Vinnie

Hey All, I was wondering if there were any opinions on the handling difference between 17 inch and 18 inch rims? Are there any issues with a higher sidewall on a 17 inch rim, can you feel a real difference (lean)? All else being equal of course. :-)

The reason I ask is because with NYC streets/potholes, I think the added sidewalls will help numb the affects of the imperfect road. Although I have yet to road race the car, I will start to bring the cars to DEs et. al. this year, and wanted to know my best alternative. To use the 17 inch rims or 18s for road racing (one set street, the other race). I know the race tires are cheaper for 17 inch rims :-) Any help or input would be greatly appreciated.

As a side note, thanks Jen Munson for the behind the scenes work for this list, I got my rennlist membership (020223-3469) this weekend!

Kind regards,

993RS

IMHO: 18 inch rims give you a better turn-in and incisiveness. They will feel a little bit harder and perhaps noiser. It is a cost aspect. I personally prefer 18 inch rims, not only for handling, but also for looks (fills out wheel arches better).

Greg Fishman

Hi Vinnie,
Hope all is well.
There is definitely a difference between the 17's and 18's in overall handling. I did some back to back testing with a friend who is a pro driver. We both drove on the 17's with Hoosiers and then on the 18's with Hoosiers. The widths were 245/275 on the 17's and 245/285 on the 18's. Both sets of wheels were 8's and 10's.
We were both about a second faster around Mid Ohio. Of course he was a couple seconds faster than myself.
Not only was the car faster but it felt more precise and didn't take a double set. By that I mean, on the 17's the car would take a set in the turn and then you would feel the tires roll over and take a second set.
I know you Vinnie, and you want the best so go with the 18's. Might as well get two sets so you have a second set of race tires incase you wear a set out over a weekend.
For street tires look at the Toyo t1-S they have a slightly taller sidewall and it should give you a bit more cushion for the potholes.
Take care,
Greg

Terry Adams

I have the factory hollow spoke 18", and agree with 993RS and Greg on the handling opinion. However, 18" are very susceptible to pothole damage, especially the rears, as I learned twice. OK, I am a slow learner. Anyway, once I had to have the wheel replaced (ouch) and the other time it was repaired (phew). Each time I had the damage, I was running 32F/34R inflation. I have since settled on 34/40 rather than the spec cold inflation of 36/44.

Vinnie

Thanks guys, I knew all that sidewall couldn't have been good! :-) There's always a trade off in terms of comfort and performance :-) Pay to play!

Greg, LOL! you know me too well...I'm going to get one set and then save for the transmission! :-) I hope to see you at some DE this year!

Terry, I too bent 3 18 inch hollow spoke rims in NYC....I guess I learn slower :-P I agree with what every one has said, but potholes suck :-)

Thanks everyone, more is always is welcome!

Best regards,

dcpmark

[quote]Originally posted by Terry Adams:
<strong>Each time I had the damage, I was running 32F/34R inflation. I have since settled on 34/40 rather than the spec cold inflation of 36/44.</strong><hr></blockquote>

My tire and wheel guy told me that wheel damage on 18's happens when the tires are NOT fully inflated, i.e. not at 36/44. If true, seems like you are still running a risk of bending those rims.

E. J. - 993 Alumni

I hate to be the lone voice of dissention here, but I feel that unless you are running a full race suspension set-up, you will be hard pressed to feel the difference. Greg and his friend could tell on the race car, I doubt you could tell on a street car. Even if you could, one second is not a lot for the added expense and worry of potholes etc...

I say save some money towards the tranny and use 17s on the street and track. The wheels are cheaper and the tires are a lot cheaper. Hell, get used Hoosiers for $75 - they last almost as long.

Of course: YMMV!

E. J.

Terry Adams

"My tire and wheel guy told me that wheel damage on 18's happens when the tires are NOT fully inflated, i.e. not at 36/44. If true, seems like you are still running a risk of bending those rims."

dc pmark, I think he's right, but I do agree with some posters that a lower inflation improves handling, so I was being the compromising kind of guy my wife would tell you I am. Sometimes I start the month at 36/44 and let it drift back to 34/42 on its own.

Viken

[quote]Originally posted by dcpmark:
<strong>My tire and wheel guy told me that wheel damage on 18's happens when the tires are NOT fully inflated, i.e. not at 36/44. If true, seems like you are still running a risk of bending those rims.</strong><hr></blockquote>

I have been running pressures of as low as 26/28 with my 18's without any problems. Porsche wheels are very strong and will resist bending more than some aftermarket wheels. Those with a bending tendency are of the multi-piece variety with a spun aluminum rim half which is often too soft.

Terry Adams

So Viken, you must have the latest Valentine pothole detector installed?

Viken

[quote]Originally posted by Terry Adams:
<strong>So Viken, you must have the latest Valentine pothole detector installed?</strong><hr></blockquote>

LOL! I guess I'm just lucky as I hardly encounter a serious pothole while driving my car.

Vinnie

Thanks everyone! E.J. I'm leaning towards your train of thought, especially with my driving abilities, the 17s are the way to go here (NYC) for a street tire and the stock 18s will be used for the track! :-) Too bad the 17 FIKSE are so much lighter than the hollow spokes....anyone want to buy them? :-)

Viken, I think you're right but I'll also probably be the first one on the list to wear away their front protection bar :-)

Another side note: Any opinions on the Yoko AVS Sports (much cheaper)? Tirerack has them on special now and I think they'd be a great compromise over the Michelin Pilot Sports with some wet handling sacrifice (but then again I have AWD :-))

Jgordon

Hey, I'm just over here checking out life on your side of the fence. I'd definitely go with the 17s. I'm running 16s (Yeah, I know, boo, hiss) and I manage to find every pothole on this damn island. I'm running my POs Yokohamas, hard tires with a nice thick sidewall, and I've still stopped on occasion to take a look at the wheel after a pothole snuck up on me.

I've been out to LA, and the fact that there's no frost/thaw cycle there means that the roads are great (in my experience). My feeling is, buy a set of 18s for track, and use the 17s for real life. ESPECIALLY if you come over to this side of the river.

David '96 993

Vinnie,
If you are concidering the Yok's also look into the Toyo T1S as well. They are similarly priced. I do not currently have the Toyos on my 993, but do have them on a 4000lb BMW M5. I was quite pleased with the Toyo performance both on and off track. They are a good balance of performance, comfort and price. I found them to communicate quite well and were very predictable.

I have not tried the Yokohamas but I have heard a couple of friends comment that they were a bit noisy after spirited driving <img src="graemlins/jumper.gif" border="0" alt="[jumper]" />

Craig in Texas

I've used the AVS Sports for years on both my 993 and my Z car. I love them. They stick well, are predictable, and wear well. I've used them on the track and at autocrosses. I've heard complaints about them being more noisy, but I don't notice. Maybe I just have the stereo turned up too loud.