I have been thinking ever since I got the car that I should buy a set of 18" wheels over the 20" wheels. I want a mroe comfortable ride but I also want a mroe composed ride on the back roads in the UK. Do you think the 18" wheels will make an improvement or not? I am looking at a set of the Hydra 18" wheels that should fit with the Brembo brake calipers. I'm also not sure if the 18" size will give enough grip in hard acceleration compared to the 20" wheels as grip is already lacking at low speeds?

 

I've had a 2001 XK8 on 18" Impellar and a 2005 XK8 on 20" Sepang. The 20" gave a very harsh ride and were more susceptible to damage. Since then I've had a 2007 XK on 19" Carelia and my current 2014 XK on 20" Kalimnos. Again the 20" gives a harsher ride and I've had to replace one through pot hole damage.

My preference would be 19" for the best compromise between appearance and comfort. I'm not sure 18" Hydra would fit with Brembo calipers but others may have direct knowledge of this combination.

Graham

 

18" Hydras most definitely fit over the Brembo calipers, both from the perspective of inner wheel diameter and clearance behind the spokes (direct experience).

In your evaluation, don't forget wheel weight. Unsprung weight contributes a lot to a harsh ride.

My car initially came with a set of (chromed) 19" Apollos. These wheels were heavy and I did not care for chrome. I upgraded to painted 18" Hydras: a much more comfortable ride all around, cheaper tire, and less likely to be stolen if this is still a thing.

With a rapidly aging car in the lineup, there is no denying that Jaguar managed to come up with pretty spectacular sets of 20" wheels for those last couple of years. These wheels are also somewhat wider, allowing a wider tire and therefore marginally more grip.

What wheels do you have now?

 

I have the 20" Detroit wheel and although I like the look of them the ride comfort isn't what I expected from a Jaguar. I have Michalin Pilot Sport 4S tyres on which I like a lot just not so much the price tag. 18" wheels should have cheaper tyres and a more comfortable ride, I just don't want the grip to suffer much if not at all because at low speeds it's easy to loose grip in the R model.

 

I believe there is pretty much a consensus the 18" wheels will give you a noticeably nicer ride.

Keep in mind there is what you want and then there is what is available. Our cars seem to be in the low demand and low supply part of the chart. There is an argument to be made that if you have your eyes on a decent set of Hydras priced ok and you can see a plan for them, just get them. That opportunity might not come along for a long while. Once you settle on a final set of wheels, whatever set is left will probably sell well anyway.

 

I don't plan on changing them until the tyres on my 20" wheels are toast. I paid too much for them to replace them now. My 20's need refurbishing anyway so whichever one needs changing first will mean I go with the 18" wheels I think. I will probably buy the 18" wheel Hydra soon ish, probably after my next service just incase I'm left with a big bill.

 

I have done this wheel/tire swap a couple of times. In my experience, cosmetically good wheels with ok tires sell well because people can install them right away, and deal with refurb/tires expenses later. Wheels alone (or with worn tires) are way harder to sell because now you are selling a project, people add up the numbers (these wheels plus new tires, shipping, mounting balancing) and most bail out.

IOW, don't wait too long if you want to sell the easy way.

 

I might think about it sooner then. There are a few sets on Ebay in perfect condition so I don't think they will run out anytime soon. I need to save up a little first because I just got the Adamesh exhaust and I have a driving holiday coming up.

 

I have the Hydras and can confirm they do fit the Brembo’s. I would gladly swap with you, but the roads here are so bad that a set of Detroits wouldn’t last more than a week.

 

I have 20" on my XKR now and I feel the pain when hitting bad road patches around Albany, NY, where the car is now. More worried about that car than comfort to me. Imagine the larger sidewall would certainly absorb more impact. Its all a trade off.
BTW, love this quote/truism: Owning an XK8/R is an act of love, not practicality. - mjlaris