Assuming both cars have the 370 hp SCed engine, and aside from the length of the cars and the cosmetic differences, what is mechanically different between the two?

 

The Vanden Plas S/C (only) has the same engine but it has a different suspension and wheels. The VDP has the adaptive controlled comfort suspension and no rear anti-roll bar. The wheels are 17" with 235/50/17 tires. The car has too much body roll when cornering and I am trying to find a rear anti-roll to install onto my car
Does anyone have a rear bar for sale?

Ed
2001 VDP S/C BRG

 

Have you driven a non S/C VDP before? If so, how does it handle/ride compared to the CATS VDP S/C? I have never driven a VDP S/C.

Have you changed the sway bar bushings? The dramatically reduced body roll in my VDP. The VDP seats don't have enough lateral support though. I gotta make sure the passenger window is closed and I'm buckled up or I could fly out of the car on a fast turn! Haha.

 

The VDP is a LONG WHEELBASE CAR.

bob gauff

 

Burmaz - I only drove a non S/C VDP a couple of miles that was on a dealers lot and I did not push it. I have changed all of the bushings (sway bar, control arms, shocks), balljoints, tie-rod ends for the front suspension. The suspension is tight without any squeaks or thumps and tracks straight. The car finally rides great but it rolls to much for my tastes. I am willing to give up some ride quality for less roll. I tried replacing all 4 shocks with the standard Bilstein Sport XJR shocks and the ride was terrible and it still rolled too much. I put the adaptive shocks back on using all new bushings

 

Rolling can generally be solved with stiffer springs, swaybars, and strut bars. Assuming that you don't want the stiffer springs, look into either finding or having a strut bar custom made.

There can be some research that goes into maximizing the design of the strut bars, but all they really do is keep the tops of your strut towers from flexing, so even a simple steel bar will improve your handling.

Sway bars link the bottoms of front/back shocks together, in pairs. This causes the shock under the most stress to send some of that pressure to the shock opposite it, which is usually under a different degree of stress. These can also be made by hand, but there's more work involved with these. There are also varying degrees of quality.

Finally, lowering the center of gravity assists in the rolling of the car. This is not only because of mass physics, but also because the shocks you use to lower the car, and the springs as well, generally are stiffer.

 

Also, let's be realistic. It's a heavy car. It'll never not roll. The most one can hope for is less roll.

 

The XJ8/R do not have struts but rather the "proper" lower and upper control arms.

Shocks have nothing to do with sway or anti-roll bar.
The bar work in the following way:

When you go into a turn , the front suspension member of the outside of the turn gets pushed upward. The arm of the sway bar gets pushed upward, and this applies torsion to the rod. The torsion them moves the arm at the other end of the rod, and this causes the suspension on the other side of the car to compress as well. The car's body tends to stay flat in the turn.

 

I'm not really sure why I said shocks. I was posting at the end of being awake for 38 hours. Maybe that's it. Yes, that's it - sleepiness, not ignorance. Hah.

Luc's right. Regardless, the principle remains the same. Compression on one side causes lessor compression on the opposite side. It's also fair to note that sway bars can vary in thickness, and create various results. Road racers balance their sway bars to create the best dynamic for their cars.

How sway bars work

I didn't know that the car didn't have struts. That said, it still has shock towers. Strut bars are used to brace those towers in cars with struts. Is there no equivalent use for such a bar in a XJR? Wouldn't it at least brace the chassis? A braced chassis improves handling, regardless.

 

You could probably fit almost all XJR suspension to a VDP S/C, but why bother, They're at both ends of the XJ spectrum, one is for chauffeurs, the other for drivers ;-)

 

From a family hauling perspective, the VP is superior. I have a family. The XJR will do the job just fine, but the extra room in the Plas is a ... plus. Plas plus.

 

I wonder why jaguar never fitted a rear antiroll bar on the or XJ8. I doubt it would really negatively impact the ride all that much.

I do wonder how adding a XJR rear sway bar would affect a long wheel base XJ. The LWB is tuned to plow and understeer . I wonder if it would neutralize this or make the rear end unstable and prone to excessive oversteer.

Have you driven a XJR? If so, how does the ride compare to the CATS VDP S/C? Btw the .80G for later accel that the XJ8L standard VDP gets is poor. All understeer.