Lowering unsprung weight

[wallisj]

When i was looking for my new alloys (again) i was talking to one of the chaps at Ripspeed (whom i do actually trust) and he mentioned that "roughly" every 1kilo you shed from the driving wheel is like removing 14kilos from the overall weight.

Can anyone confirm whether this is complete crap or has some glimmer of truth cos my new 17" superleggeras are 7Kilos each versus 17.5 for either standard 16" or 17" superTs

So i am saving at least 10kg from each wheel plus the 17kg from spare so i have already lost 57+kgs from the car but mostly from the wheels.

This should improve power to weight plus losses in moving wheel???

Thanks for anything

Jamie

 

[BenR]

haha, its not reallt that easy. It should be about 10 kilos per kilo lost on unsprung weight. But this only really applies to any rotating mass such as wheels tyres, brake discs drive shafts etc. And any stuff that forms part of the suspension, it get a bit harder. Dunno if you truly will notice the 40 odd kilos missing from the "unsprung weight" and the spare dont count, its not spinning, so you would of just lost 10 kilos. Also, it wont improve power to weight ratio, but put less strain on the engine, and requre less power to spin the wheels, and so you save more power, which can then be used to actually propel the car....

 

[wallisj]

That was my thinking...

at least i am over 1/2 way to the weight saving the renault boys did to get the cup version...and i didnt lose my toys.

I was hoping that the main difference would be the 1/2 weight saving on the power to move the alloys cos i did notice a difference when a friend put 17"s on his saxo from 15" was well slow.

ta
J

 

[Fred@BTM]

JAMIE!!!!! Dont tell me you got your wheels from Rip(off)speed!!!! How much did you pay????

 

[wallisj]

No i didnt....got them from demon tweeks

They were over 800...rip(off) speed originally wanted over 1100

but demon tweeks made a screw up so i got a set of top notch locking wheel nuts and a couple of other things for nowt
we like

Although i have to wait until wednesday for them rather than today

Ta
Jamie