Hi

Pirelli are making the original P5 tyres again in the sizes 205/70R15, 215/70R15 and the 225/65R15 for the XJ40.

These tyres have been tested by Jaguar and have the J homologation

 

Yes, 260 euros !!!! The good choice is 16" wheel.

 

Hi Nasher,

Welcome to the Jaguar Forums!

Before posting in any more forums, please visit the New Member Area - Intro a MUST and post a required introduction so we can learn something about you and your Jaguar and give you a proper welcome.

As the availability of 15 inch tires for our '93 XJ40 dwindled, like Sovejag13190 and others I found it less expensive to buy a set of X300 16 inch wheels so I could use that far more common and affordable size tire.

Cheers,

Don

 

I suspect Nasher works for Longstone tires, the distributor of the products "see location"

Larry
Day 18

 

Good deduction, Larry!

All five of his posts thus far, in various forums, have been tire-related. I was already suspecting a tire connection, but wouldn't have thought of Longstone as a clue. You're a good sleuth!

Cheers,

Don

 

Hi

Yes i run Longstone Tyres. I shall go and post on the newbie board.

Yes 16" tyres are cheaper, but it is not all about price to everyone. The good news is that for those who want the Pirelli P5 it is available.

I have had a variety of arguments on t'internet before on this subject, which i shall try to avoid having now. However, an appropriate tyre for a car works better. You are sacraficing some comfort with a 16" wheel by having less tyre side wall and a more modern stiffer carcass and flatter side wall.

Worth noting that when Jaguar took the unusual route of asking Pirelli to develop a spacial tyre specifically for their cars, if they thought 16" tyres were t he answer that is the route hey would have taken. However they chose to stick to the taller tyre side wall and the 15" wheels.

 

if jaguar put 15 "it is because there was the 390mm and because the rise of the time was recommended in 15". After optional there was the 16 ". I think there is no point putting 15" at this price.

 

Hi Nasher,

Thank you for disclosing your association with a commercial vendor. Note that the forum rules expressly prohibit promoting your products in model forums or without entering a Sponsor or Vendor agreement with Internet Brands. Please read the information at the following link:

https://www.jaguarforums.com/forum/m...efore-posting/

Cheers,

Don

 

Hi

I have now entered the Sponsor vendor agreement thingy. However It is not my intention to do blatant advertising on here i hope you will find my posts informative. However i will dispute posts like this:-

Yes, 260 euros !!!! The good choice is 16" wheel.

I don't think Jaguar went back to 15" wheels because they had some lying around. I think they did testing, and it was better on 15" wheels fitted with the Pirelli P5 https://www.longstonetyres.co.uk/pir...ezione/p5.html than it was on 16" wheels.

Yes jater Jaguar did fit 16" wheels but i would bet my favourite pair of underpants that they changed lots of the other elements of the suspention and steering, more advers camber, more caster, stiffer springs, self leveling suspention, cleverer power steering, etc.

I don't think it is the right way to go, to start buying new wheels and changing other parts of your car. just because it enables you to buy cheaper brand tyres. I realise that obsolete tyre sizes made to the best quality by the best brands adds up to a large credit card bill. However spending money on wrong wheels to make you car not as good so you can buy cheap tyres doesn't make sense to me.

How much are you paying to buy a 16" Pirelli or Michelin?

 

The 1993 - 1994 XJ40 cars had 16" wheels and there were little or no major changes to the suspension or steering system.

 

when you say there were little or no changes. do you mean they did some subtle changes to the camber and caster angles and adjusted the suspension or not? i suspect they did, because that is what car manufacturers, and racers do to make the car suit a wider foot print and a different side wall height.

 

There were some revisions in suspension parts, beginning during the early years, but the revised part numbers supersede for all XJ40s, regardless of wheel size. The only really substantial revision was the change from the stamped steel rear lower control arms to the cast iron arms. This change occurred on the late '94 cars and was carried on to the X300.

This can be confirmed by reviewing part numbers at jaguarlandroverclassicparts.com.

Cheers,

Don

 

Misters Nasher and "Longstone Tyres"
Basically what we are saying is your predictions of doom and gloom for XJ40 owners switching from Jaguar 15" wheels to later 16" wheels on their cars is just a lot of hot air.

 

What i'm saying is that the tyres that Jaguar decided were best on their cars, are the tyres that are best on their cars. and as they modified the suspension and steering as it turns out they did, then the tyres change marginally to benefit the subtle changes that jag made.

They did tons of testing. they could have fitted what ever tyre they thought was best. And i don't think we know better than they do. The current P5 range are J homologated.

 

Hi Nasher,

To what specific suspension and steering changes do you refer? So far as the Technical Introductions and parts diagrams show, no changes in geometry or other relevant changes were made from the 1987 XJ40 through the 1997 X300. Sport models had shock absorbers/dampers with higher damping rates, and some had steering racks with fewer turns lock-to-lock, but otherwise the rest of the suspension was virtually unchanged for 10 years. The only significant change was converting early cars with Self-Leveling Suspension to conventional shock absorbers/dampers, but spacers and other components were provided in the conversion kits to maintain the same geometry. And Jaguar sold 15", 16" and 17" wheels for these cars with no change in suspension geometry. I can personally attest that replacing the original 15 inch wheels on our 1993 Vanden Plas with 16 inch wheels from an X300 significantly improved the handling and steering precision with very little change in ride.

Regarding the brand and model of tyre Jaguar fitted, we all know that Jaguar had a longstanding marketing relationship with Pirelli (just as Formula 1 do now). Historically, Jaguar has entered such agreements only with top-tier companies (Lucas notwithstanding), so we can be sure the Pirelli P5 was an excellent, world-class tire in its day, competitive with similar offerings from other leading brands like Continental, Michelin and Dunlop (with whom Jaguar has had marketing agreements since before the Le Mans victories of the '50s into the '00s).

I truly mean no offense, but those of us who have owned XJ40s for a couple of decades and have gone through several sets of different brands of tires on different size rims know that there have been and currently are other tires that perform as well or better, depending on the driver's satisfaction criteria. The all-season tire Jaguar selected under a 1970s marketing agreement may or may not be the ultimate option today, given the advances in tire construction, materials, tread design and economies of scale.

All that said, I am happy that Pirelli is once again offering the Cinturato P5 for the XJ40. More options are always better!

Cheers,

Don

 

As a former mechanic with a history of different brands, personally I wasn't a fan of Pirellis. I had a set of Conti DWS 06 in 225/55/16s on my XJ6 and really liked them.

my .02

 

My XJ40 originally had TD220's fitted when I took over ownership of the car. I replaced these with genuine Jaguar 16'' Lattice alloys shortly after and fitted Pirelli P7 Cinturato's, 225/55/R16.
I've run these on the car for over 3 years now and find them to be perfect for what I desire - a compromise of comfort with some sporting quality.
It's also worth mentioning that the late Jim Randle's personal car is fitted with the same setup.
To me that speaks volumes.

 

Who is Jim Randle?

 

Lead engineer of the XJ40.

 

Henry,

Welcome to the Jaguar Forums! It's great to have you with us!

To other members I recommend you check out Henry's photo in his New Member Area introductory post. His XJ40 is gorgeous!

Cheers,

Don