not as yet mate not had chance to be honest :( but will update soon as i work out what it is

[VR4Kaos]

been investergating this issue today to no avail but am sure its rubbing on the arm im gonna get some chalk and see if thats were it is rubbing its not the sheild ive ensured that there is clearance all the way around the disc
to be continued......lol

[Wodjno]

If the tyre is as far as you say it is away!
Then it's not possible for it to touch the ARM..

[VR4Kaos]

If the tyre is as far as you say it is away!
Then it's not possible for it to touch the ARM..
as it happens it not rubbing the arm so it defo coming from somewhere eles :( :bigcry: :bigcry: :bigcry: :bigcry:

[Roberto]

Any chance it's not rubbing at all, but a wheel bearing on the way out?

[John TheAntique]

I'll go with Turbo-Steve on this but I take it you have checked the hand brake's not binding?

[The Vee]

Please don't take this the wrong way - but it does happen.............are you sure you have the brake pads the right way round?

[Kieran]

215/45/17 is too small, 17x7 is too small, and 48mm offset is wrong.

Aftermarket setups which are less than 225/45/17, 17x8 and have a higher offset than 40mm are wrong. Simple as that!

Erm....

How exactly is 215/45R17 a wrong tyre size, given the stock size is 205/55R16?

That's a 1% tolerance in overall rolling diameter and well within guidelines.

Also - How is a wheel size of 17x7 Too small?

[aboo]

Erm....

How exactly is 215/45R17 a wrong tyre size, given the stock size is 205/55R16?

That's a 1% tolerance in overall rolling diameter and well within guidelines.

Also - How is a wheel size of 17x7 Too small?I would like to know the answer to this as well cause I'm running 17x7. 215/45/17

Its the wrong size as simple as that is'nt really an answer.

[Wodjno]

I would like to know the answer to this as well cause I'm running 17x7. 215/45/17

Its the wrong size as simple as that is'nt really an answer.

As Kieran says.. Those Tyres are correct /yes

Use this little gadget: http://www.miata.net/garage/tirecalc.html

There are more aesthetically pleasing and complicated versions out there on the web /yes But i find this 1 just tells you it how it is :D



Cheers

Wodj

PS.. I run 225/40/18's which if you stick in to the tyre calc you will see is correct also..

PS.. 2... Re: The answer, Its the wrong size as simple as that is'nt really an answer.

Well thats just thats just Brad being Brad.. /pan

[bradc]

205/55/16 has a rolling circumference of 1985mm, 215/45/17 is only 1964mm which is 21mm less. 225/45/17 is 1992mm which is only 7mm away, therefore closer.

A car with 205/55/16 tyres will have a slightly optimistic reading on the speedo, at about 100kmh indicated you'll only be doing 96kmh or so. 215/45/17's will make this worse! 225/45/17 will make it a bit better and closer to being accurate.

215/45/17's will make the top of the wheel arch to top of the tyre gap 5mm bigger than 225/45/17 while at the same time making the bottom of the chassis to road gap about 5mm less! So you have more of a need to lower the car to get rid of the massive wheel arch gap and end up with a car that is a lot lot closer to the road!

205/55/16's have a standard load rating of 91 (XL is 94)
215/45/17's have a standard load rating of 87 (XL is 91)
225/45/17's have a standard load rating of 91 (XL is 94)
We will all agree that VR-4's are a heavy car and with the stock wheel alignment of near 0 camber the outer side wall is going to get hammered! I also question if insurance companies or the police would like people running a lower load rating than stock! For what it is worth, a rating of 87 is 545kg which is above what some cars will have on the front corners with two people in the car. Do a search on corner weights and you'll find most cars are around 500kg at each front tyre without people in the car. Put it into a corner and watch the sidewalls collapse! The 91 rating is worth 615kg. The 94 rating is worth 670kg and is clearly the best way to go. EVO 8/9's come with tyres rated at 655kg and those are lighter than VR-4's by around 100kg. Makes you think and wonder.

The 225's will have a taller sidewall of course which will typically reduce road noise which is something VR-4's are a bit bad with, definitely a weak point! Comfort will also be improved with a taller sidewall.

225's are of course wider than 215's which will of course offer more grip! Also some of the newest tyres aren't coming in 215/45/17 any more, witness the Goodyear F1 Asym who's smallest size is 225/45/17 XL with a 94 load rating.

Finally, 17x7's are wrong because you can only really run 215 tyres on them! The recommended wheel with for 225/45/17 is 7.5". Sure you can run 7" wheels with them but they will be a bit floaty and soft, moving about on the sidewalls. 215's are designed for 7" wheels, but as above, 215 is the wrong size in the first place!

Another point I just thought of, facelifts are 225/50/16 standard, why would you want to run skinnier tyres than stock? It simply seems to be an absurd idea to me!

Again, anything less than 225/45/17 on a 17x7.5" wheel is simply wrong. Ideally though an 8" wide wheel is better though, the sidewall will be nice and taught and it is easy to find 8" wide wheels suitable for a VR-4, just look for any stock EVO 7-9 wheel!

[Louis]

If it wasn't there before, try changing the wheels back the way they wer.
If the noise is still there when changed back to the way they were before the noise, then it's something that happened when doing the brakes:
trapped stone
pads rubbing on discs,(new ones being thicker)
bent backing plate
handbrake pads binding
twisted brake flexi line

I amd running 17 x 8 evo wheels with 235/45/17 tyres and have never had a rubbing prob!

it's unlikely a wheel bearing has just started making a noise just after changing the brakes!!

Did you push the pistons back into the calipers when fitting the new pads, or did you have trouble getting them in?, I am sure it is something easy to sort.

[Kieran]

Umm... Brad... I need to call you on that last post.



A car with 205/55/16 tyres will have a slightly optimistic reading on the speedo, at about 100kmh indicated you'll only be doing 96kmh or so.

How, given that this is the factory size? How can the stock rim size be 4% out from the factory?


205/55/16 has a rolling circumference of 1985mm, 215/45/17 is only 1964mm which is 21mm less. 225/45/17 is 1992mm which is only 7mm away, therefore closer.

No argument with those figures - However.. You're still only talking a 1% difference. Let me put some perspective on that. At 60mph, a 215/45R17 tyre will be indicating 59.4mph (to use the absolute figure, relative to the stock 205/55R16 size). A 225/45R17 tyre will read 60.2mph. My point is, the overall wheel diameter is close enough to be insignificant.


215/45/17's will make the top of the wheel arch to top of the tyre gap 5mm bigger than 225/45/17 while at the same time making the bottom of the chassis to road gap about 5mm less! So you have more of a need to lower the car to get rid of the massive wheel arch gap and end up with a car that is a lot lot closer to the road!

That's just utter nonsense. You can get a 5mm difference in road gap/arch clearance from a set of new vs worn tyres. Again... Insignificant.


205/55/16's have a standard load rating of 91 (XL is 94)
215/45/17's have a standard load rating of 87 (XL is 91)
225/45/17's have a standard load rating of 91 (XL is 94)


Erm... Two things - where do you get the 'Standard' load rating from? As far as I'm aware, tyres are produced with a given load index, but you can specify XL (Extra load) or choose a different model of tyre with an appropriate load index. I take your point that Load index is important, but the way you've worded that suggests that those are the *only* load ratings available.

It's also worth pointing out that Ariadne had her original tyre sticker on the B-Pillar, and the load index required was 89.


We will all agree that VR-4's are a heavy car and with the stock wheel alignment of near 0 camber the outer side wall is going to get hammered! I also question if insurance companies or the police would like people running a lower load rating than stock!

But again - This is a case of choosing the correct sized tyre with an appropriate load rating for the vehicle. I agree that it's important to do so, but again - Tyre size alone doesn't restrict you to one load index only.


The 94 rating is worth 670kg and is clearly the best way to go.
By what metrics? Sure - it's the strongest side-wall. But that's not the only criteria by which to judge. Provided the rating is within the specifications of the vehicle, there's no issue.



The 225's will have a taller sidewall of course which will typically reduce road noise which is something VR-4's are a bit bad with, definitely a weak point! Comfort will also be improved with a taller sidewall.

How does a taller sidewall reduce road noise? I thought that was a question of tread design, wheel width, etc. I agree that comfort will be better with a taller sidewall, but then if that's the priority, you need to stick to the stock rims - That's why I didn't change to bigger wheels.


225's are of course wider than 215's which will of course offer more grip!

On a sweeping, perfectly smooth bend - Yes.
However, there's more to consider. Wider tyres are more prone to aquaplaning. Not good for grip and/or braking distances in the wet. I think I'm also right in saying that wider tyres can tramline more over bumps?

But again - we're not talking huge differences here.


Also some of the newest tyres aren't coming in 215/45/17 any more,...

Really? Hmmm. I'll check on that.


Finally, 17x7's are wrong because you can only really run 215 tyres on them!..... as above, 215 is the wrong size in the first place!

You know, you're getting as militant about wheel sizes are you are about autoboxes.../pan




Another point I just thought of, facelifts are 225/50/16 standard, why would you want to run skinnier tyres than stock? It simply seems to be an absurd idea to me!

We're talking about a prefacelift car here Brad....



Again, anything less than 225/45/17 on a 17x7.5" wheel is simply wrong.
:vulcan:
Hmmm. Just a second. I need to go and sue Mitsubishi for selling the VR-4 and the V6 Sport... And in fact every other sodding model of 8G, 7G, 6G et.al. with the wrong size tyres! I could have died horribly every journey! Christ, it's almost a relief that I've not finished the Yellow Peril... I hate to think what'd happen if I took that out with it's 165x13 steels of retro on! I'd probably have exploded in a ball of fire before I'd left the driveway(!). I know you're referring to just 225s on a 7.5 rim, but you see what I'm getting at. There's nothing wrong with 215/45R17s on a VR4 provided they've got the appropriate speed and load ratings.

[bradc]

How, given that this is the factory size? How can the stock rim size be 4% out from the factory?


Most cars have optimistic speedo's. Witness: http://www.google.co.nz/search?q=optimistic+stock+speedo&rls=com.microsoft:en-nz&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1&redir_esc=&ei=cvzLS_b_M5Dc7APi3rj9Ag

I can't beleive Kieran that you've never known that?



No argument with those figures - However.. You're still only talking a 1% difference. Let me put some perspective on that. At 60mph, a 215/45R17 tyre will be indicating 59.4mph (to use the absolute figure, relative to the stock 205/55R16 size). A 225/45R17 tyre will read 60.2mph. My point is, the overall wheel diameter is close enough to be insignificant.

hat's just utter nonsense. You can get a 5mm difference in road gap/arch clearance from a set of new vs worn tyres. Again... Insignificant.


I'll accept it is insignificant, but a 225/45/17 near the end of it's life is going to be closer to the stock 205/55/16 than what a 215/45/17 will be!



Erm... Two things - where do you get the 'Standard' load rating from? As far as I'm aware, tyres are produced with a given load index, but you can specify XL (Extra load) or choose a different model of tyre with an appropriate load index. I take your point that Load index is important, but the way you've worded that suggests that those are the *only* load ratings available.


Generally tyres in 225/45/17 will all be 91 or 94. If you go to a website like tirerack.com and look at all of the tyres in a specific size, over 80% of them (even over different brands) will have matching standard and XL ratings. For example in the 225/45/17 size on tirerack.com there was 1 on the first two pages that wasn't either 91 or 94. I will accept that yes, you can get a 215/45/17 in 91 which is stock, but don't you want better than stock?




By what metrics? Sure - it's the strongest side-wall. But that's not the only criteria by which to judge. Provided the rating is within the specifications of the vehicle, there's no issue.


I know you're smart enough to understand the massive cornering forces at work, witness: http://www.autozine.org/technical_school/handling/tech_handling_3.htm

Even if you halved those weight transfer figures - unlikely though as a Boxster will have a lower CoG than a Legnum! You can imagine that a VR-4 with a static weight of around 450 to 500kg on each front wheel could easily be in the region of 600 to 700kg of weight on the outer front tyre in a corner. This amount of transfer is going to be worse on a stock car, just the type that is going to have undersized wheels that have a low load rating. Ironically the people with wide tyres will probably also have at the least stiffer springs than stock, and possibly coil overs and uprated anti roll bars to reduce the amount of weight transfer!



How does a taller sidewall reduce road noise? I thought that was a question of tread design, wheel width, etc. I agree that comfort will be better with a taller sidewall, but then if that's the priority, you need to stick to the stock rims - That's why I didn't change to bigger wheels.


Drive a car back to back with shorter sidewalls and you'll be able to notice a significant increase in tyre roar. Read page 72 of this http://ec.europa.eu/enterprise/sectors/automotive/files/projects/report_tyre_road_noise2_en.pdf

I personally changed from 215/45/17 tyres (what the wheels came with on the ST-R) to 215/50/17 tyres and noticed a huge reduction in road noise.




On a sweeping, perfectly smooth bend - Yes.
However, there's more to consider. Wider tyres are more prone to aquaplaning. Not good for grip and/or braking distances in the wet. I think I'm also right in saying that wider tyres can tramline more over bumps?

But again - we're not talking huge differences here.


I think we'll both agree there are small differences, but wider tyres do overall increase the level of grip. I'm not advocating moving to something like 225/35/19 with a very minimal sidewall which will inherently feel fidgety over bumps but actually going to a slightly taller sidewall which will improve ride, grip and feeling over bumps, all the while providing more grip due to increased width. The differences will of course be small.



Really? Hmmm. I'll check on that.


F1 Asymm, Hankook R-S3, both of which are high performing tyres. Actually on 1010tires and tirerack there are nearly double the amount of 225/45/17 options over 215/45/17! 78 vs 159 and 65 vs 102 respectively.



We're talking about a prefacelift car here Brad....


And why do you think they changed the high performing Type S to wider tyres over the Type V and prefacelifts? I've run 225/50/16 on facelift wheels on a prefacelift and they work well. I can't see why anyone would ever want to 'upgrade' to something that is narrower than what came on a stock model!



Hmmm. Just a second. I need to go and sue Mitsubishi for selling the VR-4 and the V6 Sport... And in fact every other sodding model of 8G, 7G, 6G et.al. with the wrong size tyres! I could have died horribly every journey! Christ, it's almost a relief that I've not finished the Yellow Peril... I hate to think what'd happen if I took that out with it's 165x13 steels of retro on! I'd probably have exploded in a ball of fire before I'd left the driveway(!). I know you're referring to just 225s on a 7.5 rim, but you see what I'm getting at. There's nothing wrong with 215/45R17s on a VR4 provided they've got the appropriate speed and load ratings.


I bet it'd go around corners faster with 195/50/15 tyres or 205/45/16 :D

Some cars are supplied with perfectly fine sized tyres. Let me think of an example of a car that has a similar weight and size to a VR-4. First one that pops into my head... EVO 7-9 with 235/45/17 tyres. Then the EVO X, 245/40/18. How about Subaru's? 225/45/17 was a common size on the bug eye and later facelifts of the STI.

In fact, you find me a car that is around the same weight as a VR-4 (I'll accept up to 50kg lighter) with equal power and torque (or more or less within 10kw and 20nm) with narrower tyres than 215mm made in the last 15 years.

[VR4Kaos]

Omg what have I started hear and I'm so confussed my head hurts hahaha
so what is the ideal size and offset then ?

[Wodjno]

Omg what have I started hear and I'm so confussed my head hurts hahaha
so what is the ideal size and offset then ?

35-42mm i think /help

But that depends on the tyre height, width, depth, load rating, wheel size, wheel width etc etc :bigcry: /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot /megawoot etc

[Kieran]

Sorry guys... :sigh: /Hijack


Most cars have optimistic speedo's. Witness: http://www.google.co.nz/search?q=optimistic+stock+speedo&rls=com.microsoft:en-nz&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1&redir_esc=&ei=cvzLS_b_M5Dc7APi3rj9Ag

I can't beleive Kieran that you've never known that?


Umm - Yes I did. I used to own a Fiat Cinquecento, don't forget! ;) However your statement suggested that having the stock tyre size would cause an inaccurate speedo reading - rather than it being the error of margin on the speedo clock itself. I must have misinterpreted what you meant.


I'll accept it is insignificant, but a 225/45/17 near the end of it's life is going to be closer to the stock 205/55/16 than what a 215/45/17 will be!

Excellent - We agree that whilst factually correct, this point isn't worth further debate as the difference is insignificant in daily driving.:scholar:



....For example in the 225/45/17 size on tirerack.com there was 1 on the first two pages that wasn't either 91 or 94. I will accept that yes, you can get a 215/45/17 in 91 which is stock, but don't you want better than stock?

To clarify... Your logic is that I should put a wider tyre on my car in order to get stiffer sidewalls, correct?


I know you're smart enough to understand the massive cornering forces at work, witness: http://www.autozine.org/technical_school/handling/tech_handling_3.htm

Even if you halved those weight transfer figures - unlikely though as a Boxster will have a lower CoG than a Legnum! You can imagine that a VR-4 with a static weight of around 450 to 500kg on each front wheel could easily be in the region of 600 to 700kg of weight on the outer front tyre in a corner. This amount of transfer is going to be worse on a stock car, just the type that is going to have undersized wheels that have a low load rating. Ironically the people with wide tyres will probably also have at the least stiffer springs than stock, and possibly coil overs and uprated anti roll bars to reduce the amount of weight transfer!

Actually - No I'm not smart enough; maths and physics aren't my strongest areas. But irrespective of that, I don't understand the relevance of what you've written there. Mitsubishi specified 205/55R16 89w from the factory on the pre-facelifts to deal with the cornering forces at work. Had this been under-specified, I'm sure the CVR4 Castle Combe casualty list would be much higher. I don't dispute the facts & figures you're quoting Brad... but I think you've missed the point with regards to day to day driving; Provided the tyre rating is within the specifications of the vehicle, there's no issue.


Drive a car back to back with shorter sidewalls and you'll be able to notice a significant increase in tyre roar. Read page 72 of this http://ec.europa.eu/enterprise/sectors/automotive/files/projects/report_tyre_road_noise2_en.pdf.........I personally changed from 215/45/17 tyres (what the wheels came with on the ST-R) to 215/50/17 tyres and noticed a huge reduction in road noise.

Interesting document - Thank you. Having read page 72, I see that it says that 'Plus sizing' is inconsistent with lower noise levels. It is a shame that it doesn't state whether it's the sidewall or the wider tread that is the main cause.I presume when you swapped that the tyres were from the same manufacturer and the same model of tyre?



I think we'll both agree there are small differences, but wider tyres do overall increase the level of grip. I'm not advocating moving to something like 225/35/19 with a very minimal sidewall which will inherently feel fidgety over bumps but actually going to a slightly taller sidewall which will improve ride, grip and feeling over bumps, all the while providing more grip due to increased width. The differences will of course be small.

Excellent - We agree that whilst factually correct, this point isn't worth further debate as the difference is insignificant in daily driving.:scholar:


And why do you think they changed the high performing Type S to wider tyres over the Type V and prefacelifts? I've run 225/50/16 on facelift wheels on a prefacelift and they work well. I can't see why anyone would ever want to 'upgrade' to something that is narrower than what came on a stock model!

No-one has suggested to fit a narrower tyre than stock. The prefacelift has 205/55/16 tyres as standard, and as I recall this discussion started with your statement that a 215/45/17 tyre was 'wrong'.


Some cars are supplied with perfectly fine sized tyres.

The Galant and Legnum VR-4 being a good example. The stock size works well. I agree that upgrading to 17s can bring grip/feel benefits.. But it's not mandatory that people instantly upgrade to 225/45/17 tyres.

I think overall this discussion highlights that we have somewhat different views regarding tyre choice, Brad.

My overall point though, which is still valid, is that the stock size works well enough. If you want to upgrade - go ahead; there are some benefits from doing so. But we shouldn't be saying that a particular size is wrong, at least not without good reason - And I don't see any good reasons above to start advising members not to go for 215/45R17 tyres. There's nothing wrong with 215/45R17s on a VR4 provided they've got the appropriate speed and load ratings. Sure - there may be better choices... But that's a subjective assessment and what's 'better' for one person will be worse for another. Let us not forget that. :)

Anyway... Sorry Karl, we'll stop hijacking your thread now. Where were we anyway? What's the situation now - Still got rubbing issues?

[VR4Kaos]

/pale yeah i sure do Kieran mate :( wow so blown away by this thread talk about all the info that you will ever require is not in it btw there no need to apoliagise.
defo changing them wheels not just because of looks anymore but because they be the incorrect size !!!!! :lost:
"o eye" and this thread also just show's how deep out of my depth i am with you guy's for sure/pale

[Kitty's VR4]

Did you lose your gumboots Brad? I didn't think you were part of the size/offset nazi squad !!!

[bradc]

Kat - no I'm not an offset Nazi, I just get annoyed when people run completely incorrect sized wheels and tyres!

Kieran - I'm going to continue to argue with you because I still beleive you're wrong! :)

In response to the wider tyre = stiffer sidewall comment, that may not always be true in every case. What I'm arguing here is that the shorter sidewalls on a 215/45/17 tyres that are rated at a lower load level is not a good idea.

Regarding weight transfer, if a tyre is rated at 91 then it is designed for 615kg which a VR-4 would easily go substantially over in normal cornering. 670kg would be quite a bit harder to exceed and would only happen in hard cornering when you've got the AYC bars flashing like mad. I wouldn't have much faith in an 89 rated tyre at only 580kg when the car is going to be close to that when static!

Upgrading from 205/55/16 tyres to just about anything on a 17" wheel will give large improvements in feel and grip. It is one of the most popular modifications on the forums, right up there or even surpassing exhaust and a boost controller. There is a good reason for this, and I do remember you saying that when you were in Ariadne again with larger wheels and tyres (I think EVO 7 wheels with 225/45 or 235/45 tyres) you noticed that it felt a lot better.

[martin_y]

Lets not forget that anything in engineering is always a compromise, so any modification you do is a compromise somewhere, so its really difficult to say anything on a car is "right" or "wrong"

[Turbo_Steve]

You reckon 615kg is easy to achieve in cornering but 675kg is difficult?

[bradc]

675kg will be harder to acheive that 615kg in normal driving

[martin_y]

Its been a very interesting thread so far, especially as Ive just bought Evo 7 wheels, that came with 2 of 215/45/17 in good condition. Then I bought 2 new tyres (Conti sport contact 3) and have them on the car now.

I wasnt sure if a 225 would rub or not.

Now I have a predicament, because I have 2 tyres that will need replacing way before the new 2.

Could I put 225s on the back and 215s on the front? What will the transfer case think of that?

[elnevio]

Wouldn't like to do it Martin, especially as the 215s will be more worn compared to the 225s. As the 225s will give you a slightly larger rolling radius as it is, this will be exaggerated by the different levels of wear.

I'm surprised they already had 215s on E7 wheels, I thought that would be a bit of a stretch? I think E7 wheels are 8" wide as standard?

[Turbo_Steve]

675kg will be harder to acheive that 615kg in normal driving

I wouldn't have thought so - I've just been rerunning the maths, and we're talking the difference between 1 and 3 AYC bars.

In fact, by my reckoning using your weights above, the front tyres exceed 615Kgs under heavy braking.

[Turbo_Steve]

The E7 may have been under tyred to make it feel more directional and responsive.

[Kitty's VR4]

Kat - no I'm not an offset Nazi, I just get annoyed when people run completely incorrect sized wheels and tyres!

LOL, I can live with the fact that I have annoyed you then. 17x7 ET45 with 235/45/17, always been partial to love handles.

[Turbo_Steve]

/splurts coffee all over monitor

[elnevio]

always been partial to love handles.
/checks Mrs B isn't looking

/Wyhy :sweethear






:uhoh:


:dalek:

[Kieran]

....always been partial to love handles.

/Nips out for 30 HappyMcBurgerHutStarbucksExpresses...:d

[bradc]

Kat, your tyres are fine but you really should be running those on 17x8 or 8.5: wheels

[miller]

Kat, your tyres are fine

No wonder your single if thats the height of your romance :coat

[Turbo_Steve]

/Nips out for 30 HappyMcBurgerHutStarbucksExpresses... How do you know what I had for lunch?




No wonder your single I don't think that's got anything to do with his tyre fetish.....maybe his unshakeable inability to be proven wrong, though. That doesn't go down with the ladies well at ALL.

[Kitty's VR4]

Kat, your tyres are fine but you really should be running those on 17x8 or 8.5: wheels

:-policema Where I live, the law says four things about aftermarket wheels; :-policema
1,) you may not increase the diameter of the wheel by more than 1" from the manfacturers original maximum wheel specification. /bat
2,) you may not increase the width of the wheel by more than 1" from the manfacturers original maximum wheel specification. /bat
3,) you may not change the original wheel offset by more than + or - 1/2" or change the original geometry so that it effects vehicle tracking by more than 1" overall. /bat
4,) Wheel spacers cannot be used unless they were originally fitted by the vehicle manufacturer. /bat

:censored: So the maximum size wheel I can use accordingly is 17x7.5, and unfortunately the range of 7.5" wheels is crap IMO. :censored:

/pan So now your arguement will be that the tyres fitted are larger than recommended maximum for 7" wheels - Guilty Guilty Guilty, but I have an excuse mien Führer, I'm a mere female and my parking skills are crap, and all the gutter in town are 9" high of brick or sandstone construction, very unforgiving for a mere females parking abilities. Now IMO this combination doesn't adversely effect the handling of the car given that I'm limited to 50kph in town and all other driving is on 110kph multilane motorways, so no twisty stuff. AND I'M PARTIAL TO LOVE HANDLES

/Steeringw I fit my track wheels for any club events/cruises and for my monthly track days.... oh dear there 17x7 too, and oh no 215/45/17 Toyo 888's semi slicks. These equate to being 3 seconds per lap quicker than the 235/45/17 combo. /Steeringw

/hammer So lets cut to the chase, mien Führer, you have your idiology and I have mine. You Like Goats & I Like Love Handles !!!!! /hammer

uploaded/57846/1271900078.jpg
Parking skills are Crap & I have a thing for Love Handles = WIN, WIN for me

[Zitchu]

Wow those are some **** wheel rules.

[bradc]

Should run EVO 7 wheels and say they are stock

[Turbo_Steve]

So drag cars over-tyre to put the power down better.
Tarmac spec rally cars overtyre to grip better.
Gravel spec cars tend to use narrower wheels anyway to improve directionality.
Snow spec cars tend to use thin wheels undertyred as much as possible to maximise traction and directionality.

So there ARE reasons to run unusual wheel / tyre combinations.

What is the concern with running an undertyre or overtyre, exactly?

[John TheAntique]

Karl,
Has your life always been complicated????

Regards and congratulations,

John

[bradc]

Tarmac rally cars don't have tyres mounted on wheels narrower than the recommended though

[Turbo_Steve]

That's because there isn't a manufacturers reccomended guideline on what tyre a tarmac spec rally car should use (well, unless it's group N, and then you'll find that the reccomended spec listed in the racing manuals...and frequently the tyre is slightly smaller than the rim, don'tcherknow :D )