Well the weight of a stock Pov pack 1000 tudor has always enterntained me.
 
I got my Pov pack 2 door sedan down from 625kg to about 596-605kg at one point
with the next owner going a bit further but yet to finish.
 
cut up bumpers to bumperettes -4kg
little agm battery -4.5kg (now lithium available) original factory 10.3kg!
renault alloy radiator -3kg
Sigma/1200 disc setup at the front -2kg
removed all the inner tar -2.5kg (anal not worth the effort!)
swapped to modern alternator and starter -2kg
Mercedes 250ce rear boot handle -230g (well worth it! orignal is 430gsm
Alloy grille instead of Stainless -1.3kg
no rear seats -3.5 kg
spare wheel replaced with 14 x 4 inch billet dracing front runner & saab tyre -2kg
billet alloy steering wheel 1.3kg
13 x 5.5 magnesium 6 hole jelly beans 165/65/13 (no change in weight)
 
around 600kg
 
New owner had put a lighter 1.6 baleno/vitara setup with light quad bike carbs,
1.3 sierra gearbox 5sp and crazy billet alloy/steel hybrid one off 2.5kg flywheel
-26kg from complete original A10 and 56a 4 speed
 
new weight around 570kg but 140hp ate

Now to go even further would be nice to use something like this front suspension
and also the same for the rear which would shave another 60-70kg from using
factory front and rear but none of us would be crazy enought to throw that money on a 1000
 
titanium 6.5kg subframe! titanium hubs and Wishbones and more
 
http://www.force-racing.co.uk/front-suspension/