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Old 06-19-2013, 11:13 PM   #6
Topless
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Join Date: Nov 2006
Location: Southern ID
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Quote:
Originally Posted by vijen6 View Post
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.
It is possible to overthink the wheels a bit. Smaller wheels will be faster. Again, choose tires first, and then match wheels to the tires. a 10.5 rear sounds too wide for a podium AX car. Top drivers are running 245/265 or 255 square. 8" and 10" should be plenty of wheel.
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Last edited by Topless; 06-20-2013 at 06:57 AM.
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