New xjs owner and member

If you want to shave pounds then go for fibreglass. some shops will make a mold off your current pannels, then you can just about bolt them on. Its not cheap but is cheaper than running twin turbos into a super (with 40-50 pounds of boost) and is not as rediculos. Another option for performance is to go to a head specialist and kindly ask them to make a set of performance heads. or buy a new jag v8 they perform like a lotus and weigh 2-3 times as much :)

I have heard that a jag v12 can be bored out to (up to) 9.1L but this was maximum, they can safely be done to about 8L, but remember the fuel. Before anyone says this is bs, have a look at a v12 with the heads off and look at the amount of space for cooling. I believe that this space was also ment to reduce noise.

>>Jaguar Jeff said...
If there was only a way to trim Five, Six hundred pounds off these cats we would not have to be concerned about engine mods.......

A friend of mine recently restored a ser1.5 E-type. He was driving it around without the bonnet for a few weeks. Believe me, with that "slight modification", the car was a screamer!

John Testrake
Jaguar Association of Greater St. Louis

If there was only a way to trim Five, Six hundred pounds off these cats we would not have to be concerned about engine mods.......

Jaguar Jeff
'95 XJS 6.0L Conv.

Hi Shihan,
Other items to consider are removal and substitution or the resonator just before the tail pipes, just a piece of straight pipe will do, this will increase the DB rating to a more powerfull note, and give you a few horse power to boot. The stock wheels can be replaced with aftermarket mags, the bolt pattern is CHEVVY so choice is immense, choose a lower profile tyre and this will also give you more gearing till you get the rear end changed to a 3.01, or as mine a 3.54. Your stock engine computer can be uprated by AJ6 Engineering in England. ANOTHER ITEM is the stock torque converter, this beast is 13 inches in diameter, and takes quite a bit to spin this baby. Ther is several companies who sell uprated furnace brazed converters in smaller diameters that will allow the motor to spin up quicker, mine sure does this year, could be hard on tyres though, still tyres are relatively cheap, if you want to go fast be prepared to fill up the gas tank sooner, rather than later.
Finally if you want to have some fun with your car attend one of the many JCNA Slalom's, these are relatively low speed events , but no tickets are never handed out for squealing your tyres. I have been doing this for 12 years now, and what started out as a Sunday driver, was last year the fastest Jaguar in all North American Comp. This 1983 XJS Coupe has beaten up on Ferrari's, BMW's, Corvettes, you name it we have probably blown it's door's off. Currently the car is awaiting suspension components worthy of an F1 car, but locally made for a great buck for a great cause.
Need more info, just ask, Art, Grassroots Racer.

Stevo,

You're certainly right that the modifications that he was talking about are not cheap and not readily available, like souping up a Chevy or a Mustang. But others have done it and it is available, if he's willing to spend the money. I agree that someone who buys an '84 or 85 with 200K+ miles is not likely to want to spend that kind of money. But why not at least point him in the direction of some meaningful information so he can make that decision for himself?

Art put out several relatively easy, not terribly expensive modifications that will make any XJS much quicker. The list goes on and on, and suggestions like Art's at least point the guy in a direction. But simply yelling at the guy adds nothing and leaves him feeling that we in the Jaguar community are unhelpful, or worse, downright nasty. I, for one, don't want that to be the way people view us. I'd much rather lend a hand whenever possible.

BTW, I know Bradley Smith and Brian Maletsky of Motorcraft, Ltd. who did most of the work on Brad's car pretty well. I personally observed much of the progress on the car at Brian's shop. Yes, it was a bear of a project and took years to do. But now that they've done it and have sourcing on materials and equipment, the next one won't be as major a project. Not cheap, I'm sure, but beauty is in the eye of the beholder and I learned a long time ago not to look into other people's wallets.

Steve Weinstein, JTC-NJ
JCNA Slalom Committee Chairman
JTC Slalom Chair
'72 E-type 2+2
'70 XKE FHC

Hi, if you check out the slalom page you will see that an XJS owned by Art Dickenson is quite quick.Here is my tip to you to make your car very quick, but bear in mind it will use more gas as a direct result.
1. instal 3.54 gears to the rear end
2. instal K & N filters.
3. open up air filter pipes, or just cut them off at the filter end of the housing.
4. instal a shift kit in the T400 Tranny.
If in doubt check out the video clip of Silver on JCNA Web page,
Good Luck, Art Dickenson.

Sorry you thought my comments were "rude". I guess telling a newbie that his dreams are not realistic for a V12 Jaguar is somehow insulting. The facts are that Shihan was asking about MAJOR mods, not simple performance upgrades that are available from purveyors like AJ6 Engineering in the UK. If someone is dreaming about stuff like that, he/she better stick with 350 Chevies or Japanese tuner cars, for which stuff is READILY available at something approaching affordability. Bradley's supercharged V12 is not a good example of a modification that a person could practically duplicate. First, it cost megabucks (more than $50K) and took a LONG time (years). There are no KITS you can buy to turbocharge or supercharge a V12, and the engine already has VERY high compression (more than any other production car).

So my point to Shihan is very GOOD advice...there is no way within any PRACTICAL reason to install the mods that he was asking about in his post. Surely it is obvious that anyone who buys an 84 XJS cannot afford the mega bucks it would take to make the type of mods Shihan is dreaming about. So forget about that stuff. I NEVER said that an XJS wasn't any fun or a good performer...just that it absolutely doesn't lend itself to the kinds of mods Shihan was asking about. Prove me wrong...tell me of some kind of KIT you can buy.

Stevo

Wayne's article is right here on the site click below.

getting significant increase in power on an XJS isn't cheap because there are fewer upgrades available than from your basic Chevy V8... it's not like you can go thru a catalogue and get a bunch of parts.

On the other hand the V12 is one of the best engine ever built, winner at Le Mans and still raced in europe in a Lister...

Pascal Gademer
South Florida Jaguar Club
72 E-type 2+2
00 XKR Coupe
99 XJR

Sorry that Stevo's comments were so unhelpful and downright rude.

I owned an '89 XJS Coupe for several years. Just sold it this past spring to buy a second E-type. There are many things you can do to improve the car and maximize performance. Despite Stevo's negative attitude, from my experience, driving an XJS can be fun, exciting and even thrilling. My car was relatively stock, but I had a great time driving it on the track at Lime Rock two years ago.

First and foremost, you MUST go to www.jag-lovers.org and download "The Book" by Kirby Palm. Follow the links on that website to the XJS-lovers page and you'll find links there for The Book. It's a compilation of the experience of hundreds of XJS owners. You'll find a wealth of information there.

The next thing you should do is sign up for the XJS mailing list on Jag-lovers. Also, browse the archieves there for multiple threads that have gone on about supercharging the XJS. There are several "listers" there who have done major modifications to their cars, including Charlie Mariah and Bradley Smith. Bradley's car is supercharged and was written up in Jaguar World Monthly last year. I've seen the car many times, and it is awesome. I believe it dyno'ed at over 650 bhp. Charlie has souped up his XJS and turned it into quite a race car. It can be seen at many of the tracks in the Northeast these days.

Also, a guy named Wayne Estrada has written many articles with suggestions on how to get more performance out of an XJS V-12. Try Google searching "Wayne Estrada Jaguar XJS" (or XJ-S -- the hyphen was in the name until the early 90's, I believe), and you should find his website. You many also find some references or links to Wayne's website or his articles over at Jag-lovers.

Hope that helps, and do let us know how things go with your projects. Remember though -- the one thing Stevo said that is true is that a lot of these modifications are not cheap. But if you like the car, want to improve its performance, and its what YOU want to do, go for it.

Steve Weinstein, JTC-NJ
JCNA Slalom Committee Chairman
JTC Slalom Chair
'72 E-type 2+2
'70 XKE FHC

Shihan wrote:

"I bought the 5.3 V12 and am hoping to get some real performance out of this engine.I am considering it all Twin turbo's,superchargers or just simply higher compression.Sigh...........Am I in for a real headake or what should I take up stock in asprin as I enbark on this adventure?I certainly cant be the first to want to do this....Any advice guys? "

Yeah...FORGET ABOUT IT!

Twin turbos: You can't afford it.

Superchargers: You can't afford it.

Higher compression: Are you kidding!

Stevo