Questions on the 2006 normally-aspirated XJ:
1) The horsepower rose to 300 from 294 and the torque to 310 (from 300?). How did they achieve this? Also, I notice this is certified as an Ultra-Low Emission Vehicle. Was this the first year for that rating and was it related to the change in horsepower?
2) The highway mpg rating dropped from 28 to 27. Why? Was it related to changes in the engine that were related to the horsepower increase?
3) It adopted the acoustic laminated glass. What looks to me like a British press release stated this was used not only in the door glass but also the "windscreen". But in the 2006 US Product Guide it only mentions the door glass. Was it used in the US spec windshield? Also, this press release says the new glass reduced the decibles inside by five (a significant amount, though they don't say under what conditions). Do you have any idea if the US spec car experienced this kind of noise reduction? Or in any event, when you drive a 2006 can you tell it's quieter inside?
Submitted by stevejag@sbcgl… on Tue, 01/15/2013 - 15:34
Edited on 2013-01-16 11:47:22
Edited on 2013-01-16 11:46:31
Wow! I guess you've been doing some homework, huh??
Off the top, I'd say you have all that pretty much right. There were numerous changes between 2005 and 2006; subtle though they were. The Engine Management system changed from the 32-bit Denso system to a corporate PAN-PAG system. This was necessitated by tighter EPA mandates for corporate emissions. There have been numerous, alphabet soup emissions levels that the mfg. has to meet. NLEV, LEV I, LEV II, ULEV I, ULEV II etc. The requirement got a bit more stringent for 2006, hence the lower MPG. Thank you, EPA!!
The glass did get laminated for 2006, but I think by 2008 they went back to the previous glass. As I recall it was a supplier issue.
If you like, post an email address, and give me a few days, and I think I can come up with documentation for most of your questions.
Cheers,