[[ A fellow Jaguar owner asked ]]
> Could you please describe the engine mods you performed on your V-12?
[[ And I responded ... ]]
The fuel injected 12 cylinder cars use a very small diameter
intake tube (3cm) feeding each air cleaner. However the throttle bodies
are nearly 8cm dia. This is to cause the intake air to flow at supersonic
speeds during wide open throttle, eliminating noise from travelling out of
the intakes. The result is a quiet(er) car when you mash the throttle.
Removing these small stacks in favor of some 8cm stacks proved to
provide additional pull in the 4000-5500 rpm range. Also, another thing
the engineers neglected was to gather cool air for the intake charge,
instead relying on post-radiator heated air to feed the intakes. Series I
and perhaps Series II V-12 sedans had this feature though. Soon I
will plumb the intake tubes over the radiator shroud so as to take
advantage of the cool air charge. (Increased density blah blah...)
Since here at the university we live 500 km from our parents'
houses, we make a lot of long trips. We travel between 100 and 160 km/h
for the duration. The intake modifications have very much helped the
high speed operation of the car. Now I just need an overdriving manual
transmission and all will be well.
Greg
Greg Meboe meboe@lestat.scs.wsu.edu
Web site>> http://www.scs.wsu.edu/~meboe
Dept. of Mechanical and Materials Engineering
Washington State University, Pullman, Wa.
'85 XJ-12 H.E. (daily) '67 Spit-6 '74 TR-6
Mail me: greg@meboe.com Return to Greg's British Car Homepage