London Banter - View Single Post

Adrian · July 17th 08, 03:08 PM posted to uk.railway,uk.transport.london

(Andrew Robert Breen) gurgled happily, sounding much like
they were saying:

Except that they've also (in some cases) switched to aluminium monocoque
construnction, which should make them lighter, just as it has in cars
such as the Jaguar XJ and XK. I have an XJ, and although it's much
bigger and has more gizmos than my previous BMW, it's also a fair but
lighter, and gets away with a smaller engine without loss of
performance. But the aluminium trains are heavier and use more power
than their steel predecessors.

Hmmm..

1968 Jaguar XJ6 4.2: weight 1537 kg.

2008 Jaguar XJ-R: 1659 kg.

Much less of a difference than with the F*rds (much less of a difference
in NVH too, I'd suspect), but in spite of the XK boat-anchor in the old
Jag and the new 'un's alloy structure, the old'un is still lighter.

So: the aluminium cars are heavier and use more power than their steel
predecessors...

Small problem there... The X308 steel predecessor to the X350 ally XJ was
about 200kg heavier than the X350.

After the "Series" XJs, which would have steadily put on weight from the
s1 you quote above, the late '80s/early '90s XJ40 was north of 1800kg.