I just want to clarify some basic concepts of “Chevy conversion 101”
Jaguar cars became well recognized here in So Cal during the series II and III XJ6/12 and the birth of the XJS in 1975. The body style was glorious for the time, making the sedans a true sculpture of a car compared to Detroit’s square bricks. But, what did become well known, as well, was how immensely unreliable these cars were, particularly whatever came with the V12 engine. It was like Ms. Universe with VD… I have found that many V12 owners in forums tend to ignore this V12 fact and reality. I know of California, but why would it be any different in other places? If there was one thing that everybody came to learn about Jaguars was to stay clear from the V12 engines because of the widely known disastrous reliability that, clearly, was far from emulating some other prestigious V12 cars. I always remember this Euro/import car show that no longer exists (many Ferrari’s, Lambo’s, Maserati’s, etc.) where this 80’s XJS was being shown with the hood open and a bunch of people surrounding it… The blunt comments went from how these V12’s couldn’t be kept running, or died on fires, to how hard and/or super expensive it was to fix them, as they looked at the super busy engine bay in front of them. This typified the overall Jaguar V12 awareness in those years.

So, what would one do with such an admired body style, but with a cancerous engine? Save the beauty’s life and cut off/ditch the cancer away. Thus, many Jag Conversions places were born and kept busy for quite a few years, with plenty of weeping clients in search for answers. This is the way, the concept, under which the Jaguar-Chevy V8 conversions were born. It was not about being cheap or bad taste, but about practicality and those people’s wallets. Those who do not agree don’t know this dark side of the V12 history. Today, not many conversions are performed because Jaguar’s reliability has gone up by leaps and bounds, as even power-wise Jaguar has come up with the match in the form of V8’s, superchargers, or 5.0L engines.

Without being a power house, the AJ16 engine is very reliable and smooth. Unless its engine died in some weird and absolute catastrophe, the XJS/AJ16 (’95-’96) combo is perfect and it should be left alone. The whole car is reliable, very reliable if compared to Jaguars of the ‘70’s and ‘80’s.

If a coupe or convertible Jaguar with more power is desired, then get an XKR and do a couple of mild mods and you get a 400 HP Jag.

But if one was to insist in a more powerful engine, but staying with the XJS, then do what that Kiwi company does: Stay Jag and put a S/C AV8 Jag engine on it.

IOW, today is no longer justified to put a Chevy engine in a Jaguar. If you insist in a Chevy engine, buy a Chevy car.

Cheers,

 

Why would you spend so much money on the car then not fix the roof motor and trunk cable ???

 

You guys make a lot of sense ...thank you for the great comments
i just received photos sent to me by the seller of that 96 with a LT1 engine . I will upload them later....
Its true that 22k is a expensive for that car. I m suspecting that's how much money was invested in it and the seller whats to get it back.
But that does to always work that way.....the market dictate the price not the seller ...

 

That's exactly why I drive a 6. Jaguar was my first favourite make (when I was 10) and has been all this time (I'm 47). All sixes. Add to Allan's list all those fantastic saloons (Mk2 !!) and the D-Types that won LeMans. So to me the most appealing Jags have an inline 6.

Unfortunately, virtually all XJ-S V12s are handicapped by their three-speed automatic. Blah. IMHO the V12 auto belongs in the XJ12 where it is sublime. Emphasis on smoothness, not quarter-mile dash. Also, the XJS 4.0 with 5-speed manual is a BLAST to drive, and it sounds right.

As for XJS-Chevy? That's not gonna be bought by someone scoping car ads for a Jaguar. Jaguar guys aren't the target market. You'd have to park it somewhere visible and let it's natural beauty bring potential buyers forward.

 

Let alone that 2.88 rear end...

 

Posted twice

 

Just want to make sure I didn't offend anyone with my V12 comments above. To be clear, when anyone buys a car they like, they are not wrong. My opinion about your car ain't that important. I do enjoy driving a V12 XJS automatic, but since I could only own one Jag, my first choice was the 6.

 

an observation i'v made over the past 20yrs, Jaguar 6 cylinder VS Jaguar V12 , it seems the guys who go for the V12 have a higher Testosterone level!!

more willing to go for the bragging rights and deeper subject of a BIG V12 than a bittsy 6 cylinder lower level engine!

no matter how they drive or run. just something about it, thats almost magic!

 

Ronbros,
Not sure what you mean when you say " the guys that go for the V12 have a higher testosterone level ". When did we start comparing someones level of testosterone to the engine they have in their car?

I would say a more accurate statement for you would be; " I am so loaded up with high levels of testosterone that instead of buying a series one E-type or a later model XJS with that bittsy 6 cylinder lower level engine , I had to settle on a 1978 XJS coupe and then cut the roof off to make me feel like I have something special ". Wow, how can the rest of us with our little bittsy 6 cylinders get those abundantly high levels of testosterone so we can make those brilliant choices?

With my apparent normal levels of testosterone I thought I was reading a insightful post on what the value of a converted XJS is worth, and why people in the first place started to convert the V-12 XJS to a Chevy V-8, but hey I am heading down to GNC as we speak so I can start pumping my body full of testosterone filled supplements so I can see the light and go find a older XJS coupe and start cutting the roof off. The up side to this will be with all my new found testosterone I will be able to rip the roof off with my bare hands because I will have so much more energy and raw strength!!!!!

 

Well i am assuming that this testosterone is measured by the presumed power of the Jaguar V12 engine, only thing is that several minivans and supercharged 4 cylinder cars could leave our V12's in the dust any day of the week.

I own all of the Jaguars in my signature line and I can tell you that all 3 have about the same power. The V12E type is by no means capable of beating the XJS or X type in a street show down. Even when it was in production these cars where no Ferraris in terms of speed.

 

I love my v-12s. Nothing like it.

The car I wanted was a 6.0 Benz SL v12 which is out of my price range. These cars are 145k new and still expensive used, My hanger queen low mileage v12 cars always get a few lookers at any car show.

If not for just the curious but the fact that these are fairly reliable v12s with very little maintenance and a good preventive maintenance program. They can't seem to believe that my cars don't overhead in the 120 degree summer heat here! The AC even works too.

 

NO its not about the power or smoothness of the V12 , its the type of people who take on the(so called) CHALLENGE of a V12, they got bigger plans and aspirations!

just want to feel and think ahead of the satus quo!

ck out my garage , Mazda RX7 500hp out of 1.3L engine.

i'm bettin they have a higher test levels!

 

I don't think the average XJS owner gives a rat's patoot about what he can beat on the street, nor do I think that is why he bought an XJS.

The "Honda with a Fart Can" mentality usually does not buy Jaguars, for whatever reason.

 

Too true. The overwhelming majority I see (fewer and fewer as the years go by) are driven as though they are made out of glass. I've driven a few that were performing wayyyyy below normal and the owners had no idea at all that anything was wrong.

To each his own, of course, but the XJS is actually pretty darn capable when driven hard and fast.....a certainly not fragile.



True again ! But, let's not suggest that someone who IS interested is increasing performance, or who drives their Jag hard, is necessarily the Honda-with-a-fart-can type

Cheers
DD

 

Doug,

Too true as I happily found out this weekend at a JCNA slalom. What a hoot it was to fling the old girl around the cones. I think she acquitted herself quite well. Although big and heavy the XJS has great roadholding and handling abilities.

Cheers,

Allan

 

We had a British car show at Liberty Park in SLC, UT. The MGs and TRs went first, then the big '92 XJS with original Pirelli's sliding sideways through the course.

It will take a lot of work to make a Chevy or transplant engine car handle like a Jag!

 

The vehicle dynamics are going to be totally different unless you put a 700 to 750 lb. engine in there, plus headers, manifolds and so on. Of course, you can completely re-do the suspension to offset the change in weight distribution, or ballast it.

I just think it is a bad idea all around.

 

As far as I know the popular conversion kit vendors sell front springs to to compensate for the lighter small block Chevy engine....so that's no big deal at all.

By all rights the car should corner better with a bit less weight up front. Less understeer.

Cheers
DD

 

Yes, Doug, I know that most of the local conversions places in this area added a spacer to the front springs. When not done so, it's quite easy to spot the conversion cars, as the lighter engine weight would leave a gap between the top of the tire and the fender well lip that doesn't exist with the V12 in there.

Cheers

 

I'm really enjoying this thread, guys :-). Jaguars, especially the E-types and the XJS convertibles, were one of the few marques I could ever recognize, and the only one I ever truly wanted to own (well, except for a Rolls Silver Shadow, but I wasn't keen on the chauffeur who'd need to go with it). And, yes, I wanted the V12 XJS. Only thing is, although psych tests tend to say I'm kinda masculine in thinking, I'm actually female, so the "hyper testosterone" theory doesn't work so well.

Now, about those rear windows being up -- ummm, isn't that their normal position? Because that's how mine are, and I'm pretty sure I'll reach retirement age before I can find a &*(^% window motor to get the right one to work again :-).

- Gina