So im picking up my 97 XJR here in about 2 hours. I am courious as to what to look out for on these?What the motor and trans can handle when adding power.What gears are in the rearend?What trans is in it ,what needs to be and should i look at when i get it to make sure the maintinace is up to date? Someone told me something about belt tensioners like to go out? Also is the s/c internal oiled? what about adding or does it already have a intercooler? CAI are they worth it? I was thinking of doing exhust,pully swap,tune,and meth if nessary? would like to see 400 at the wheels.......So any help or pointers would be awsome guys! This is my second jag i had a 86 XJ6 loved it but had trans problems so i sold it for the stang then that bug attached itself.So the jag will be my dd all the modding is on the stang!

 

Hi Badcat. The car does come with an intercooler, and the supercharger has its own oil. there is a small plug on the top that is removed with an Allen wrench. I have not re-newed mine, it's on the list though. I think if you decide to re-new the fluid, you need to suction out the old with a syringe and a length of plastic tubing. also, "XJRengineer" sells a mod that is a CPS bracket which advances the timing. I've put one in my car, and I did notice a difference in responsiveness. too early to tell about mileage improvements, but others have said they've gotten as much as a 2 or 3 MPG improvement. As far as other HP mods, I only know of a larger crank pulley for the S.C but I'm sure there must be others. Oh there is also a "blanking plate" for the S.C. that may or may not ad power, but accents the whine of the S.C. I learned about this on the XJR6.com forum.
The transmission is a GM 4l80e, it can handle a lot of HP and torque. Its also got some Japanese electrical components, such as a Nippon Denso alternator. So, even though the car is proudly made to exacting standards in Coventry, by Brits, Ford decided to put a Chevy tranny in the XJR's and A (at least partly) Japanese electrical system. So far, different techs and sales people selling Jag parts say that the x300 Jaguar is the best made series that was ever built.
Some of the weaker parts are the cup holder, the clock readout, and the Radio. Have fun with it, they are fantastic cars. Mike

 

Hummm bracket to advance the timing?! Do you have pics of this piece? Also why do people remove the rear mufflers? The blanking plate sounds like a cool mod,also what size and type of s/c is on these cars?

 

3.27 limited slip





'Bout the same as any other car; nothing exotic about it: change all fluids and filters, repack front bearings, check brakes, etc

How many miles on it? If over 100k take a good look at suspension bushings, shcoks, etc





Sometimes the timing chain tensioner gives trouble...clattering noise. The idler pullies for the drive belts often suffer bearing failure----"gravel" noise when engine is running



400 horsepower *at the rear wheels*? That's, what, like 600 horsepower at the crank? Ain't gonna happen....at least not with the (very limited) bolt-on performance parts available for this car.





Cheers
DD

 

The XJR/6 used a 3-pass rear muffler (versus 2 pass on the regular Xj6) so there's a bit of restriction. Lower restriction mufflers help a bit. I'm not personally aware of anyone running *without* rear mufflers. That would be awfully loud




Eaton M90


Cheers
DD

 

Stand-alone and installation pics here:
https://www.jaguarforums.com/forum/x...nigines-66536/

 

Thanks doug! And 400 to the wheels isnt 600 at the block! It would be right around 450/475 at the block.

 

Yeah, I was a bit off.

The (very broad) rule of thumb for an automatic transmission cars is 18-23% loss. Since the 4L80E is notoriously parasitic, if we take the higher end of the scale you'd need 520 crank hp to yield 400 at the rear wheels.

But even 450-475, as you mention, would be 40-45% increase over stock and a stretch for these engines, I think.

Hopefully XJR Engineer will chime in. His XJR/6 is fairly highly modified and I'm sure he has some dyno stats

Good luck with the car. I'm sure you'll like it. Nice combination of power, luxury...and price :-)

Cheers
DD

 

well this is my DD. I have a 91 SSP mustang puyshing close to 650 to the ground, sportin a 408 with a 76mm