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What's wrong with 17" wheels?

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Old 02-02-2010, 11:02 PM
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BruceP
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As I recall, 17" was the default size around which the suspension was designed. In other words, all other things being equal, the car will handle better on 17s than 18s in real world street driving (flame away, I'm sure there will be lots of argument on this point).

Tires are a component of suspension design. Decisions are made about shock valving and damping rates based on certain assumptions about how resilient the 'passive' suspension of a tire is, and how much unsprung mass is in the wheel and tire package. The less resilient it is, the more the shock has to be designed to cope with smaller, higher frequency bumps, which forces other compromises. In addition, a bigger wheel usually means more unsprung weight, which also asks the shocks to do a job they weren't really optimized for.

A lot of 996 folks believe - and I do, too - that the 18" wheel is the best compromise between handling and looks. But on a stock suspension, it's not strictly the best handling. If you're not fussed about the looks, you can feel very good about staying on 17s, IMO.
Old 02-02-2010, 11:39 PM
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911FM
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Happy with my 17s so far. Will see on the track end of March...


FM
Old 02-03-2010, 07:44 AM
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Barn996
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Originally Posted by BruceP
As I recall, 17" was the default size around which the suspension was designed. In other words, all other things being equal, the car will handle better on 17s than 18s in real world street driving (flame away, I'm sure there will be lots of argument on this point).

Tires are a component of suspension design. Decisions are made about shock valving and damping rates based on certain assumptions about how resilient the 'passive' suspension of a tire is, and how much unsprung mass is in the wheel and tire package. The less resilient it is, the more the shock has to be designed to cope with smaller, higher frequency bumps, which forces other compromises. In addition, a bigger wheel usually means more unsprung weight, which also asks the shocks to do a job they weren't really optimized for.

A lot of 996 folks believe - and I do, too - that the 18" wheel is the best compromise between handling and looks. But on a stock suspension, it's not strictly the best handling. If you're not fussed about the looks, you can feel very good about staying on 17s, IMO.
+1...I thought I was one of the few still running with 17"s.
Old 02-03-2010, 08:14 AM
  #19  
frankfast
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Originally Posted by BruceP
As I recall, 17" was the default size around which the suspension was designed. In other words, all other things being equal, the car will handle better on 17s than 18s in real world street driving (flame away, I'm sure there will be lots of argument on this point).

Tires are a component of suspension design. Decisions are made about shock valving and damping rates based on certain assumptions about how resilient the 'passive' suspension of a tire is, and how much unsprung mass is in the wheel and tire package. The less resilient it is, the more the shock has to be designed to cope with smaller, higher frequency bumps, which forces other compromises. In addition, a bigger wheel usually means more unsprung weight, which also asks the shocks to do a job they weren't really optimized for.

A lot of 996 folks believe - and I do, too - that the 18" wheel is the best compromise between handling and looks. But on a stock suspension, it's not strictly the best handling. If you're not fussed about the looks, you can feel very good about staying on 17s, IMO.
I thought so. Thanks for the explanation.
Old 02-03-2010, 09:58 AM
  #20  
ivangene
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Originally Posted by s_kelly
Living in an urban environment and rolling 18's, I'd almost prefer 17s. Last summer I bent a rim and trashed a sidewall while parking - never seen anything like it. Hit the curb with rear while parallel parking (super slow parking speed - <2mph). I'm thinking a higher sidewall might have prevented that.

not to be mean, but I think missing the curb would have prevented that
Old 02-03-2010, 02:13 PM
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450knotOffice
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Originally Posted by Barn996
+1...I thought I was one of the few still running with 17"s.
Nope. I have the 17's too (although I'm Jonesing for the 18" 2002 Carrera lightweights).
Old 02-03-2010, 03:12 PM
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roadsession
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The 3 Mk1 996 owners I know that still have 17s are saving money for 18s
For me - the visual difference is VERY BIG and I like my 18s.
When I see one with 17" wheels I just think it looks a little old school and doesn't fill out the wheel well quite enough...
Old 02-03-2010, 03:18 PM
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Doug996InKC
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The problem w/ 19s is, I can't find anybody with accurate alignment specs. Loren @ renntech says they don't exist for 19s, and he uploaded a scan of the 17s & 18s ROW, etc. specs. So why do Champion Motorsport and others make these 19s without alignment specs?

QUOTE (Doug996InKC @ Nov 9 2008, 11:05 AM) *
I too have PSS9s. My wheels are Champion Motorsport 19" RG5 (staggered). Loren should I use the X74 specs, even though they're 19" wheels? Thx!

You will never find specs for the 19" wheels on a 996 series car because Porsche does not approve them.
You could use the 997 specs but that would be a little misleading also because 997 has a stiffer chassis than 996.
I think that would depend on where the PSS9's are set for ride height. If you are 30 mm below stock then use the X74 settings.
Otherwise you will likely have to adjust to the ride height, and guess the settings that work best. - Loren
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Old 02-03-2010, 05:57 PM
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AndyK
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I use 17's for winter, and they are fine. I just like the way the car handles with the larger summer tires and 18's. Looks less dated too.
Old 02-03-2010, 06:29 PM
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Barn996
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Originally Posted by 450knotOffice
Nope. I have the 17's too (although I'm Jonesing for the 18" 2002 Carrera lightweights).
Very good choice.
Old 02-03-2010, 11:14 PM
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Originally Posted by BruceP
As I recall, 17" was the default size around which the suspension was designed. In other words, all other things being equal, the car will handle better on 17s than 18s in real world street driving (flame away, I'm sure there will be lots of argument on this point).

Tires are a component of suspension design. Decisions are made about shock valving and damping rates based on certain assumptions about how resilient the 'passive' suspension of a tire is, and how much unsprung mass is in the wheel and tire package. The less resilient it is, the more the shock has to be designed to cope with smaller, higher frequency bumps, which forces other compromises. In addition, a bigger wheel usually means more unsprung weight, which also asks the shocks to do a job they weren't really optimized for.

A lot of 996 folks believe - and I do, too - that the 18" wheel is the best compromise between handling and looks. But on a stock suspension, it's not strictly the best handling. If you're not fussed about the looks, you can feel very good about staying on 17s, IMO.
+2
Old 02-04-2010, 12:47 AM
  #27  
Darren
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Originally Posted by RallyJon
On dirt/gravel, roughly equivalent to 205/65-15. On tarmac, roughly equivalent to 225/40-18.
Eh?

17" have a lot more sidewall flex which feels like sloppy soup. I would always run them on the street with track suspension and that was a nice compromise.
Old 02-04-2010, 07:45 AM
  #28  
Doug Davis
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Originally Posted by PasPar2
from the success I had selling my 17" inch wheels for close to nothing... I would say there is EVERYTHING wrong with them simply due to the fact that now one wants them at all.
I love 17"s on my C2. The ride is worlds better for everyday driving. I use the 18" set I have for track days only.

In fact I'm looking for another set of factory 17"s to buy if anyone selling right now!

PM me...

Doug
Old 02-04-2010, 11:12 AM
  #29  
RF5BPilot
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I bought my car used, it came with 18's. Given the relatively rough roads around Seattle, had I spec'd the car from the beginning, I would have chosen 17's. I would opt for a reasonable ride and better protection for the wheel and suspension over looks. Any day.

If you live in an area with very smooth roads and you want to pay more for the wheels & tires to get a particular look, then those are entertainment dollars. If they're that entertaining, go for it.
Old 02-05-2010, 07:47 AM
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frankfast
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With the help of all the opinions here I bid on a set of Carrera III 5-Spoke wheels on Ebay last night and won. I decided that style was important enough to take the plunge. I'll need spacers and then decide on rubber. Can't wait to see how they look and feel.


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