delete......

 

Can you keep the stock height with PSS's? I have a C2S and the car already slighlty scrapes coming out of my driveway.

 

I traded my stock 19's for three piece 19's lighter in weight and from my experience since the three piece seem to have less mass and weight they don't absorb the road as much as my heavier stock 19's. I totally agree with the lighter the wheel the better the response. but there is a difference in the ride. good luck with the rest of the thread

 

Easy answer -- you need 18" wheels to clear the brakes. 18's aren't just the best for the track, they are the best for any 997... period. If you want the facts, do a search here and at RL and you'll find the quotes from the engineers, Porsche insiders, writers from all car magazines, race car drivers that compared 18s and 19s on the 997, etc. It's well known that 20's handle and ride worse than 19s, which handle and ride worse than 18s... If you happen to like the looks, then that's fine -- just don't discount reality and the original question of the poster.

 

Have 20's on my 997S. Don't notice much if any ride difference. Additionally noticed no difference on my 0-60 or 1/4 mile times using my GTech meter, in fact my best 0-60 time was with the 20's. This is based on my results, not just something someone has heard.

Has anyone weighed their wheels? My 20" rears with 305's come in at 58.5lbs. That not much more than stock, only 2-3 lbs difference.

 

A million things can change performance from day to day... Temperature, humidity, etc. You can run 0-60 10 times and get different readings. Physics, however, is physics.

My oem 19s are 44 lbs front, 53 lbs rear. My Fikse 18s with RA1s are 41 / 45 lbs respectively. With PSCs those figures would be less. 1 lb of unsprung weight (wheels/tires) is equivalent to about 1 hp of gain / loss -- so 58.5 lbs vs. 45 is as though I have 13.5 hp more. May not seem like much, but who wants less performance in a Porsche?

As for ride difference, I can tell you this, that the handling and ride increased substantially when I went from 19 to 18, as all of the reports, articles, etc. suggest.

 

How crazy is it that 18s are now 'little'? Like, the old 14s or so.

So do any of you have pics of 18s on your 997? I honestly can't get my head around that. Don't know why. Right now I think I'm just thinking about going to a very light 19. Thing is, all the ultra lights are one piece. Get curb rash and you're screwed.

 

45lbs is much lighter than than stock and I don't doubt you might have some measureable difference even if small or more. Since Porsche thinks 55lbs is fine for the stock setup. I'm not going to sweat 3lbs though as it's not much of a different and like mentioned, really not much difference in real world for me other than looks.

 

If all this is true that 18's are the best then why did porsche it's self go with 19's on their most prize possession.... the 997. I mean the new gt2 will have 19's right. I will bet that the new 998 will feature 20's then what will all say????

 

They built the car based around the wheel size, the suspension geometry and so on, same as wit the GT 996 cars and 18's and why most dont go to 19's... They didn't just slap them on

 

Big wheels on new cars due to customer demand (bling) and to get over big brakes (see Ron's post above).

Geez people, this is not a complex answer to the original question. See, by way of example, http://en.wikipedia.org/wiki/Unsprung_weight

"The amount of movement is inversely proportional to the weight - a lighter wheel which readily moves in response to road bumps will have more grip when tracking over an imperfect road. For this reason, lighter wheels are often sought for high-performance applications. In contrast, a heavier wheel which moves less will not absorb as much vibration; the irregularities of the road surface will transfer to the cabin through the geometry of the suspension and hence ride quality is deteriorated."

 

The history of 19s on the 997 is well documented on the web (this forum and Rennlist for example). The car is designed for 18s, which is why they are standard on the 997. When you option up to the S, you get the otherwise optional 19" wheels. Porsche engineers have admitted (international press) that the car is "best" with 18s, but that the marketing department pushed hard and thus instead of delivering S and GT cars with 18s, they put on the otherwise optional 19s. The oem 18s fit just fine over even the bigger brakes on the S, but bling is in so the 19s became part of the package.

 

ok all this sounds completely true and correct but cant and dont they make 20's that are lighter than the stock 19's. and if this were true would that make the 20's better...

 

As stated, tire diameter is the same for 18, 19, and 20" wheel applications. The front on a 997 is about 25.5" and the rear about 26.3". What that means is that with the outside diameter being constant, what you end up with is less and less sidewall as you go from 20" to 19" to 18". As engineers report, there is a falling off of benefit of a stiff sidewall. You want some flex so that your tire somewhat conforms with the pavement vs. being so stiff and hard as to be lock a hockey puck, which would just skip across anything imperfect. As R&T engineers explain (as do others), there's a ramping up from 16 to 17 to 18, which really is about the pinnacle of grip and ride, then a falling off as you go to 19 and even worse 20. With this falling off comes a much worse ride, less grip (as outlined), more potential for damage (less sidewall to absorb impact from potholes, etc.), and on and on.

It appears the media convinced some that bigger wheels is cooler, some wheel makers saw the opportunity and made them, but those sources are not explaining the downside, which probably explains why I keep hearing of people buying 20s and getting rid of them (or 19s and changing to 18).

 

Tires will make a huge difference in comfort and ride quality . So far the best in my opinion is the Michelin pilot sport 2 . The wheel weight will also make a small difference .You can keep the 20" wheels and simply change to a lightweight forged 20" wheel . Champion has a few and HRE is in the process of making a new 1 pc forged wheel that is very light .Wheel weight is unsprung weight so it will also make your feel quicker .

I thought i read you wanted to sell your car w/ the supercharger how much do you want for it ? Kinda too late i bought a 06 c4s last week .I will be loading pictures soon . sport seats painted white ; white console and trim ; illuminated door sills , etc...