Jaguar Forums - Jaguar Enthusiasts Forum

Hello Everyone,
I just bought a 3 litre manual as a winter beater. Trucked it up from the south. No Rust.
I will make sure the sills are looked at so they DO NOT rust- if possible.
'I was heavily involved in the development of this car, and the X400 R and the X400 SVO "supersport' (which used the X600 'F type' N/A powertrain). None of the latter came to frutition unfortunately.
Been scanning the forums here and have picked up on some serious errors. Some from know-it-all over confident members. Not one to nit pick but I don't like seeing false info sent out. Count your lucky stars Im not naming and shaming ;-)

Exhaust system on the X type is seriously compromised compared to the 3 litre S type and serious improvements can be made. Back pressure on equivalent S type- is around 230-300 mbars (depending one emissions spec of whether its an X200 or a 202), the equivalent X400 is almost 700 mbar on one bank and almost 600 mbars on the other. Terrible!
The Exhaust system on the 2.5 and 3 litres really need to be seperated - at least up to the rear tank. This will boost low speed torque significantly. This wasnt done due to the parent companys non sensical guidelines , which were common with huge heavy duty trucks and their 4WD whirling props and associated design envelopes required
Transfer case issues are due to lubrication contamination and/or leakage. This doesnt mean the design of the transfer care itself is weak- if kept cool and lubricated. Think of root cause and dont pin any/every kind of failure to it!
The intake manifold design with the IMTVs dont tune as well as they do on the X202 S type. This is due to package and an inept project management team at the time. I wish an X202 intake could be re- fabricated
The 60mm throttle is way too small- and this is done for idle speed control. 68 mm for performance use would have been nice
The engine is NOT a Mondeo engine or even a ST220 engine, the Ford engine heads have a deeper slower combuston chamber and the ports arent as good, the valvetrain is DAMB on the Jag, the pistons, rods and windage tray are all unique as are the cams, tappets etc. I was involved in alot of that and my pay cheque always said Jaguar.

The last time I drove one was a prototype- I'm most impressed with my car. Much more refined than I remember! The steering is responsive , more so than my XJR, and a little more feel than my Aston Martin Vantage but still not nearly enough. Car feels fairly agile. Engine is peaky- but I always knew that ( I can rectify that with some mods). I'm impressed with the dynamics of the car considering- the CD27W/CD132 platform isn't a bad one, the X type is really torsionally rigid for the time- but the battery couldn't be relocated. As a result- the front weight bias is 60% while the torque to the rear on the early viscous cars , was up to 60% to keep the RWD feel. The result is quite good. However there's ultimately no getting around the fact that the yaw inertia of the car relative to the centre of gravity, or the 'dynamic index' isn't as optimised as other performance machinary, like an E46 BMW, or even an X308 or X100 Jaguar. In the big picture, with the right tyres and correct spring/damper combo- this isn't such a big deal. I mean Audis do Ok and they are TERRIBLE in terms of layout!

Now I have to fight myself to focus on my real car projects and not build my own 'super sport' from my experience, and keep this relegated to the winter beater category!