What have you Modified?

As I’ve been spending some time reading through the forums here and Kirby’s book I see there are a plethora of modifications that have been done or suggested for our cars. Although it’s almost a pub style question, what mods have you guys done to your own cars and why?

I’m rather interested to see where people have strayed from the original design and how it has been living with the completed mods. It’s like show and tell almost, plus I think there may be some hidden wisdom here on small functional improvements that may not have been shared yet or people didn’t think worth mentioning.

I guess I’ll start it off, I have an '87 coupe and have done the following:

-added coolant filters
-changed to 16" jaguar turbine wheels
-reverse manual valve body, with engine braking
-ratchet shifter

There is more planned but to be fair let’s keep it to things we have completed and have experience with.

I’m interested to see what you guys have done to make the cars your own.

Surgery on inlet filter cans. Great sound on WOT.
Removed centre resonators. Better exhaust note.
Twin electric fans. Very quiet on start up.
5 speed manual transmission. Maximises benefit of “revvy” V12
Convert to MS3Pro ECU. Unknown. Currently under commissioning.
The mods go from easy to less easy.
The increased aural feedback is great. The manual transmission also great. The V12 is limited by piston speed at 8330 rpm so the occasional burst to the 6500rpm redline thru the gears is aurally and physically exhilarating!!

5-speed manual, unbelievable difference! have converted several vehicles to standard shift, always a performance advantage but it was a HUGE difference on the jag! 3.31 gears helped but a little lower would help more. opened up the air filter inlets/trumpets and installed could air ducts. I was surprised but can tell the difference. removed all the pollution crap, noticeable difference and well worth the time. European down pipes (no cats) into lake pipes, not so great for a daily driver but sounds great and believe it helped. sure seams faster with the straight pipes but probably going to add some type of mufflers as ‘cool’ changes to ‘annoying’ fairly quick.

Idle air valve by passed
leaper hood ornament
by passed carbon canister valve
removed gas sump tank in trunk
Convert alternator to GM.
customize headliner.
add electric fan for cooling radiator
polyurethane rear motor mount
possible hood vent

As far as bodywork is concerned,
Changed rear axle to floating dually, strengthened underneath of car. So had to make much wider fender flares retaining original lip on exterior.
Pressed hood louvers
Fender vents as well
Modified windshield
Modified gullwing style door
Changed the growler emblem to an image of my own cat.
Side exhaust pipes w glasspacks
1100 panel mounted rivets
And some other bits to personalize.
I have owned several xjs most my life and appreciate them in their stock form but decided to make it more utilitarian which is why I started using for towing.

JamesLove…Do you recall what you were charged to press the louvers into the hood?

probably better to ask what i did not modify!

some pix,

Euro down pipes, ceramic coated manifolds and downpipes, 2 1/4" dual under rear diff, magna-flow mufflers and cats.
Dual electric fans, completely re-wired, removed latching ckt, installed lower temp thermo switch
Water temp and oil pressure gauges
Shift kit in TH400 - anybody wanna buy a perfect TH400 in about 3 months? 55k miles.
GAZ shocks
Coolant filters (not worth the hassle as they never catch anything, peace of mind I guess.)
Gear reduction starter
Lots of under-hood cosmetics
Fuel pressure gauge on main feed line
Replaced stereo and speakers
In process of 5sp conversion, will be t5 with 3.54 final drive.

Aluminum Rad, elect fans,filters, SS water rails
TKO 600 5 speed, Alum. flywheel , gear reduction starter
3.54 diff
Auto Meter oil press & 2 water temp gauges, Fuel pressure gauge
1" front & 3/4" rear sway bars, springs, Bilstein’s, poly bush’s, handles great, ride’s like sh%t.
Euro pipes, Power Effects adjustable(sound) mufflers
Dayton wires
Vented rear inboard rotors
Gold hood growler
Harvey Bailey Front “X” brace
Lutz 1

I don’t recall. However it wasn’t anything that will break the bank. Find your nearest machine shop and find out if they have a press capable to make what you want. In my case I wanted it similar to the E type. I also bought aluminum ones before I decided to have pressed if your interested in those you just rivet them on.

One day you need to show us some pictures of the dually set up, in still thinking about it since last time you mentioned it. Never going to do it myself but it sounds so cool

  1. Yeah, I’d like to see the pictures of that XJS dually !!! The other day, I went to the pharmacy to get stuff. Oddly, “?” no pharma or related!!! An Isuzu box van was parked along side.
    I looked at it’s set of duallies. I thought of this one. Yeah, they are smallish. Surely not the big truck 10.00 or 11:00 variety. That would be grotesque !!!

  2. On Point: My car is not an XJS, but a SJ wuzza 6. Big mods:

  3. Lt1 V8 and 4l60E transmission. A great car, even better.
    I term it, English elegance with an Italian flair and American power.

  4. XJS lattice wheels replace the original Kents. Look like they belong…


I’m still finishing some body work but these are some older pictures I have shared several months ago. Will be done with the vision in less than 3 weeks. Also pics of modified classic bumpers from a 1960 mkx I will be using on her.

Thanks! It is super cool I really like the whole look of the car you’ve got going. The rivets seem to recall a fighter jet in my mind. I know your calling it a utilitarian build but I think it’s pretty stunning visually as well. Well worth the wait to see it!

1 Like

All chrome trim black powder coated cold aire induction KN filters Lutz Stage 1 cooling system mod kit rear IRS vented rotor brake kit IRS torsion bar kit Trans mount modified hanger cat back under pipe kit w pass thru silencers heated 02 sensors uprated injection harness 3rd wire to alt to firewall buss add bleeder vent to cooling system solid copper ign harness Led light system upgraded Walnut Burl trim Mardi steering wheel AFM 16in wheels sport t50 rears Boot spoiler. Not a dust catcher replacing 30yr old electric connectors wth Deutsch plugs 2xl wire silicon vac tubbing firewallto front injector harness Lutz Lift Plate at Irs for easeof service to rear yres 225\50\16front245for service to brake bleeders Speed bleeders silicon wiper blades silicon cooling system hoses Looking for HUD display that is not sticking out of the dash pad rear view camera for reverse and HSP note driving upgraded sound system looks stock vented hood for better under hood dispersion power steering coolerstillworking on perfecting a great machine Best JW

IRS torsion bar kit

OK, I’ll bite: What’s an IRS torsion bar kit?

– Kirbert

A kit that allows the installation of a Torsion Bar at the rear of the machine on the Independent Rear Suspension system without having to drill or weld ears on the Trailing arms, it also includes adjustable torsion bar links for different settings as required. Works like a champ and solves several problems. Thanks for asking, best, JW.

I apologize for the run-on sentences, poor spelling, lack of spacing and punctuation as I sent that text from my new I-pad and am unable to figure out the total system as yet. Best, JW

A kit that allows the installation of a Torsion Bar at the rear of
the machine on the Independent Rear Suspension system without having
to drill or weld ears on the Trailing arms, it also includes
adjustable torsion bar links for different settings as required.

Are you talking about an anti-sway bar? Because that is NOT the same
thing as a torsion bar!

– Kirbert

Very nice. …can you tell me. …is the tank handmade. …how many gallons …do you have the sump tank. …what brand and number is pump…what about spare tire. …