This ^ Although it's probably not going to hurt to go up or down a speed rating or two (I had to before because my OEM speed rating wasn't available for the tyre I wanted in OEM size), but there's a remote chance the insurance might try and use it as an excuse to avoid paying out. Changing thetyre width and profile is far more significant than a speed rating. I wouldn't scrimp on tyres though, they're the only thing that hold you to the road and in an emergency they can be the difference between a near miss and a collision; I've bought cars with Chinese plastic tyres and fitting proper rubber makes a huge difference, especially in the wet.
550 Maranello. It was an industry test day where a bunch of manufacturers turn up with some cars and let a bunch of people loose in them. A friend and I went out in a pair of Maserati 3200s and went round at 150-155mph, taking it in turns to slipstream each other. IIRC I did a few laps in a 456 (lovely thing) and did something like 160 in that and when I had a go in the 550 next I thought I'd see how fast it would go. After three or four laps getting it up to speed I did a lap as fast as I felt comfortable. All great fun but I had missed the driver's briefing at the start of the day and had no idea the limit was 100. Apparently some people were pulled up over it but I heard nothing of it. It honestly wasn't that difficult, the car was amazing, but in hindsight it was completely idiotic!
"A man of little significance"
Porsche only spec'ed N Rated Tyres, and leave the choice to the owner, but they need to be N Rated.
I have tried Yokos and Dunlops, and am now using P Zero Rosso's which wins hands down in terms of performance.
People need to remember that the tyres are the only thing that connects the car to the ground hence cheap or bad options can be very expensive in the long run.
Ref the tyres used on a Prius. These are super hard designed for reduce rolling resistance and better efficiency, but noisy. My wife uses Michelins. I cannot believe toyota also specify them on a sport car (unless it's very slow). The top end on a Prius is about 103mph
Whoever does not know how to hit the nail on the head should be asked not to hit it at all.
Friedrich Nietzsche
Hands up, my mistake. Seems that the Isle of Man is a Dependency and not classified as part of the U.K. :(
The PORSCHE N Spec requirement is not a speed rating like the other letters mentioned here. It is more like the BMW star symbol, an indication that the tyre is approved for use by them, nothing more. Porsche’s have top speeds ranging from around 140 to 210mph. The tyres for each model are different with different speed ratings but all N rated as suitable for fitment, it’s nothing to do with speed.
Last edited by Padders; 8th November 2018 at 20:48.
The ´sports car paradox´ again.
Speed does not make a sports car and bulk or weight únmake it.
The reason why Toyota put the hard ecos under the 86 is that the car will behave exactly as with grippier tyres, only at lower speeds, thus easier to control, thus safer fun drifting the car. Remember that thís was the object of the project; a modern tech AE86.
Have a look at
https://www.youtube.com/watch?v=HPh90yNX-mY
and you should get it.
I was due to drive the Indy they had there too and while I was waiting went out with the person one or two before me on the list and the car didn't sound too happy, they'd not thought about a lack of baffles in the sump and after going round and round the banked circuit for however long had started starving the engine of oil. At least I had a ride in it! The 3200 was very nice indeed and much more subtle than the current screamy-shouty LOOK AT ME Maseratis. I suppose a bit like the 550 was (along with the 575) the last subtle Ferrari V12 two-seat GT.
"A man of little significance"
Indeed, however my insurance company expect them to be used, hence the manufacturers recommends/approval are important irrespective of the speed rating.
Given the speed limit on UK is 70mph you could in theory fit 70mph Rated tyres (remoulds?) to your Bugatti, but I very much doubt your insurance company would insure it.
Whoever does not know how to hit the nail on the head should be asked not to hit it at all.
Friedrich Nietzsche
I've always thought speed ratings of tyres and the matching to vehicles have been off for some time.
The majority of Rover Sports come out of the factory with tyres rated as Y which off the top of my head is c170 mph. Firstly afaik apart from perhaps some heavily modifies vehicles those kind of speeds are t reached. I know it's good to have a little bit left over but even so.
Load rating imo in most applications is far more important than speed rating.
One thing that needs to be remembered about speed ratings is that if you have a tyre which is under/over inflated, has damage, badly worn or puncture repaired then the speed rating goes out of the window.
In real terms that probably covers a good majority of cars on the road.
I understand. But no manufacturer would recommend 100 mph Rated tyres (for example) for a 150mph car and no insurance company would sign off on it.
Plus the Gt86 seems to have 215/45 tyres where as a Prius is fitted with 195/65 so I am not sure they can be same.
But like foxy - past caring.
Whoever does not know how to hit the nail on the head should be asked not to hit it at all.
Friedrich Nietzsche
Who’d want to drive on tyres designed to safely do 71mph, even if you never went above 70mph? Not me.
It’s entirely sensible to design and fit a tyre that’s capable of exceeding the design limits of the vehicle it’s fitted too, rather than just the speed limits where it will be used.
It should mean tyre failures are pretty rare, which they seem to be.
I was told years ago by an engineer its more to do with cornering forces and heat displacement rarther than top speed
I suppose you could argue tyre speed ratings are bit like water resistance ratings on watches; 100m water resistance in case you drop it in the sink or it gets rained on! But nice to know it will be okay and we all know 100m static is not the same as actually swimming at 100m. You might only go 70 mph (+VAT) but having a tyre rated in excess gives safety margin and could improve overall grip and handling.
Fantastic to have a go in an Indy. When I bought my Spyder they had an Indy that they had restored for a customer; I made two or three trips before collecting my car, each time they found an excuse to fire the Indy up.
I know what you mean about the modern ones, sound fantastic but I think the 4200/Spyder series were the last to retain the DNA of the ‘60s and ‘70s models. Despite having bits of 430 and 360 in them.
Already amended.
Insurance isn't invalid at all, it's never happened (Although its often rehashed as the excuse ill trained tyre fitters come up with)
A H rated tyres is ok up to 130mph, even if you have a car which is capable of significantly more, the insurance can only become invalid if it was a contributing factor in an accident. If that accident happened in the UK, your insurance will be void due to recless driving any way. (And if you were going over 130mph in the crash, your life insurance is probably more of interest than vehicle insurance.)
Who says M&S are excempt and summer tyres arent by the way?