Tyre widths

[dredr62]

I have 19" Jaguar apollo alloys on my XK8 with 255/40/19 p zeros on the rear. I think, but am not certain, that the rear wheels are 9J. If this is the case would they be able to safely accept a wider 275mm tyre?

And would the fronts which I believe are 8J's be able to accept the 255mm tyre?

Any comments appreciated.

[mike020150]

The first question to ask is why deviate from the existing tyre sizes? Jaguar worked hard to specify tyre width, profile and diameter combinations that work well with the XK8's suspension settings to give good ride/handling and roadholding compromises as well as producing reasonably accurate speedo readings. Whilst Apollo wheel rims can accommodate a range of tyre widths, it's particularly important to consider the likely effects of wider tyres on those rims. If you increase the width, especially without changing the profile, the handling characteristics of the car will change by becoming less taut. If you do decide to go ahead with such a change, it would be best to consult first with your chosen tyre manufacturer's distributor. Tyre manufacturers produce car application data, usually held by their distributors, which show the range of safe tyre widths/profiles and diameter combinations for each model of tyre. Mike.