Is this true?

[winkle57]

http://www.potn.co.uk/lightweight_wheels.php
The bit about rotational weight?

 

[theduck]

have certainly heard similar comments made by respected members on here

 

[Inferno]

Think of each wheel as a flywheel, now read this:

http://www.uucmotorwerks.com/flywheel/how_a_lightweight_flywheel_works.htm

 

[White16valver]

I believe it's the case.

They also help handling as your suspension isn't trying to control so much weight, therefore it may feel more nimble in the corners.

 

[theduck]

lighter brake discs will have the same effect as lighter alloys.

lighter brake callipers will help with handling also because of less unsprung weight

 

[clio_luke]

ultraleggera's have made a difference in the way my car drives.
snappier acceleration, turning.
a lot less brake fade!

 

[winkle57]

lighter brake discs will have the same effect as lighter alloys.

lighter brake callipers will help with handling also because of less unsprung weight

Where can you buy said callipers and discs? I've read a lot of threads on shedding weight and haven't heard of anyone using lighter discs and callipers.

 

[Inferno]

Think you'll be lucky to find lightweight disks and calipers, I really don't have a clue if the likes of AP or Brembo kit offers any weight loss. At a guess I'd say no, purely on the basis that most aftermarket brake kits are physically larger than the stock items.

Your best best at reducing unsprung weight would be wheel choice and if you're going to be looking at grams - wheel bolts!

Written for hot rodders, but more info here:
http://victorylibrary.com/mopar/sprung-c.htm