i have added or increased size on a few cars, frt&rear, found the ride goes to h#ll!
not the famous Jaguar ride!

 

 

Me too !

Jaguar, like all manufacturers, faced many decisions and compromises when building a car. When facing those tough "more performance?" or "more comfort?" compromises Jaguar always went with more comfort.

That's not a criticism, mind you. Not at all. But, it leaves us with cars giving a bit more body roll than many like, soft bushings that wear out sooner than many others, exhaust systems with zero tone, and so forth.

As for suspension, for decades, and perhaps still, Jaguar was famous for great handling and a comfortable ride. It must've rankled the competition that Jaguar managed this so well. But, still, it was a compromise. In my experience and opinion a few minor mods yield large improvements with minimal negative side effects. As for anti-roll bars specifically, well, Jaguar itself used larger bars and/or rear bars on many XJSs....so any of us duplicating Jaguar's own work seems perfectly reasonable to me.

Cheers
DD

 

LOL... they went bankrupt this way.


So its the early 80s and Jaguar is no longer fitting rear sway bars, their cars are getting heavy and they are not selling manual gear boxes. BMW on the other hand is designing and building the E32 with both a 6 cyl and V12, both have rear sway bars and a manual transmission is available on the 6 cylinder short wheel base version. The rest is history.

BMW looked at the demographics, Boomer's were in there late 30s and 40's and created sports cars with the edges smoothed over so they were less offensive, Jag made the wrong call, They had no real etype replacement and ignored the demographics. By 1990 they were headed to bankruptcy based on just 2 poorly selling and dated products. Porsche was in the same position.

 

If you look at Jaguar advertising...particularly XJS advertising for the USA market.... from the 70s thru the 90s a very clear pattern emerges. Performance is gradually de-emphasized; fewer and fewer references to power, acceleration, sportiness, racing heritage, and so forth. More emphasis on comfort, luxury, elegance. Unwilling to make the XJS competitive they turned it into a 'personal luxury car' for the country club crowd.

Things began to turn around a bit with the supercharged XJR in 1995 and the XKR in 1997. But, still, the country club reputation lingered on...while BWM and Audi scooped up buyers wanting something more performance-oriented.

Still, in the days when Jaguar was a player, the suspension was considered a strong point: comfortable and good handling...with comfortable taking a front seat.

Manual transmission? Well, the market for Jags with manual transmissions has never really been there. From 1975 to 1980 only about 350 XJSs were sold with the manual shift. In the 80s and again in the 90s the 6 cylinder XJS was offered with a manual trans....but there were never enough 'takers' to make it worthwhile keeping it on the option list. And, in the present day, Jaguar is once again taking manual transmissions off the option list- too few buyers.

Cheers
DD

 

I love Jags, but they really did hang on to the past for far too long. It's really only since the new breed XF, XJ and F-Type that Jag shook off old styling connection and the company has really moved forward. Ultimately Jag were dragged into financial strife due the unions, politics etc of the UK in the late 70s and didn't really recover for a LONG time.

We digress! From a purely suspension/handling point of view, the ability to tune the front and rear roll stiffness is massive. I'm going to attempt to to make my rear bar adjustable via lever arm length (probable three different positions). I should point out that my car will also be running a set of Australian made King Springs that will help the car sit a little lower. The spring rates are raised slightly and in doing so add some additional roll stiffness in their own right. I know that the std rear spring are around 200lb/in and the 'lowered' King Springs are 260 lb/in. I have decided to run 250lb/in at the rear, knowing that i'll be running the rear bar. Time will tell if I've made the right decision. The car also runs the Gaz adjustable dampers, the rears run adjustable spring platforms too (hence the ability to run different spring rates easily).

 

seein you guys are interested in performance driving , a few mods i made,20 odd yrs ago, the 1" frt bar made a huge difference , but i could feel some FLEX in the engine compartment area!

so added this 1.125" tube across the bay, then added some solid aluminum bushes to a steer rack , you talk about good steer response , BIG improvement!
i have HD shocks all around, which can/will aggravate handling, along with heavy frt bar!

my tires get serious grip ,car needed it ,275/35/18. all around.
lets not forget my XJS is an open roadster so flex between the frt & rear is very noticeable , but it is what it is, i live with it no problem, you just drive into it and get it done \>LOL.LOL.

a good mod would to make some ALLY bushes fro the front subframe, that thing squishes and wiggles all over the place, rear sub also, ally mounts!

HEY if you gonna do it ,DO IT RIGHT , any thing halfassed will be just that!

OK i been ranting ,
ron