I am at a crossroads. I am wanting to get rid of good intentions and settle down to just a couple of my favorite cars. I have over the years purchased more than I will ever get around to. I have in my possession a 1994 European XJR6 with a Gtrag 5 speed. I also have a 1988 XJS SC that is a pretty decent car that is a original 90k mile car that has never been molested in any way. I also have a 89 convertible that I had intended on converting to a 5 speed. Unfortunately, it dropped a valve seat, and now has been sitting at least 5 years on Dolly's in my garage. Because the XJS SC is a combination of coupe and convertible, it seems that it would be the better car to build a XJS with a XJR6. Can anyone on here give me a realistic idea of what I am facing in converting either of these to a XJR6? I also have a very nice triple black 95 convertible but hate to change it from it's original condition. The other two cars, not so much. Oh, and one more thing, I have a strange desire of doing another MGB v8 but this time a GT. All thoughts appreciated as I go through my 4th or fifth now late life crisis. Growing older seems mandatory but growing up is completely optional.

 

superchargedtr6 (I Sooo want to do that to my TR6!),

I know you don't want to hear this but your 95 convertible is the one to convert for so many reasons!

An AJ16 manual supercharged XJS is the car Jaguar should have built in 1995. Your 95 car already has so many components and wiring relevant to the XJR6 that its the easiest and most appropriate one to convert. You absolutely wouldn't regret it and you'd have the ultimate 4 litre XJS!

Go for it!

Paul

 

Converting an XJS to XJR power is not that bad and will be far easier since you have a complete car. I've done 2 and recently sold one on Cars and Bids. You will need a few specific XJS 4.0 parts like a radiator, mounts and A/C bits. It's basically a bolt in except for the transmission mount. You may need to make that.

That said the XJR engine is great with a 5 speed, I've got a project in it's final stages so I'd know. Much more spry than the auto version. BUT.... NOTHING compares to a 6.0L V12 with a manual.. Nothing. If done well with a fresh slick shifting gear box like a NEW TKX or T56 then it's the most fantastic driving experience there is. I'd never recommend going through the while process and using a old crunchy gearbox like a Getrag.

You have to figure out what YOU really want or have to have. Any project like this will be difficult, time consuming and expensive to do right. For example, my desire is a XJ6 Coupe with a 6.0 V12 and T56 Magnum with a stiffened chassis and taught suspension. Even though I've got a V12 convertible, I think they are better as cruisers because the chassis is jiggly and in my usage case that wont be right when setup as a performance facing manual conversion. I'm sure of this and if you don't know just wait until you know.

 

I may should have mentioned in this that I also have a 71 XKE V12 that I have converted to the Z series tremec 5 speed. I have done everything I know to do from large torsion bars, all aluminum cooling components, aluminum coil overs, ss headers, yada yada. It is a blast, but definitely not a daily driver. I'm wanting a car that I can drive most every day. I don't really have a definite decision to not convert the 95, it's just that I don't enjoy driving it. It is a lazy feeling car. Not just in power, but the way it feels in the curves.
I am a member of a active British car club and enjoy the drives through the scenic Carolina mountains. I don't enjoy the guys with the smaller cars being able to take the curves with ease while my E type tires squeal as we take curves at 40-45 miles per hour. That V12 loves to go straight. I didn't know if the XJS SC might feel a little more "sporting" while taking the curves

 

A well sorted XJS coupé will outcorner any E type. The XJS convertible is a very floppy chassis, and in my opinion would be a poor choice for more power, especialy if handling is your priority. The XJS Cabriolet is nearly as rigid as the coupé and would be good choice for your swap.
The key thing with the swap is to ensure all the required looms, coils, sensors and ECUs etc etc needed to run the supercharged engine are carefully noted, understood and kept for reinstallation. I have a feeling that even some of the items like ignition switches might be recognised by the ECU and the engine will not start if they do not identify themselves correctly - though this might only true be on later cars X308 generation cars. Worth testing it all for this sort of thing before you tear the donor part though.

 

The fellow I purchased the engine from supposedly built it for a xjc conversion. Then went Aston Martin V12. This engine and transmission came with the aftermarket efi and all the gauges. If I remember correctly, he even had the engine dyno'd at 410 hp. It is absolutely beautiful sitting there on the crate. I didn't realize that the GTrag was clunky. I've never driven a car with one. This is a Gtrag 245 I think. It supposedly is all factory. I lean toward the XJS SC mostly because it is a convertible and a coupe. I just turned 62 and we all know the XJS is a comfortable car. I have always loved having a convertible, yet as I age, having a car that will cool down inside is nice too. Not to mention enough trunk space to carry two or three days of luggage and being able to secure it. Whenever we go on a trip overnight in the E, I almost can't sleep for thinking about how easy it would be to steal. I've had it a very long time and probably have more than twice what it's worth in it, but it is a beautiful ride. I went recently to the BritishV8 meet and was able to ride in several MGB GTs. One of which is this car https://www.hemmings.com/stories/202...ful-sports-car
Zach and his wife have put over 7500 miles on this car, and the most telling thing was his wife talking so enthusiastic about their travels in it. Zach encouraged me to follow through with converting the XJS SC with the XJR6 mostly because I have them. Sometimes fate and reality have a way of dictating direction. None of my cars have a any rust. That's a big plus to me as it save a a lot of time and money on a restoration. So far, all the MGB GTs are questionable as far as rust goes. When Zach and I rode in the GT, we both are big fellows and we all know how it is riding shoulder to shoulder in our LBCs.
I'm still enjoying your responses. Thank you

 

More advice, even though you didn't ask. Skip the XJS SC. It's only marginally more rigid than a convertible. If you're going for a comfortable performance GT then start with a coupe. The solid roof and rear buttresses on the coupe make a tremendous difference. I think I know the gent (Rusty) you purchased the engine from, I sold him the AM V12.

 

I bought the XJS SC not running. I have never driven one. I own and have owned several XJS'S and none have ever impressed me as a sports car. I'll take any advice even if not asked for. To be honest, I really don't know what I want. 5 years ago, I had all kinds of good intentions but life has a way of changing. Now? I guess I am much like all of us looking for that balance. I've even toyed with the idea of completely clearing the deck (including my E) and try and find that toy/driver that I can enjoy/drive/enjoy more on a daily basis. Any comments appreciated

 

Some of the manual cars had the Sportspack suspension, ie rear anti-roll bar, stiffer springs and shocks. Firms up the ride and flattens cornering quite effectively. And plenty of XJ-S coupes are raced, so handling changes are possible.

 

The key to XJS handling, in my opinion, is reducing weight in front of the front axle, plus camber adjustments. When I removed the OEM hot-country thicker radiator and replaced it with an aluminium I noticed a difference to the turn-in on corners; I calculated that I saved about 20 kg (water and radiator together) from a location 10 inches forward of the axle line. If you can do away with the aircon (impossible if you are in a hot location) that makes a very noticeable difference.
However what made a HUGE difference to the turn-in was a negative camber increase, allied to with an inch or more drop in front ride-height. Now this eats tyres, and you have to look out for humps etc, as I found out, but if you are brave enough, about 1.5 degrees negative (OEM spec 0 to 0.5 degrees) absolutely transforms to cornering of the car. But watch out for tyre wear!