XJ-12

I immediately did a couple of simple things, Magnecor race wires, K&N filters, Platinum +4 plugs etc. A free flow stainless exhaust with some high performance cats would help with probably another 20 HP also, although I have not done this as yet, it is on my agenda.

Twin supercharging ( you would have to do twin the way the engine is set up) would be prohibitively expensive, but it has been done before. They also sell some bored out and honed twin intake manifolds for this car.

With 320 HP and 350 LbFt torque on tap to begin with, and freeing up another 20-25 with minor modifications, I see no real need to go crazy with supercharging. Add a 50 shot of nitrous if you really need that extra oomph, the car is a kick just the way it is. Remember though, its a heavy 5,000 pound car, so engine mods have limited returns unless you cut some weight out of it. And that defeats the whole purpose of being a Jaguar luxury sedan!

Daniel Arsenault
Lakewood, CA
1994 XJ12 Morocco Red

Tim,

Increasing the performance of V-12's is not a new topic. Take a look at the recent posts on the XJS topic on this website. I assume that most of the things that are said about the XJS V-12 will apply to the XJ-12 as well.

In a word, trying to supercharge an V-12 Jaguar is a difficult and expensive proposition. There are ways to enhance performance short of supercharging. Read the information related to the XJS's. It will give you a clue to how much of a problem and how expensive the undertaking can be.

Steve Weinstein
'72 E-type 2+2 (V-12)
'70 XKE FHC