18" vs 17"

Jack K · 03-20-2004, 12:41 PM

Any opinions regarding these issue:
looks; handling; aquaplaning; weight; feel; strenghth

Bill Verburg · Bill Verburg's Garage

Street or track or combo? How are the roads?

For track there is a better choice of 18" rubber, for combo 17 is probably better and there are some interesting options.

Jack K · 03-20-2004, 09:06 PM

Bill ... ostensibly for everday street use

Bill Verburg · Bill Verburg's Garage

The main knock on the 18s for the street is the vulnerability of the rims to pothole damage. The 17s aren't going to be quite as susceptible to that sort of thing.

FisterD · 03-22-2004, 01:38 PM

I prefer the look of the 18's. You may lose a little ride quality, but not much. I also believe the 18's handle a little better, with the lower profile tire.

Jack K · 03-22-2004, 01:58 PM

This all started for me when I bought the car 3 weeks ago and believed that the shocks needed to be replaced - I was disappointed with the ride generally. The mechanic checked and confirmed that they were very bad, needed replacement and put in new Konis front and replaced the complete rear strut assembly.

I have been driving the car now for a couple of weeks and am still disappointed - it is firm to the point of being uncomfortable and I was wondering if the wheels are compounding the issue. Maybe I just have to get used to it ...

maxnine11 · maxnine11's Garage

Hi Jack,

Some people say they do not notice the difference between 17s and 18s.
Most of the cars that i drove when i was shopping had the 17 inch cup wheels, and rode rather nicely (using my lowered SC for reference).
I ended up buying a '97 "S" with 18" hollow spokes with S-02s. the ride was a lot more harsh IMO. being somewhat uneduacated at that point, i though that the S had different spring rates than the regular model. Learned later that the suspension is exactly the same.
If your car has more than about 40k miles , the original shocks/struts are probably spent. although, this is usually felt in more of a floaty, unconnected feeling than a harsh ride.
If the roads are rough where you do most of your driving....or you do not do auto cross, D/Es, or drive super-aggressivley, then you should consider getting some 17s.
Make sure that you go with the same overall diameter as the 18s so that you gain some sidewall height for a bit of a cushion.
A couple of added bonuses with the 17s:
-easier to find a strong light wheel.
-tires themselves are lighter
-tires are cheaper when it is time to replace.
The original 17inch cup wheels can usually be found quite cheap, and were the standard wheel for our "S" models (from the factory with a spacer on the rear)

good luck, and keep us posted!

max

trader220 · 03-23-2004, 05:11 PM

I had 18's on my C2S and they looked great but they ride like a tank. You'll know when you roll over a dime in the road. I am sure they're better on the track but its a huge trade off in my opinion. The price difference in tires is big too. I've had 16's on my 89 and earlier NA cars and 17's on all my other 964's. Of course the 17's on the turbo too.

m325ix · 04-08-2004, 07:57 PM

Quote:

Originally posted by Jack K
This all started for me when I bought the car 3 weeks ago and believed that the shocks needed to be replaced - I was disappointed with the ride generally. The mechanic checked and confirmed that they were very bad, needed replacement and put in new Konis front and replaced the complete rear strut assembly.

I have been driving the car now for a couple of weeks and am still disappointed - it is firm to the point of being uncomfortable and I was wondering if the wheels are compounding the issue. Maybe I just have to get used to it ...

hmmm... you know you are driving a porsche and not a lexus, right?
My car is lowered even lower than the Eurospec ride height and I run 17" Rufs (in place of factory 15" fuchs) and my ride is just the way it supposed to be - sports oriented, road hugging, anti-sleep smile making...