I have a 2006 Super V8 Portfolio that has 20" rims with currently, PILOT SUPER SPORT tires, which are noisy and don't take bumps well and had many flats within their 20,000 mile life. I'm thinking of going with a touring tire that fits my 20" rims. Does anybody know if its worth it or should I just put a set of sport tires back on this car?

Nice ride! Pilot Sports come with a pretty wild cost and treadwear premium, not to mention noise as you said, particularly for a car like this. I personally would (and did) get a set of Continental all-seasons. There's a few different flavors.

I have the same car.
When I bought it, the PO had already fitted 255/40 ZR20 Michelin Pilot A/S tires exactly for that purpose: to avoid flats and rims damage, and get addtional smoothness.
That tire dimension has a substantially taller profile, I attach a pic showing it compared to a used Falken in the original 255/35 ZR20 dimension.Of course there is a slight deviation in the speedometer reading, but unnoticeable for practical purposes (at 130 km/h on the speedo, the GPS now reads a true 130, while previously it was 125). Also no rubbing in whatever conditions.
Since then I have made 60.000 km on that set of tires, perfect handling for my taste, no issue at all and they still look good.

I'm jealous of your 2006 Portfolio! Just looking at them. Bought a 2009 Celestial Black Portfolio a month ago, but now wondering if I shouldn't have been looking for a 2006.
In any event, I put a new set of PIRELLI CINTURATO P7 AS NCS tires on it. I have Pirelli Cinturato P7 AS tires on everything I own and would be afraid to try anything else. They are very quiet and comfortable and perfect for anything not "tracked". The latest NCS was all that was available at Discount Tire and they have foam blocks glued inside them for noise cancelling. Haven't put enough miles on it to tell if they are quieter than the regular P7. But, I have no qualms recommending the Pirelli.

Just wondering if I were to go with the 45 as opposed to the 35, and they make them in All Season Tires, too, would I have to mess with rising the car, with the computer/air shocks or something, so to avoid tiring hitting the car?

If it would be 255/45 ZR20, it would be way too big!
255/40 ZR20 is already quite large as you can see on the pic

When I got my car, it had 245/40-20 tires fitted. It may have been that the correct size was not available for the previous owner at the time. They were quite worn and I obtained the correct 255/35 - 20 tires when I had the badly kerbed Callisto wheels refurbished. I found that the correct size wheels give a speedometer error of about 6 Km/h high at 100Km/h, comparing with GPS. I set my cruise control for 110 Km/h as there is a number and graduation there on the Japanese Km only speedometer, and GPS says about 103 Km/h, which is fine with our national 100Km/h limit.

You can compare the dimensions above.
It's interesting to see the discussion about Michelins and Pirellis and Continentals. In this country, all of those brands cost several hundred dollars each, making about NZ $3000 or more per set. I'm not sure why they are so expensive here, but this is a small country so the small numbers we import may increase the price.
You may laugh, but I got a set of Chinese Triangle tires for about $150 each. I have just got back from an 18 day 2000 mile trip from Oxford in the middle of the South Island to the top of the North Island and back. The tires performed perfectly. Sure, they are noisy on our coarse chip roads, but perfectly quiet on smooth tarmac. They seem to have plenty of grip, wet or dry, and I have never had the traction control light on or any feeling of lack of control. We have a fairly low speed limit, so they don't see much time above about 150 Km/h, and up to that only when passing semi-trailers.


Triangle TH201

Correct spec for car
I figured that for the price they were worth a try, especially given the price in NZ of 'name' brands.

Pete

Hey Pete,
​​​​​​Next time you're tyre shopping, have a look at the Atturo. I found them to be quieter than the triangles and they have a thick rim protector lip on the sidewall. Had some bottom of the barrel 'kinforest' tyres when I got it - they were lethal in the rain.
Running 255/35 and have wondered if I could fit something a bit taller profile in there to help with our rubbish roads.

Nice looking tire, how do they compare, to name brands, in mileage ratings & price?

Hi Keltik,
I was going to ignore your advice as being from the U.S. , but I see you're in NZ too! I will check out the Atturo next time, the Triangles are a bit noisy on coarse chip. As above, the 245/40-20 are a bit higher in the sidewall, but the 35 profiles look really good with 20s.
What is your car, and where in NZ are you?
Kind regards.
Pete M

Hey now!

Please, no offence was intended, but the tires marketed in the USA are generally very much cheaper than in this tiny outpost of the former British Empire / Commonwealth. We hear about people buying Continentals for a couple of hundred dollars, but for us they are about NZ$800. $1000 each is quite possible in some sizes. We are envious of your economies of scale, and your large number of Jaguar enthusiasts. The size of your country is staggering, I visited several times in the past. A recent trip I drove in New Zealand of 2000 miles, covered three quarters of the length of our country and back again. That's smaller than almost every US state!
Wishing a very happy New Year to all American Jaguar drivers!

UPDDATE:

I replaced my Michelin PILOT SUPER SPORT 255/35 ZR20 tires, with Continental 255/35 ZR20 97Y Extreme Contact All Season Tires. Was going to get what, paydase, recommend, 255/40 Pilot Super Sport, but the Continental Extreme Contact was about $100 less per tire, plus Michelin left a bad taste in mouth. I been driving on these new tires for over a month now, and have to say, it’s like I’m driving a different car!!! The ride is like, I would expect from any nice car - No more worrying about each road this car drives on!!! I was wondering if this car, out of the show room, came with the Michelin Super Sport tires, because if they did, it was the wrong tire for this car, period!!!

-Art

I believe the factory tires were Pirelli.

Jaguar and Land Rover have also used Continental tires from the factory on various models and model years.