TYRE HELP

[Hilux]

The ABS works with a magnetic sensor reading a castellated ring around the hub. How can it have the faintest idea what tyres you have on?

It can cos if its calibrated for a particular rolling diameter/circumference its accurate enough to know that something is out of kilter and that your tyre is burst or deflating and so warns you on the dash via the ecu/ABS (hence modern low tyre pressure warning systems are clever and cheap) []

Its true, if you dont believe me look it up []

 

[sawood12]

ORIGINAL: mik_ok
I'd be happy with that personally ~ 205 on the front with 255 rear seems like waaaay too big a difference for such a well balanced car.

205's up front and 255's on the rear are the standard sizes on Boxsters and it isn't that far away from the standard size of 205/245 on S2's and turbos. The rear tyres would be so wide to handle the power and torque as well as the cornering forces, also manufacturers tend to make the front tyres overly skinny so you get some understeer before you get oversteer as this is a safer set up for non-driving enthusiasts as understeer doesn't take much skill or knowledge to tackle and the recovery actions required are intuitive to the non-enthusiast, i.e. lift off the power and turn more into the corner. If you do that in oversteer you are going to get yourself into more trouble very quickly!

 

[Fen]

What I was trying to say is that 225 tyres should be OK on a 7" rim based on what RS2 owners (and now Mik) have experience of. 245s definitely don't go on a 7" rim.

In terms of ABS John is right; the system is calibrated to "understand" how fast the front and rear wheels rotate relative to one another with the original tyre sizes. As long as you stay within the tolerance it has you can change the actual sizes to anything you want, but if you change one end and not the other then the difference goes beyond spec and the ABS flags a fault.

 

[Diver944]

ORIGINAL: jason

We think my appalling handling could be down to the Pirrelli PZero Assims on the front of my car.

Success!

I've just come back from an 80 mile trip since my Pirelli PZero Assims were binned yesterday and my S2s sweet handling has now been restored to it's former glory []. It's probably more to do with the dreadfully uneven wear rather than the brand of tyre themselves (they were from a S/H wheel and tyre purchase that didn't look too bad 6 months ago when I fitted them)

 

[jason]

Great news Paul - I've bought some Dunlop SP 9000s - lets hope I have the same success!

 

[Guest]

I've just bought one with 17's on and am about to replace the rear ones. they are 235 45 17 and i'm based in preston if your local we could get a deal on 4??

 

[geoffbateman]

Sorry, I'm down in Norfolk, but you might want to try etyres.com or e-tyres.com, I can't remember which it is. However, their prices seem very good. You order online and they come and fit them at a chosen time at your home, place of work etc to suit you. I haven't tried them myself yet as I don't need tyres yet for probably another couple of months but they certainly seem to be worth a look.