I think the rear wing on the XJR-S develops some vacuum that sucks money out of buyers’ wallets.
Maybe the angle of attack of the airfoil is held at the optimum angle to minimize turbulence and provide lift (downward force here because of the airfoil shape orientation) at higher speeds where loss of traction likely to occur?
If you look at the DRS (Drag Reduction System) used on F1 cars, it works entirely by changing the angle of attack. In slow sections of the track the flap is tilted up for maximum downforce, on the straights the flap is flattened to reduce drag.
Yes. True. But the airfoil on the XJS is not moveable …
But for a few dollars more…
The design engineers did such a phenomenal job with the face lift touch ups to the XJS… and then you add that rear spoiler and you have a car (preferable convertible) that truly attracts attention like few other cars can. If you ever have a chance to drive a face lift convertible with the top down AND that classy rear spoiler in a rather busy street . . . . you’ll know exactly what I’m talking about…
And, is utilized at much higher speeds, and intensively designed and integrated into the air stream of the car.
Cool looking, on streeters, but essentially non-functional.
Like the wings on Superbirds…
From a Motorsports article in 1975;
Throughout development Sayer’s “slippery” aerodynamic design was harnessed, as he intended it to be, to contribute to road-holding and stability. As an adjunct to his basic design, Jaguar engineers added a spoiler and an undershield resulting in the MIRA wind-tunnels in a 50% reduction in the tendency of the car to lift and 10% less drag. The spoiler also reduced aerodynamic side forces and moved the centre of pressure rearwards as an aid to stability.
At what speeds? That’s a critical question.
Unfortunately not expressed in the article.
I suspect it’s talking about the front spoiler and undertray, though. And yeah, a front spoiler can have a significant effect at normal street speeds.
This indicates to me they are talking about the rear spoiler?
As for the antenna being up when the CD operates, this is for a very good reason in Europe/ RoW if perhaps not in USA. Namely, RDS (Radio Data System) and EON (Enhanced Other Networks).
Default, if you have the head unit set correctly, is that you will receive traffic alerts related to the area you’re driving through. This was years before GPS became commonplace and it used radio reception areas as the guide for which bulletins were local and therefore relevant. It also kept national FM stations tuned to the strongest signal while driving through various frequency areas, ready for when your CD ran out or you went back to radio listening.
To work as designed, RDS and EON required the radio to receive and monitor a signal at all times, hence aerial up even if using only CD.
As with many aspects of Jags and others, it’s one of those things people say is stupid. Not because it’s true, merely because they don’t have all the info or haven’t figured out.
I don’t care for the spoiler on the facelift cars. It takes the car firmly into the early 90’s. Without it, even a late facelift XJS passes for a early 80’s car, which is the character and ethos I like my car to have. TBH, lately I have even been thinking that most of the 16 inch wheels they used towards the end are really unbecoming to the cars design. My car has the 5 spoke wheels, but I would prefer the 16 inch lattice or the “platter” type wheels that were an available option…Lots of manufacturers kind of “tart” up their cars towards the end of production, I guess.
Yep. It is the front chin spoiler. According to Skilleters book” it reduced front end lift by 40% and moved the centre of pressure back improving stability. It also improved the drag factor by 6% and helped cooling…”
Totally agree on that.