1986 Jaguar XJS V-12 modifications

There are NO super/turbo charger kits for a Jag V12. Anything you do in that area has to be fully custom, meaning huge dollars (think $50k or more). Proper headers don't fit in the space available. Cat back systems are available from 2 sources I know of: AJ6 Engineering in England and Keisler Automotive in Tennesee. There may be others.

Stevo

Chris,

The first thing you should do is go to Jag-lovers.org and download "The Book" by Kirby Palm. It's a free download on the web. The Book is the bible for XJS owners. It is essentially the accumulated wisdom and experience of XJS owners from all over the world, compiled and edited into usable format by Kirby. You will find much useful information there about how to get more kick from you kitty.

Next, read the article in the tech articles section on this website that was written by Wayne Estrada. Wayne has compiled a very usable set of recommendations on how to get the most from an XJS. You can also "google" Wayne's name and find his website. He's got a lot more information there about upgrades that get more power and performance from these big cats. Wayne's suggestions run from the simple (K&N air filters) to the complex and costly. You can pick and choose how much you want to do with your car to get a few extra HP.

One change I would suggest (I did it on my car when I owned it) is to remove the mechanical fan and replace it with an electric, tied to the aux. fan relay. The mechanical fans are prone to failure anyway, so it's a safety issue as well as freeing up around 20 hp. I used a Permacool 18" fan from Summit Racing (NAYYY), which fit in very nicely. And consider the shift kit for the tranny and the bigger bore exhaust (without CATS if you don't have to pass emissions testing). Louvres in the bonnet are a nice touch to help remove the heat (I saw an application with 280Z hood louvres installed that looked great).

And if you want to go all the way, talk to people like Art Dickenson, who have turned their Jags into absolute beasts. Contact Bradley Smith as well. He has a supercharged V-12 XJS that is an absolute monster.

But before you get started with all of this, ask yourself how much money, time and effort you are willing to put into this. You are not just going to bolt on a supercharger and turn your car into a snarling 700 HP dragster. Ask Art or Bradley how much is involved. In time, effort AND money. Then, do a few of the things that Wayne and The Book suggest, and go enjoy your car. My $.02.

Steve Weinstein
'72 E-type 2+2
'70 XKE FHC
Former '89 XJS Coupe owner

12 years experience in JCNA Slalom Competition, my quest, fairness in competition for all members.

Hi, hope you like your new car, I have owned an S for 14 years now, it started off being a weekend/sunny to work driver. The car is now a railer riding slalom car, currently the fastest S in JCNA Slalom Competition, and has been for 12 years in a row.
If you have not seen the video on my car send me your E Mail and I will send you a copy, and tips on how to make your car get up and go MUCH quicker, Art , My E Mail is silver007shaw.ca