I'm currently rolling on stock 18's on my 2004 VDP. Ride quality is great.
Now looking at a 2007 Super V8 with the stock 20's
Was wondering how much worse the ride quality is.
I live in LA so lots of uneven surfaces, cracks in the road, pot holes, etc.
Appreciate any feedback.

 

The 20"s will loosen any tooth fillings you might have. Take my advice, and spend the money on something else on the Jaguar.

 

I think people like them if they think the 20s "look better".

They'll be a LOT harsher.

 

Mine's on 19s and I've got myself a set of 18s for when the current tyres are done. Our roads are getting worse by the year and I'm beginning to think a set of 17s would be even better (17s were early option but were dropped early on).

Remember that 20, 19, 18 & 17 are wheel diameters, so dropping down 1" is only half-an-inch (radius) inwards on the rim; hardly noticable to the casual glance I would have thought

 

Interesting about the above comments, funnily enough when I specified the wheels on my X351 when new I specifically went with the standard 19" wheels as I had read about the 20" were much harsher on the forums.
However ........after 6 years of running on standard 18" rims on my old X350 I traded the car for a Super V8 already on 20" Sepangs, agree they look brilliant but I was initially concerned about the ride.
Now the Super V8 is on comfort suspension unlike the XJR and I was really surprised that the difference was no where near as bad as I was expecting.
I do put 18" rims on with winter tyres so I can do a direct comparison a couple of times a year just after or before change over.
I actually find the difference is marginal unlike some of the other guys here, I do carry various passengers in the cars and have not had any bad feedback about the ride quality.
I have never thought about changing the wheels on the X351 though as I am perfectly happy with ride and appearance.

 

This is not comparing like with like. The X351 is a different car, and whilst the suspension is similar, (but coil spring on the front), Bilstein may have done work to alleviate the harshness on later cars. When I bought my previous X350 in 2010 it was on 20" Sepangs and the ride was really harsh, compared to the Rover 75 I had previously. I was offered a no-charge swap to 18" by the dealer after about 2 weeks and took up the offer. This made the ride a whole lot better and I then drove the car for 85k miles until I part-exed it for my current X358 Sovereign. That came on 19" wheels and the ride was harsher than the 18"s so I bought a set of five 17" Elegant wheels on e-Bay. These give a much more compliant ride and I am now totally happy with the car, but in terms of ride comfort, the Rover was well ahead.

Our roads here in the UK are really awful and maintenance, altough now improving was neglected for many years. In comparison, German roads are like billiard tables. Maybe as Bilstein are a German company, they cannot imagine such neglect in a rich country that we are supposed to be.

 

I did compare line for like as I am using summer wheels which are the Sepangs and winter wheels which are the 18" luxury on the same car, the Super V8, so it was interesting you found your Sepangs were harsh. I have the comfort suspension and using Falken tyres so maybe that is why mine is fine

 

I don't have any issues and I'm currently using 20" rims & proper sized tires per the label on my Jag but I have the coil over conversion.

 

I had a 05 with stock tires and wheels (18's I think) that road like a dream but now have a R with the 20 inch Sepangs and it rides harsher. I love the wheels and because its an R I don't really care. If it was a Super I might though as all of my past Jaguars rode like a dream except for my last XKR which again had sport suspension.

 

I have had a number of wheels/tyres combinations on my X350 NA and my current Super V8, from 17" to 20", summer and winter tyres.
Fact is that the quality of the ride also strongly depends on the tyres and suspensions set-up, not only on the wheels diameter.
Currently I run 255/40 R20 Michelin Pilot Sport A/S Plus N0 (a Porsche spec, not the standard one) that behave beautifully on my Super V8.

 

Sorry, misunderstood you. Maybe its because I'm getting old or something ! Anyway, each to his own. I'm now happy with my car, and you're happy with yours. I just wish we didn't have all this current motor car zeitgeist of "Sport, Sport, Sport, Sport". We are not all wanting to drive round Silverstone every weekend.

 

Won't be the best of rides

 

What is the best/good after-market wheels for a 2006 XJ Super 8 Portfolio - 255/35ZR20? The original wheels have three bent rims. Or, is there a good place to buy refurbished wheels? Jaguar wants $2,100 for one new rim <grin>

 

Sometimes (rarely) there are used Callisto's selling on ebay.
New Callisto's (if ever you can find them) cost indeed a fortune.
I think the best is to refurbish the damaged rims anyway.

Then either you keep them on the shelf and purchase cheaper compatible 20"s, or you go down to 19"s or you increase the tyre flank height, as I did with my 255/40 R20's, I am very happy with.

 

Paydase- You didn’t like the original 255/35ZR20 tires? Why? I can’t tell if the new tires I bought will give me a good ride, because if I go over 50 mph, the car creates allot of road noise, hopefully caused be the bent wheels. What are the brand name of your new 255/40R20 tires?

 

When I bought my SV8, it was already equipped with these "upgraded" tyres.
The PO told me he put them because he feared possible rim bending due to potholes.
The 35 profile is indeed quite slim while the 40 profile is equivalent to what you have on 19" rims.
I have now driven 25.000 km with these tyres with no flat and very good comfort.

Only issues with a 40 profile is a slightly increased rim perimeter that may be unacceptable by MOT (Technical Control here in Belgium, but I passed through), hence a negligible modification of read speed on odometer (but actually the speed now reads exact, as controlled with GPS), and a possible feeling of heavier steering/handling (that I did not notice).

 

I have the 20" Sepangs on my XJR. If I had the choice I would not use them again, they are harsh on sharp or short bumps. The ride is fine on dips and things like that but you will feel potholes and probably bend a wheel eventually.

 

Doubtful that would be the rims. Tires can be loud @ freeway speed. Michelin Pilots were too loud for me and I'm hearing impaired Aleather. Others find them very quiet. I have Bridgestone Pole positions on my XK but XK's aren't quiet anyway so I couldn't tell you if the tires are quiet at highway speed.

Also, some weighing in aren't here in the U.S. I don't know if the tires made in other parts of the world are made of the same material? Can anyone enlighten me?

Road surface material is also a factor on road noise, different types of bituminous, age etc. All different State to State and county to county. So what might be quiet for me may be ridiculously noisy for you. That's why reviews vary so greatly I assume.

I know you're looking to by new rims. If you want a quiet and smooth ride, go with 18" wheels, that will get you smooth and the higher profile will impact noise. I went from stock 19 down to 18 for that reason. Brand and type of tires, including rating will also affect noise.

If you can't do without the added beauty of the 20" (I get it), prepare to keep on paying for them. There's a reason 3 rims are bent and it's not just a jag problem.

Yikes - too much to think about. Good thing I'm deaf and growing deafer.

 

Sean W - Well, I know I’m in for trouble keeping the 20” wheels, But I found a place that straightened two of the wheel and I put the spare wheel on the car, so now I only need one refurbished wheel. I found a couple refurbished wheels that are Callisto 9x20 and the chart that you gave me said my car takes Callisto 8x20 wheels. Would it be bad to put the Callisto 9x20 wheel on my car. It seems that both 9x20 and 8x20 wheels takes the same 255/35XR20 tires???? Is their a parts break down from Jagaur telling me what the size wheel I need. I did write down all the numbers that was on the backside of the wheel I need.

 

yes it would be bad unless you put two 9" in the rear.