Ride quality 996

[sparks2728]

Hi there

I'm new to the site and have a standard 2003 996 C2. It runs on 18 inch wheels and the usual 225/40 and 285/30 tyres (P Zero rossos). However, on the British country roads, the ride is harsh to say the least and as the car has more than enough grip i am contemplating sourcing some original 17 inch rims and reverting to the standad 205/50 (f) and 255/40 ® tyre sizes. Can anybody advise if they have done this and whether (in reality or theoretically) it's going to make a big improvement!?

MN

[chriswaxman]

I have a 1999 C2. When I purchased the car it had 18" wheels. I currently use the car as a daily driver. I mounted a set of 17" C4 rims with snows in the winter. When spring came I decided to mount summer tires on the 17s. The difference in price between 17" and 18" tires is significant. And with 17" tires you can find some good ones that even come with a mileage warranty (at least here in the US).

To respond to your question: The ride quality is quite nice on the 17s. It was definitely softer with the 17" snow tires. I tend to think its a bit more comfortable with the 17" summer tires as well, compared to the 18s. That said, there is a noticeable difference in handling between the 17" and 18" wheels. With the 18" wheels it felt like a racing car. With the 17" wheels it feels like a sports car. With the 18s it felt like there was zero body roll. Which is good. With the 17s the handling is a bit more "lively" and you can feel some roll. You can also pitch it around and feel like you're approaching the limits at lower speeds than the 18s, which isn't necessarily a bad thing!

Regardless, I've really impressed with the ride quality of the 996 with 17s or 18s, even with snow tires. Handling is amazing and the car is comfortable. To me that's what makes a really good suspension.

I just had an alignment done and the 17" tires are wearing well. (Falken Ziex) Overall I'm happy with them, and they suit my use of the car. And the thought of having to buy a set of 18s every 6-12 months was just too much too bear. I still have the 18" rims and may put them on if I plan to do a spirited driving trip or an autocross.

Edited June 14, 2009 by chriswaxman

[RFM]

Believe it or not, Porsche's equipped with the standard wheels have a better drivability, comfort and are less fatigue on PUBLIC ROADS under all circumstances since the SC series (ROW suspension). Besides much less expensive.

[GranburyChuck]

I am experiencing the same issue on my 2000 C2 daily driver. The rodes are not great. Part of my issue is probably suspension. I have 120k miles on the car and probably original shocks. I ordered the ROW suspension and will start to put it on today. Others have commented that they gave better ride than original US spec but probably had degraded suspension to begin with. Tires is also an issue. Seems whenever I buy new tires (had the car 2 years, put 56k miles on it, and replaced 4 rear sets of tires, long story). Initially, any of the tires I tried (I am on 18's as well) were fairly low noise. After little wear they all got very noisy. I even put sound deadening all in the back and hasn't quelled the noise much. Personally, I am wondering if the tires with parallel grooves (follow road direction) versus chevron type (cross pattern) provide less noise. Next time I will try the OEM Continental tires with parallel grooves. I have pondered the same thing you are suggesting, switch from 18 to 17, but will try the suspensioin first.

[BruceP]

You might be surprised at how good they are. Bigger wheels don't offer a handling advantage other than on the smoothest pavement. The opposite, in fact. They're a fashion statement, but the reduced sidewall height robs the car of some ability to soak up small irregularities. The dampers end up having to do more work for which they weren't really optimized. From a pure performance point of view, everything I've read says that 18" is the best compromise for looks and performance on a 996, but 17" wheels on real world roads are functionally superior.

[Jon996]

Ah, it sounds like your roads are much akin to the roads here in Minnesota! I have little to contribute to the above, other than you might consider looking for discussions on tire (tyre?) pressure. I had the same feeling when I purchased my car, and reduced tire pressure a little (32Front, 40 rear). Surprisingly, this was also a recommendation from my dealer, and was even OK'd by the PCA.org team. There was quite an improvement.

There was more improvement when I replaced the tires with new ones, either just the extra rubber or the new brand (Michelin Pilot Sport 2) made an improvement.

The expensive last approach is to consider different shocks like PSS10s. I did this last, mainly for handling and control over ride height, but the ride seems much less jarring.

Edited June 13, 2009 by Jon996

[doug davis]

Hi there

I'm new to the site and have a standard 2003 996 C2. It runs on 18 inch wheels and the usual 225/40 and 285/30 tyres (P Zero rossos). However, on the British country roads, the ride is harsh to say the least and as the car has more than enough grip i am contemplating sourcing some original 17 inch rims and reverting to the standad 205/50 (f) and 255/40 ® tyre sizes. Can anybody advise if they have done this and whether (in reality or theoretically) it's going to make a big improvement!?

MN

1999 C2. I switched from 18" to 17" for daily driving and found the ride comfort to be much better here in NJ, USA where some of our secondary roads can be pretty bad. I wouldn't hesitate to make the switch, especially since I found quite a few sets of reasonably priced 17" OEMs available here and on other lists. The set I bought even came with a decent set of almost new rubber on them.

Doug Davis

[sanjeev]

Hi,

Assuming your suspension is in good order (this, I would say, is your first line to check),

then yes, I would agree that 17" wheels with more sidewall will provide a slightly better

ride. But, as the other posts have noted, ultimate handling response and grip will be lower.

That said, I replaced the original F+R struts, and run 17" wheels on the streets,

and am very pleased with the ride quality. Night and day difference with the original

suspension (at ~40k miles, probably not worn out, just worn). Switching to 17"

from 18" wheels had a lesser magnitude effect on ride, but still quite noticeable. I prefer

to run the 17" wheels for daily driving, and now only use the 18" for summer occassional

weekend drives (rarely!).

[jgriffin56]

I have/had the same problem in my stock 04 C4S with rough ride. Again consulting the PCA Tech site, I found out two things. One the european tire pressure system is set up in bars of pressure, whereas the USA is set up in lb/sq inch. It seems that "bars" do not allow much variance in pressure since they are set up in .5 bars and then converted to lbs/sq inch. Second, it is generally acknowledged that the car manufacturers use high tire pressures on new cars to get the roll needed to acheive high gas mileage numbers for the EPA. By reducing the tire pressure to 40 rear and 32 front, I have taken some of the harshness out of the ride and I am much more satisfied on the quality of the ride. Again IT IS A Porsche, Not a Cadillac.

[The Hoth]

Do you have a sport chasis package? Mine 03 996 C2 has it with the 18" wheels.

You feel everything (literally). Lots of feedback through the steering wheel.

Anyone has noticed the feedback through the steering wheel? I switch from the original tires to Bridgestone.

Road noises has been reduced significantly though.

[Benjamin Choi]

ride quality on my 19x12 with 25 profile tires on pss9s is excellent. firm and sporty just how a 911 should ride.

my toyota suv? super smooth, soaks up bumps. just how it should be.

[wwest]

I am experiencing the same issue on my 2000 C2 daily driver. The rodes are not great. Part of my issue is probably suspension. I have 120k miles on the car and probably original shocks. I ordered the ROW suspension and will start to put it on today. Others have commented that they gave better ride than original US spec but probably had degraded suspension to begin with. Tires is also an issue. Seems whenever I buy new tires (had the car 2 years, put 56k miles on it, and replaced 4 rear sets of tires, long story). Initially, any of the tires I tried (I am on 18's as well) were fairly low noise. After little wear they all got very noisy. I even put sound deadening all in the back and hasn't quelled the noise much. Personally, I am wondering if the tires with parallel grooves (follow road direction) versus chevron type (cross pattern) provide less noise. Next time I will try the OEM Continental tires with parallel grooves. I have pondered the same thing you are suggesting, switch from 18 to 17, but will try the suspensioin first.

I went through three sets of NEW tires before I came to realize that at about 8,000 miles each brand became uncomfortably NOISY.

'01 R/awd C4.

You might trying lowering the tire pressure significantly below factory specs temporarily with your 18" wheels to get an idea of the additional comfort level you might get with 17" wheels. But whatever else you do, DO NOT, NEVER, compare the Porsche's ride with a Lexus LS.

[sparks2728]

Thanks guys - I am not wanting a 'magic carpet ride' - I have a BMW E36 touring and an Audi A4 Quattro which are planty comfortable. It's just with 2 children under 6 and a wife - I try to use the 911 as much as possible on the weekends. Track days are not my thing - I would have bought a Caterham and raced it if I wanted a race car and I have competed in the past - I just want the 911 to ride as Porsche wanted (the cynice will say that they supplied 17s as standard so that people would pay the extra for 18s) but I cannot believe with all the R&D they did (including testing by former WRC Champ Walter Rorhl) that the 18s are a better road compromise than 17s.

I' off to lower the pressures before getting some 17s though!

MN

[beauar]

to put my opinion in perspective here is what I am running. I have a 2003 996 C2 with 225/40/18 front, 285/30/18 rear. They are the light alloy rims. I have stock suspension. I live in chicago where the roads are some of the worst....period. The car is very tight and you can feel every crack. This is completely normal with the low profile tires. If you want a smoother ride you should change to 17 inch with a higher wall. They make a huge difference. the feedback in the steering is something that every driver should feel. It is a sign that Porsche knows how to build a true sportscar. I can't imagine a day without my 996. Simply the best car out there( for the money of course). I have driven vette's and wouldnt give my car up for a second.

[minny]

My'99 C2 Tip had the original 17s on with Continental SportContact 2 tyres and it rode well. The steering was more talkative and sensitive. The car was also more adjustable on the throttle. I upgraded to 18s with Continental tyres again purely for cosmetic reasons and the trade off was the steering becoming a bit numb and the secondary ride poorer. However, it still rides well compared to other performance cars. Outright grip is also slightly better but you really have to be pushing it to feel the difference. Proabably not noticable on a day to day basis.