Can I fit a size 17" Rims on my car that initially came in a size 16" Rim? If so.....
Whats the best recommended tire sizes for both front and Rear tires(either way)?

 

Yes, it is called a +1 sizing. What is the stock size currently (I am not too familiar with it).

I use this site to check overall rolling diameter
Tire size calculator

 

I thought the S Types came with 17" rims stock.

 

Mine has 245/45/17.

I believe some were 16s as stock.

 

The '03 V8 models came standard with the "kronos" 17" wheels in the US (check my avatar). The V6 models had the 16's. Although, you could special order several different wheels when they were new. Believe it or not, each wheel has it's own name. Gotta love the eccentricity in that....

I have the original sales brochure, as well as the original accessory brochure from '03....so if you'd like a scan from the wheels section, let me know.

 

Maybe look in case they are already online... a lot are. I lost track of how many google found but it was a lot.

 

TireRack.com says the 2003 3.0 came with two OE tire sizes: 225/55-16 and 235/50-17. With the other OE tire sizes for the S-types that I am aware of, these are the OE tire sizes (except for the R rear tires):

225/55-16 (25.7-25.8" dia)
235/50-17 (~26.3" dia)
245/45-17 (25.7" dia)
245/40-18 (25.7" dia)
245/35-19 (25.8" dia)

So, any of these tire choices will fit and will be the same or very close to the same diameter as your 16" option. I have read that larger tires than OE sizes (either in width -- wider than 245 mm nominal size in front -- or diameter (larger than 26.X")) can rub.

Finding wheels to fit the S-type is more difficult. Without elaborating, your best bet is to find OE Jaguar *S-type* wheels (not just Jaguar OE wheels, but ones made specifically and only for the S-type -- others MAY fit but offsets and lug patterns vary a lot among Jaguars of the past 15 years), or maybe to get some Coventry brand (by TSW I think) aftermarket wheels that are made to fit Jaguars. I am looking at the Coventry Hornet silver (non-chrome) in either 18" x 8.5" or 19" x 8.5". If you just want 17" wheels, you can probably find some OE Jaguar wheels for sale by S-type owners who want to go to larger diameter wheels. Note that if the wheels are off of a supercharged R model (18", maybe 19") the rear wheels are wider (to handle the power) and require wider tires. You certainly don't need the staggered wheels with wider rears and it would be a hassle in that you couldn't rotate front to back, so I would stick with non-R-spec wheels.

When looking for wheels you also need to match the width to the tire you want to mount, and a good place to check is TireRack.com (no I am not connected to Tire Rack -- I have bought from them before and like using their data for fitment, tire size/dimensions, and the customer surveys and reviews and tests). In the "Specs" table for any tire, they give all the sizes and dimensions and then rim width in a range of sizes that will fit, and the measured width (presumably the rim width the tire is mounted to for the measurements of section width (widest point of the tire), tread width, and diameter). I would target the measured width wheel size.

Again, beware that you need to match (at least) three things for wheel fitment: lug/bolt pattern (how many lugs and what spacing), wheel offset (how far in or out the mounting surface of the wheel is from the centerline of the wheel -- positive offset (measured in millimeters) is normal with modern cars and means the mounting surface is closer to the outside/street side of the wheel), and centerbore diameter. (Also load rating but less of an issue with cars versus trucks.)

 

The S Type came stock with 16,17,18 and 19 wheel options. If you want to go to any of those sizes I would look for a used set of factory rims as these will fit for sure.
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