Unsprung weight, how much diiference

boraboy · Post by **boraboy** » Fri Dec 28, 2007 8:46 am

I've got a couple of pairs of AP 4 pot calipers, they came off a Land Rover and are made from cact steel so are quite heavy when compared to the Ali versions.

Would this cause any problems if I fitted them to either my Bora or my mk1 golf.

They will fit onto a 312mm disc which is bigger than the standard I have now.

Pike · Post by **Pike** » Fri Dec 28, 2007 9:32 am

They'd kill the MKI handling! I'd put the on the Boara as the effect wouldn't be so noticable and its heavier to start with and can do with the extra help slowing down.

boraboy · Post by **boraboy** » Fri Dec 28, 2007 2:06 pm

OK, thanks Pike,

I've also got a set of G60's to go on the mk1 so will probably use them on that.

Vectraman · Post by **Vectraman** » Thu Jan 03, 2008 4:52 pm

One of the Jap mags ran an article on their scooby project stating that 1kg of unsprung weight saved was the same as 10kgs of kerb weight.

Rule of thumb i suppose but should think that adding unsprung would be along the same lines gains-wise...

Mr Fletcher · Post by **Mr Fletcher** » Sat Feb 16, 2008 1:45 pm

is there any chance somebody could give some more detail on the unsprung weight issue ie cause and effect.

i just went and looked at some 330 calipers and discs to upgrade my e36 but i didn't buy them because

amongst other issues they were damn heavy. :roll:

cheers

jason

ScoobieWRX · Post by **ScoobieWRX** » Sat Feb 16, 2008 1:59 pm

If you're really keen to lose weight on the brakes why not look at some of the Brembo cast Aluminium calipers and floating Rotors. Better braking, better feel and lightweight too. Add to that some ceramic brake pads and youre away. Not cheap though so i suppose it depends how much you can spend. I've been looking into performance friction too, recommended by Duncan and Zen Performance. They do the Aluminum calipers and floating rotors, not as much money as Brembo or AP.

P.S. I hear people raving about the K-Sport kits too, and very very cheap for what you're getting!!

Mr Fletcher · Post by **Mr Fletcher** » Sat Feb 16, 2008 2:08 pm

yes i also run performance friction on my 03 sti and rate them very highly. i was just looking at my

options really as my brakes on the track e36 will need replacing after my next track day , i have noticed the

ksport but although it was more than i wanted to spend at the end of the day they do look good value.

cheers

jason

duncan · Post by **duncan** » Sat Feb 16, 2008 2:10 pm

sidewaysfletch wrote:is there any chance somebody could give some more detail on the unsprung weight issue ie cause and effect.

As suspension moves the work of the springs are there to absorb the shock - when deflected the spring pushes up on the car and the 'sprung' weight. When the weight of the 'unsprung' items is less the spring has less mass to stop moving upwards and can therefore keep the vehicle better in contact with the road.

It is a huge subject though but well worth investigating.

Some basic info here:

http://en.wikipedia.org/wiki/Unsprung_weight

duncan · Post by **duncan** » Sat Feb 16, 2008 6:07 pm

Found this article that explains it properly.

Well worth reading :thumb:

http://www.autospeed.com/cms/A_0193/article.html

Mr Fletcher · Post by **Mr Fletcher** » Sat Feb 16, 2008 6:16 pm

very interesting you can quite easily take one step forward and three steps back :roll:

thanks for digging that out

cheers

jason

Bigpower

Unsprung weight, how much diiference

Unsprung weight, how much diiference

Great Article on it