More grip needed

[Wabbitkilla]

I don't know what sizes other people are using - Exileye_xc might step in here with some useful info as he's running 17" all around.

Sounds good though, just not sure if you need the 45 profile on the front, 40 might be better.

[roger]

Silverstone Performance put 205/40 and 215/40 on their 7 1/2" rims.

Presumably figuring out what your rim size is, and are they all the same or bigger at back, will make a difference to the tyre choice.

[firepower]

this is my understanding of the reason for tyre stagger

the mr2 is mid engined rear wheel drive so has a weight bias towards the rear of the vehicle , if you corner at speed this weight bias will tend to swing the rear of the car round from a pivot point just behind the seats    ( oversteer ) to counter this wider rear tyres and narrower front are fitted to build in some  ( understeer ) to keep a safe balance between oversteer
and understeer.

all mid and rear engined cars seem to be set up this way as it makes them safer to drive .

with front engined front wheel drive vehicles with the weight of the engine over the front wheels the vehicle will tend to understeer as a norm which is considered safer than oversteer so a tyre stagger is not required

[Jaik]

That and being rear-wheel drive increases the slip angle of the rear tyres when cornering with any throttle on, which natural induces oversteer. The weight is also closer towards the centre of the car when mid-engined which makes them easier to change direction (it's what makes them feel like they turn so effortlessly) so if the back-end does go, you need to be quick to catch it!

[Anonymous]

Let's knock this nonsense on the head straight away that there is inherently anything wrong with the same size tyres all round.  If anything fitting relatively fatter tyres on the rear may make a car more snappy - I've always found a car that understeers more to demand the pilot be more awake for when the rear finally does let go.

Furthermore, the attitude of looking to improve road safety by giving your car more grip shows you have learnt nothing from your crash.  Try to be more introspective first rather than trying to blame your car - you won't learn anything if your answer is just to spend more money - you'll just have a bigger and potentially less fortunate outcome next time around.  I'm more than happy to confess to three crashes in recent times - two in an MR2 no less - but in each case driver error played at least some part and its identifying why and where you went wrong that will make you a better driver instead of questioning your equipment.  Things are never black and white - the driver, the car, the conditions, and what you ate for breakfast will all play a part in your chance at stacking it one day, but you can do a whole lot more than just plonking poorly judged fat rear tyres on your car.

Unfortunatley recommending anybody actually gets some track time or tuition on here is enough to risk a censored post or a ban (despite it being in the best interests of the members and their insurance premiums), which is a shame as when I read something like this...

but never taken it into a spin before. As exciting as it was I have now become really nervous when driving it and would love to feel 'safe' again.

...it sounds like getting to stretch your car to its limit and beyond would not only restore and exceed your original confidence but make you a vastly better driver too.

[aaronjb]

Unfortunatley recommending anybody actually gets some track time or tuition on here is enough to risk a censored post or a ban .

I'm sorry, but where did you manage to get that idea into your skull?  Many people have recommended exactly that in the past so please, don't throw misleading statements like that around.

[markiii]

I'm not going to get into this particular argument again and Jules does have some valid arguments in that last post however for those willing to search they will see

on the left those that think same size tyres all round are bad, pretty much everyone

and on teh right those that see it as no problem at all, it's Jules and oh yes let me see several people who thought it was and then stacked there cars and left.


draw your own conclusions

[Anonymous]

Let's knock this nonsense on the head straight away that there is inherently anything wrong with the same size tyres all round.

In a FWD/4x4 setup I'd agree, but with regard to the MR2 you're wrong Jules, and the fact that you've recently stuffed your car into the armco on track would seem to back up that fact if indeed you were running same size tyres all round.


Johnny got a polite message informing him that he was technically making a commercial post, and he then threw his toys out of the pram in very quick succession. No ban, no censor, just an unwillingness to co-operate with the good people who run this site. FWIW I've always recommended BaT as a TDO and will continue to do so, and again as a supplier of tyres and noise-testing gear. However, I don't get any benefit out of that, whereas Johnny does. Big difference, methinks.

[loadswine]

I seem to remember that Tem actually tested this under controlled conditions ( and he can control a car properly). He concluded, and I think most sensible folk agree here:-

Basically same size all round = snap oversteer and therefore more likely to have an incident the average person won't be able to control i.e. accident

Stagger= more progressive breakaway and more likely to give you a chance of avoiding an incident.

We've seen the results ,so often ,of people thinking they know better.

[Wabbitkilla]

Let's knock this nonsense on the head straight away that there is inherently anything wrong with the same size tyres all round.  

The vast weight of evidence to the contrary on here and Spyderchat.

Furthermore, the attitude of looking to improve road safety by giving your car more grip shows you have learnt nothing from your crash.  Try to be more introspective first rather than trying to blame your car

Again on the contrary, he admits he may have been a bit over-zealous in his druiving which caused the spid, all he was asking for was recommendations for improving grip.

- you won't learn anything if your answer is just to spend more money - you'll just have a bigger and potentially less fortunate outcome next time around.

We bow down to your superior knowledge, but you are coming across as a bit high handed there, where the rest of people offered constructive advice from years of experience.

I'm more than happy to confess to three crashes in recent times - two in an MR2 no less - but in each case driver error played at least some part and its identifying why and where you went wrong that will make you a better driver instead of questioning your equipment.  Things are never black and white - the driver, the car, the conditions, and what you ate for breakfast will all play a part in your chance at stacking it one day, but you can do a whole lot more than just plonking poorly judged fat rear tyres on your car.

What tyres were you using each time you stacked the car? We all make mistakes and some people get away with them, if your driver error was at least partly to claim, what else was "mainly" to blame? Tyre selection per chance?

Unfortunatley recommending anybody actually gets some track time or tuition on here is enough to risk a censored post or a ban (despite it being in the best interests of the members and their insurance premiums), which is a shame as when I read something like this...

Again on the contrary - if you want track experience to learn better driving, then pretty much everyone is for it. However if someone tries to sell tyres on the back of that statement then they're breaking the rules of the forum.

...it sounds like getting to stretch your car to its limit and beyond would not only restore and exceed your original confidence but make you a vastly better driver too.

As long as they don't trash it in the armco! Get an instructor in with them to push the car to its limits and their confidence will grow. Just chucking meat on the race track only does good things for buzzards.

Really i think we've got well away from the crux of the subject. Advice has been sought about grip, tyres, etc and it has been given. People make mistakes and it is the aim of this posting to try and encourage towards safer better driving.

[Jaik]

Let's knock this nonsense on the head straight away that there is inherently anything wrong with the same size tyres all round.

The MR2 was developed to run wider rear tyres. The inherent problem with fitting the same size tyres all round is that you are ruining the balance of the handling, often to an unsafe (for most drivers) level.

Like I said before, having the same size tyres all round on the MR2 is like fitting narrower rear tyres to a car that has equal sizes from the factory. If you don't understand that then I would say you're not in a position to give the advice you're giving. If on the other hand you do understand, I'd like to know your reasoning for thinking it's not a problem?

[Anonymous]

You know nothing about the circumstances of my accident, so that's an impressive conclusion and entirely indicative of the sort of attitude I am on about - i.e. looking at the car and not any other factors.  I'm surprised you didn't take the opportunity to highlight the dangers of same size tyres all round when I crashed my car whist parking.  FWIW I will be running the exact same tyre configuration as before when normal chassis shape resumes.  Why?  Because my tyre configuration played no part, and in fact I believe prevented several other mishaps in unpredictable conditions.  Unless you are willing to backup your idea with personal experience amounting to something more than a couple of miles on a Tesco's car park, or what happened to Bill's mothers MR2 (where again, I presume you wasn't in the car) then I don't know why you persist with an idea which defies conventional logic.

However if someone tries to sell tyres on the back of that statement then they're breaking the rules of the forum.

I'm pretty sure that was not the case and you are overlooking the fact that in the aforementioned incident the tyres one of the groups members was about to buy were more expensive, so how could allowing somebody to go on and buy them be considered in his best interests?  FWIW we don't make any markup worth getting excited about on tyres, we only offer them as an added service to the track side of things.

I don't think there is a problem with people recommending services or whatever on here, though it does seem that if you are affiliated with any such company it automatically becomes a commercial post.  I think anybody that posts under their own name regardless of if they are affiliated with a company or not are giving an honest advice or opinion - there is plenty of opportunity by less sincere individuals to create bogus for personal gain, though I've never been convinced that online groups ever hold any commercial weight to be exploited legitamitely or not.

We bow down to your superior knowledge, but you are coming across as a bit high handed there, where the rest of people offered constructive advice from years of experience.

My post was intendde as nothing but supportive and constructive - you can quote individual lines if you like but given all of the sheep wittering on about tyres and overlooking the obvious I considered a short sharp attack on the idea that his car was to blame was very much appropriate in this instance.  Given the fuss this has stirred up perhaps this was a good thing as I certainly don't think the direction the topic was taking was of much benefit to the original topics poster.

Let's get back onto topic - does the majority of the group honestly think that all of Rio's problems are purely tyre related?  It's a fairly sorry state of affairs if this is the case and also somewhat worrying.

[Anonymous]

So what tyres were you running then, Jules? Enlighten us if you would be so kind. If you say that you're running same size all round, then I guarantee that it was most certainly contributable to your accident, whatever you and your super-driving skills may think.


I've driven on same size tyres for a decent trip after buy a set of wheels that came with them on. It was dangerous, skittish and unpredictable, and they came off as soon as I got home. That's my own personal experience, and one I stand by. Having the same size tyres all round defines conventional logic, not the other way round.



Were all of Rio's trouble tyre related? No. I'd say they were about 95% the reason though, as unless he was stupid with the loud pedal (and it's hard to be with only 140bhp), then it was the total lack of rear traction in relation to the front that caused the spin.

[loadswine]

I would be very careful about considering our members as sheep Fanjules.
The majority of our membership can , and do think for themselves thank you!
I am sorry the OP had an accident. I would like to see them in a safer position in the future, so a staggered setup will go some way towards that aim.
I think another message is to take things sensibly when the conditions are slippery as well.

[Anonymous]

I crashed my car whist parking

More effective than staggered tyres in this situation, I feel.


I'll give you that one, I think.

 s;) s;)   s;) s;)   s;) s;)

[evileye_wrx]

Baaaa!

[Anonymous]

So what tyres were you running then, Jules? Enlighten us if you would be so kind. If you say that you're running same size all round, then I guarantee that it was most certainly contributable to your accident, whatever you and your super-driving skills may think.

I was running same size tyres all round.  Again, I don't see how you automatically put two and two together to make five.  My driving skills are very much average (or worse), I don't see how I claim to be anything more if I say "it wasn't my tyres it was me"!

You are disregarding the actual tyre model, compound, PSI and such like.  "Don't fit the same size tyres all round" is a hugely sweeping statement.  Perhaps same size Bridgestones all round is a nightmare.  Perhaps same size Hankook's is totally fail safe.  But in my personal experience I have driven thousands of miles and consumed 12 tyres with no problems attribuitable to the configuration, in a variety of conditions on road and track.  You should not interpret this as God-like driving skills (anybody who knows me personally is happily aware of how I shy away from out Batcats and Elise hire cars) more an indication of real-world proved experience of a safe configuration rather than misguided theory.

I would also recommend the setup for a halfwitted driver - the car has been driven on road and several trackdays by a driver that had a reputation for "a bit of a crasher", a girl that had 3 wrote off cars in 18 months or thereabouts.  In the safe hands of instructors, and sometimes not, she had no major dramas and the times I do recall the car doing things unexpected she was able to identify what was happening and gather it up.  In the original tyre configuration I would have been a lot less comfortable with this driver exploring the vehicles dynamics.  She was able to rebuild her confidence in this car and if my MR2 wasn't such a shitheap I think it would serve as a great tuition tool as an introduction to mid-engined driving.

I've driven on same size tyres for a decent trip after buy a set of wheels that came with them on. It was dangerous, skittish and unpredictable, and they came off as soon as I got home.

Had my experience with the configuration been the same as yours - on the road - I would have been inclined to agree with you.  But I had the good fortune to have a far more skilled driver than myself do the evaluating for me on track.  I didn't really want the tyres on my car - I knew the MR2 had a bit of a reputation and that adding wider tyres at the front and narrower ones at the rear would make it even worse - but my existing ones were shot so we had to stick something on.  I wanted to be told it was safe for a halfwit to nurse around (meaning myself), but the "test driver" in question concluded if anything that it was safer than before because it was more talkative.  And that's exactly how it feels - that nervousness you talk of is how it feels initially - seems like you're one millisecond from an accident at any one moment but it actually translates into a far greater definition of communication when you are actually in a state of slip.

And you can be hopelessly cumbersome with your inputs and it's hugely forgiving.  As a passenger when they were first fitted, I specifically asked the driver to try driving like a half wit (going into corners too hot, making sharp stabbing steering inputs and dabs on the brakes), to emulate my own incompetness at the wheel to see how dangerous it actually was beyond the limit.  But it was like a pussycat, and I was totally surprised.  Try to have a more open mind - though I can see tha if these circumstances were reversed I'm sure it would be me pouring scorn on this muppet with his silly tyre configuration!  s;) s;)

[Wabbitkilla]

[firepower]

just one point with regard to tyre stagger if it is not necessary why is it that all manufacturers of rear and mid engined cars do stagger the sizes .
Porsche , Farrari , Lotus , Lambo , Noble , pagani , F1 , oh and toyota   s:?: :?: s:?:  

i would presume that these companies have spent millions on research and testing

[Anonymous]

Right, I'll concede that an expert driver could keep a same-size MR2 on the boil on track, but they'd have to know the track very well and be a very good driver. For the average person who buys an MR2, from the total MR newbie through to the more experienced driver (and I'd include myself, all the old hands on here and you in that catagory), it's simply a disaster waiting to happen regardless of tyre make.

Look at it this way: If you've got all Bridgestones all around you've still got less grip at the back. If you've got all Toyos all around you've still got less grip at the back. If you've got 048s all around you've still got less grip at the back. Tyre choice matter not a jot here: The semi-slicks will grip more than the Bridgestones, but you'll still not have the balance and that's the main issue.

I can't think of a single modern MR car that has the same size tyres front and rear. MGTF to Exige to Gallardo, the MR platform works so well as you put more rubber at the driving end so that when weight transfer occurs during a corner, it remains tractable (within reason, of course: Heavy handedness is a killer in these cars).


Your example of your friend who started learning again in your car does actually work, as because the arse end is a billionty times more likely to come around you soon have to adapt your driving style to a more conservative one, which will always end up being slower and therefore more stable.



If you really wanted to ever prove a point on it, then I've got a set of 17" wheels in my garage shod with T1S rubber in 205F/215R sizes, which is by far from a perfect setup as the stagger isn't quite enough, and they're also heavy as hell. It's not impossible for me to bring them to a track of your choosing (since you get free tracktime  s;) s;) ) and you to drive a few laps with your setup, and a few on my tyres. I can guarantee that you'll be quicker on my tyres after a few laps getting used to the extra grip available. Dead serious offer, no small print, could do it under test conditions if you liked (if you could wangle use of the track at lunch when it's empty so you have no other traffic, and we'd record everything on videotape so no timing would be done at the track itself, neatly getting round the insurance issues  s;) s;) ).

[Anonymous]

just one point with regard to tyre stagger if it is not necessary why is it that all manufacturers of rear and mid engined cars do stagger the sizes .
Porsche , Farrari , Lotus , Lambo , Noble , pagani , F1 , oh and toyota   s:?: :?: s:?:  

i would presume that these companies have spent millions on research and testing

I think this statement hits the nail on the head, no matter what you say you cannot argue against this fact.

Rob

PS There's an "e" in Ferrari

[Anonymous]

Firepower - nobody is saying it's not necessary, nor is anybody saying "this is the way Toyota should have done it".  There does seem to be quite a crowd that believes it translates to instant death rather than there perhaps being a variable transition.

There are many ways to balance a car between handling traits, and it's not always through tyres.  The S2 Elise for instance, has quite dramatically narrower front tyres relative to the S1, but does not understeer like a whore.  The VX220 has even narrower front tyres (in fact the stark difference between front/rear tyres is no more stark than on an upturned VX220), though as I understand it this was the most obvious means to make it handle more safely for the sort of customers that would buy a VX220.  The MR2 has comparativley wide front tyres (I believe this is a significant reason why it has excellent braking performance).

As an aside, is "tyre stagger" the correct term?  I think it's perhaps slightly misleading - the only time I have came across this before is with stagger in oval racing, where the outer tyres are slightly larger in the circumference than the inner tyres, thus aiding grip on a circuit where you only ever turn left.   s:P s:P

[Anonymous]

The S2 Elise for instance, has quite dramatically narrower front tyres relative to the S1, but does not understeer like a whore.

s:shock: :shock: s:shock:  

The 111S I drove on track did, much more so than the MR2. Not driven a 111R in ages so can't really compare that, as the last one I drove was pre-VXR ownership.

The VX220 is indeed setup to understeer quite a lot from the factory, which again proves the point that you want as much grip at the back as possible for  the more inexperienced driver.



And yes, I do believe that stagger is the correct term to use as that's what I've seen used everywhere else in the world ever. Oval racing excluded, of course.  s;) s;)

[Jaik]

I understand what you're saying with the different car models, but they all had their suspension setups and tyre choices tuned to work together, just like the MR2.

Edit: And yes, I believe even Lotus said the S2 was setup to have more understeer than the S1 so the average driver would be able to exploit the handling in a little more safety.

[markiii]

I rather disagree that the s2 elise doesn't understeer on it's skinny fronts

it was designed that way (I'll take the word of the Lotus factory test driver who told me that) for the market that was envisaged to be buying it.

And since Lotus sell wheels with wider fronts as an option I rather think they know it

having done a handling course in an S2 the instructors had to put deliberatly narrow widths on the rear in order to get enough oversteer they could teach us how to catch it.

strange both Exige and VXR both aimed at the more competent/enthusiastic/track focused driver than the mainstream models have a reduced stagger don't you think

no one is arguing that changing the stagger may improve the handling, nor tune it more to individual tastes. Some people prefer oversteer.

However your average MR2 is owned by people who are new to the world of mid engined cars, because they are so cheap.

for those kind of drivers with limited experience understeer is always going to be safer, thats why they are engineered that way.

yur cavalier approach to assuring all who will listen to not worry about tyre widths is irresponsible at best

I'm certainly glad the stagger was there when I bought mine, or I'd have been in a ditch the first week