1991-1992 Jaguar XJR-14

Images copyright Bob Jackson, Paul Ajari, & Michael J. Fuller
Text copyright Michael J. Fuller

Jaguar XJR-14The XJR-14's front end aero is dominated by the front wing.  While not historically unique (see March, GRID S1, various Porsche 956/962s) , the XJR-14 seemed to revive an interest (if briefly) in the concept with the rival Peugeot 905 taking cue.  Front balance could be adjusted through changes in flap angle, in addition to the louver panels.
Jaguar XJR-14, Del Mar 1992A variety of large trailing edge extensions for the front wing flap were used during the XJR-14's IMSA GTP service.  Del Mar here:
Jaguar XJR-14, Portland 1992Dive planes were also raced (used at Portland, here, Miami, etc., though first utilized at 1991 Group C events such as Magny Cours), this, in combination with the larger and larger front wing trailing edge extentions, in an effort to balance the car as total downforce was increased at the higher downforce US tracks.
Yes, that's a Bentley LMGTP in the background...The front wing was developed as a way to produce the required amount of front downforce within a shortened front overhang dimension.  Says Mark Thomas, the Jaguar XJR-14's aerodynamicist, "With the way the regulations were, with the wheelbase and overhangs, we were looking to get as much of the overhang to the rear as we could."  This was out of the desire to accommodate the twin-tier rear wing and to further maximize the downforce produced by the underfloor.
Jaguar XJR-14Mark Thomas was adamant that the flow spilling off the trailing edge of the front wing flap didn’t have a detrimental effect on the rear wing.  Given the proximity of the bodywork to the trailing edge of the flap one could think that the airflow had time to regroup before heading to the rear of the car therefore was possibly less detrimental.  But according to Thomas, a better solution was on the drawing board, one that utilized a front diffuser arrangement, but time had run out and the aero group had to go with what they had.
Jaguar XJR-14The XJR-14's radiators were midship for weight distribution priorities and with rather simple and uncomplicated inlets.  Once through the radiator, the air then exited the car through the engine bay and out the rear of the car above the trailing edge of the underfloor.

ęCopyright 2009, Michael J. Fuller