986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - Faster time from .. lightweight wheels .. or suspension ?

vijen6 · 06-19-2013, 07:10 PM

They're not, its the type 371 .. however seeing those weight numbers was shocking. I thought they were heavy so I said 25# range but .. jeeze !

Correct me if I'm wrong but ..

1. Conventional wisdom says 1# rotational / unsprung weight = 7# sprung weight.
2. Conventional wisdom also says every 6 lb lost is similar to gaining 1 HP.

TE-37 in 18x8.5 is just under 17.5# and the 18x10.5 is just under 19.5#. Assuming 30# for my current wheels .. that's rough about 10# rotational mass X 4. A total of 40lbs rotational mass total difference.

Applying conventional wisdom rule 1 would mean the new wheel will feel like driving a 280# lighter car.

Applying conventional wisdom rule 2 would mean the new wheel will feel like the car has 46.6 more HP !?!

Definitely sounds like I'm going with wheels first.

06-19-2013, 07:10 PM	#4
vijen6 Registered User Join Date: Jul 2006 Location: san jose Posts: 225	They're not, its the type 371 .. however seeing those weight numbers was shocking. I thought they were heavy so I said 25# range but .. jeeze ! Correct me if I'm wrong but .. 1. Conventional wisdom says 1# rotational / unsprung weight = 7# sprung weight. 2. Conventional wisdom also says every 6 lb lost is similar to gaining 1 HP. TE-37 in 18x8.5 is just under 17.5# and the 18x10.5 is just under 19.5#. Assuming 30# for my current wheels .. that's rough about 10# rotational mass X 4. A total of 40lbs rotational mass total difference. Applying conventional wisdom rule 1 would mean the new wheel will feel like driving a 280# lighter car. Applying conventional wisdom rule 2 would mean the new wheel will feel like the car has 46.6 more HP !?! Definitely sounds like I'm going with wheels first. Last edited by vijen6; 06-19-2013 at 07:29 PM.