I believe it. My coolant temp always goes down when the airflow is really high, like 80+ mph.

Z

 

I dont think it is written anywhere but I remember all of it. To save cost, XK8/R systems were validated using Ford test sites. I was a young engineer and not a cog in the process but witnessed the whole thing unfold.

The Thermal Load for X308 XJR had already passed test on the Calorimeter. This is where the cooling pack (Engine Rad + AC Condenser + Intercooler Rad + Oil Cooler) was tested for Duty heat rejection. A wood panel with sized grill opening was placed in front of the pack and specific performance measured. Notably, the X308 XJR had a much larger grill area (due to the under bumper opening) so received more forced ventilation.

Later, the X100 XKR pack was tested but grill was half the size and failed multiple times. A test fail was low heat rejection performance so less efficient. In XKR case, that would mean overheat risk for engine and inefficient intercooler, transmission and AC. Slightly smaller condenser was tried (X100 cabin volume was smaller than X308) but no good. The wooden choke panel with grill opening was then increased until test pass. Engineering requested an increased opening of 20,000 mm2 to compensate for the auxiliary radiator.

Superchargers create a lot of heat and at the time, Supercharger variants were starting to appear on mainstream vehicles both sides of the pond. The Buick Riviera S and later the Mini Cooper S. They have high specific power (bhp/Ltr), with high thermal load, and need extra intake grills. To this day, it is surprising that the 1.6s Mini R53 has more total grill area than the original 4.0s XKR!

Jaguar Whitely refused to increase grill and sadly the testing was resourced. They sent an XK8 buck with AJ26s engine fitted to enable AC Hose design and I remember seeing the cooling pack just didn’t fit. The Oil cooler was touching the lower bumper skin.

It was later found out that some bright spark at Mira got a test pass with the bonnet open. Apparently, this was the birth of the bonnet louvres to increase air flow through the pack – as they were never in the design. We also discovered some very discrete changes to the bumper skin. The upper inner mouth has recesses, and the very bottom edge has clearance cutaway for flow to Oil Cooler (So, its not advised to fit an early XK8 Bumper to an XKR).

Every time I see the front of my car, I remember how uncompromising Jaguar were to keep that small mouth and it tickles me when I see the later 2005MY version with additional under bumper grill that is completely superfluous!

 

Now this is in interesting. I love that they were uncompromising in the design of the car… and yet the rear end had to fit a couple of golf bags.


Could this information be used to apply for exemption from the front license plate rules in many states in the mainland US?

 

i don’t know about other states, but I’m confident that in Texas, which requires front and back plates, the DMV wpuld
give you the typical blank look if you tried to convince them a front plate needed to be deleted.

they rule their kingdom like it’s “Game of Thrones”

 

So glad I'm in PA where front plates are not required. Mine was a Jersey car and first thing I did when I got home was remove the front plate bracket. Its unfortunate but the standard front plate mounting really ruins the look of the car.