Changing 17" rims to 18"? How will this affect my car?

[Ladams]

I have a 2003 S-Type Sport 2.5 V6 which has the standard 17" alloy wheels as supplied. I am considering fitting 18" rims for two reasons, first because I think it will enhance the appearance of the vehicle and second because the last time I bought tyres I was told the size is no longer "in fashion" and therefore the choice and availability is restricted. With the 18" rims I will have a wider choice as I would use 245/40/18 which is a more readily available tyre size.

My question is, will this adversely affect the handling / road noise / comfort of the car or will I notice little or no change?

Also. if it is ok to go to the 18" rims, is there any particular tyre I should choose. I presently have Firestone Primacy 3 on the 17" rims and I like them a lot. I don't buy "budget" tyres, so cost is not important, I just want the best for normal day to day motoring with some motorway use and good grip in the wet. I drive fairly sedately rather than spirited!

My thanks in advance for your help.

Les.

[oldtimer]

Les,
For what it's worth my 03 V6 S type sport is fitted as standard with 235 x 50 x 17 tyres

[Montana5]

Hi Les and welcome to the Forum. Have a search on some of the Jag Forums, I know that some people say moving up a size has a detrimental effect on the ride. The other thing to consider is your Insurance, you could ask them and see how they stand on upgrades, many Insurance Companies are looking for the slightest excuse not to pay out on claims nowadays. Personally I believe whatever size of Tyre Jaguar fitted after all the testing and loading carried out in the developement stages, then that's the best for that Car.

Doug.

[J44EAG]

I`ve driven cars with all sizes of rims. All behave slightly differently.

I originally had 16" on both a V6 then a V8. They had soft comfort dampers. That combination was unpleasant to say the least. The 55% tyres would bang and crash over cats eyes and bumps. The ride was undulating and even in town, the car had a marked tenancy to understeer. Overall, the small rims ruined the ride of the car.

19" rims greatly improved matters with 30% tyres. The ride improved to my astonishment. Later gas Bilstein sport dampers were fitted and the ride changed for the better.

I see no reason why 18" might not sharpen things up for the better. 18" is a good compromise in my opinion and will help you stay away from the issues of over thin tyres that start to be present with 19" rims. If 18" tyres are more easily obtained, that can only be a good thing.

The various rim sizes were offered from the factory as options with Sport models having the larger rims as standard. I would only fit OE rims to ensure they remain as a standard specification to the car. It is unlikely that insurance premiums would increase as fitting OE spec rims of a larger size when new, never had any impact on insurance groupings.

Mike

[Montana5]

Its still a modification that differs from the original spec of the car.

Doug.

[Zennan101]

Hi Les,

Wise words from Doug. Better to ask the question of your insurers before any changes are made that take the car away from standard rather than argue after an event. Mike K is almost certainly right that different rim sizes when the car was purchased made no difference to the Insurance premiums but that was when the car was being delivered 'new' by the manufacturer to the first owner. Later changes may be scrutinised much more carefully. If you ask the question you know where you stand.

Rod

[Ladams]

Thank you everyone for your comments so far.

Following your advice, I have spoken to my insurance company and because the vehicle had an option of fitting 17 or 18 inch rims when new, there is no insurance issue as they are still within manufacturers original specification, except of course the value of the wheels themselves and there would be a small charge if I wanted to cover them against theft.

I would expect there to be a slight change in ride as the tyres will be a slightly lower profile and stiffer wall, but as 18" rims were an option when new, I am guessing the shocks and suspension not to be too stressed by the change, so I think I will go ahead. If after fitting I am unhappy I will of course report this on here for others considering changing their wheels. If they are fine with no adverse effects, I shall also be happy to keep you all informed!

Thanks again.

Les.

[Ladams]

Les,
For what it's worth my 03 V6 S type sport is fitted as standard with 235 x 50 x 17 tyres

Thank you, yes those are the type fitted to the car at the moment.

[jeff1954]

Am I right in thinking, larger wheels the tyres have to be lower profile to keep the rolling radius the same.

Jeff

[J44EAG]

That is correct, Jeff.

I had that issue to sort out when I fitted 19" ex X350 Custom rims to my old V8 S-type battle hack. From memory, I fitted 245/35/19 which equated with the same rolling length around the tyre as the previously fitted 16" rims. My local tyre guy sorted that out for me.

Mike

[oldtimer]

Les,
I shall be interested in your opinion after you have driven a few miles on the different tyres and rims.

In contrast I tend to drive in a more spirited fashion than you tell us you do. I recently went to our Jaguar breakfast club leaving early on Saturday morning when the roads are nice and quiet. I might have the timing wrong, it could have been lunch time as one of the clocks said it was One Twenty ! The road then reduces from dual carriageway to country A road which makes for interesting driving.

I must be the most insensitive driver ever because I happily live with the 235x 50x17 Pirelli tyres as originally supplied but could do with the extra two cylinders at times.

Give it an Italian tune up - do it a world of good

Happy driving

Oldtimer

[davidr]

Oldtimer - did you buy your car or steal it? You certainly drive it like you stole it!!

[oldtimer]

David R,
I told you that in confidence now you blurt it out to everyone

[Ladams]

Hi Oldtimer,

The rims are now fitted and look very nice I think, they have changed the character of the car completely. I have also added an "Adamesh" lower front mesh grille, smoked side repeater indicator lenses and some chrome exhaust trims, all from the same supplier. I have also ordered a mesh front radiator grille but I am waiting for that to arrive as they are spraying the outer rim to match the car. I

The wheels make an incredible difference aesthetically and the ride has changed slightly. There is a little more tyre noise at speed and the ride is slightly firmer, but not enough that it is a problem and I think only the driver would notice. My lady couldn't feel any difference as a passenger. With the standard wheels I had Firestone Primacy 3 on the front and Faulken on the rear which were about down to the tread wear markers. With the new new Firestone sport tyres the car feels more responsive with firmer, more positive grip in the corners. Whether this is just because the tyres are brand new or if the 245 width (as opposed to 235 on the factory wheel) has helped, I don't know, but once the tyres had bedded in the ride was an improvement. The wheels and 245 tyres certainly make the car look more aggressive as they now sit only just inside the wheel arch giving it a "chunkier" appearance, which i like. It has certainly turned a few heads already and had admiring glances I even had a chap approach me in a car park to ask me if I wanted to sell it! I declined his offer

As I said previously, I am not a spirited driver ... that all had to change when I accumulated 9 points on my license ... 6 of those have expired now but I am enjoying driving slower. My thrill comes from the enjoyment of driving a car that makes me smile when I look at it

Regards, Les.

[oldtimer]

Les,
I have to say both the new wheels and car looks dead smart - well done. The points on your licence is a bit of a "bummer" I 've attended a couple of these speed awareness courses, saved me licence but what a waste of time !
I'm pleased you are satisfied with the ride quality, thanks for the info.

Now for the serious stuff. I hope you have had time to read the extensive amount of stuff written on the S type board. In particular, in respect to corrosion. Many of them are failing the MOT due to corrosion and in particular sill corrosion. So, I would encourage you to have the plastic sill covers off and inspect the metal sills beneath . You may of course tell us that this has been done and has been Wax Oiled for preservation