Why go from 17” wheels to 18”?

[cantdrv55]

Hi all. Just wondering what the benefits are from 17 to 18 inch wheels for an S other than looks. I found a set of Porsche 18s wheels for $600. No tires, just wheels. Is there a performance benefit and is it worth the extra cost of wheels and bigger set of tires? The tires on my 17s need to be replaced anyway so nows the best time to w the change. Thanks.

[Anker]

The drawbacks are a harsher ride and more expensive tires.

[DoninDel]

Originally Posted by Anker

The drawbacks are a harsher ride and more expensive tires.

And, usually, the typical compound used in 18" tires wears faster than the typical 17" tire compound, as 18s usually have a higher performance rating.

[JayG]

Originally Posted by DoninDel

And, usually, the typical compound used in 18" tires wears faster than the typical 17" tire compound, as 18s usually have a higher performance rating.

Really???

Performance rating has nothing to do with tire diameter.
I would think the compound in a given tire model would be the same regardless of size.

[Boxstard]

Originally Posted by Anker

The drawbacks are a harsher ride and more expensive tires.

And weight... Stock to stock 17" is lighter with tire mounted.

[Ciao]

18" will compensate some from lowering the P car to status quo

[azlvr]

Originally Posted by cantdrv55

Hi all. Just wondering what the benefits are from 17 to 18 inch wheels for an S other than looks. I found a set of Porsche 18s wheels for $600. No tires, just wheels. Is there a performance benefit and is it worth the extra cost of wheels and bigger set of tires? The tires on my 17s need to be replaced anyway so nows the best time to w the change. Thanks.

Better looks.

[kk2002s]

Doesn't the S need the 18s because of the larger front brake caliper or do 17s have enough clearance?

I have 18s but I would think that 17s would handle better and tires would be a bit cheaper

[Jgkram]

Looks mostly. The 18's fill the wheel well more than the 17's. I have a set of 18's I run normally and 17's I use for autocross. I can't tell a huge difference in the ride quality but I'm sure there is a little bit as the 17's put more space between you and the road.

[RedTele58]

Originally Posted by kk2002s

Doesn't the S need the 18s because of the larger front brake caliper or do 17s have enough clearance?

I have 18s but I would think that 17s would handle better and tires would be a bit cheaper

S models are fine (and were standard wheel) with 17's. It's 16's that don't clear the calipers.

[Blackcloud]

But with 18’s you can get Bridgestone RE-71’s on! Not on 17’s.

[cantdrv55]

Originally Posted by Blackcloud

But with 18’s you can get Bridgestone RE-71’s on! Not on 17’s.

Serious question. Is that a good thing? I thought most prefer Michelins.

[JayG]

Originally Posted by Blackcloud

But with 18’s you can get Bridgestone RE-71’s on! Not on 17’s.

what you talking bout Willis??

Re-71's and lot of other trackable tires come in correct 17" sizes. I and many others have been running RE-71's in 255/40-17 and 225/45-17 for years

17's fit a S no problem
17's are lower cost

[Anker]

Originally Posted by Blackcloud

But with 18’s you can get Bridgestone RE-71’s on! Not on 17’s.

Yes, you can. Just go with the 225/45-17 instead of the 205/50-17. its 2 cm wider, but fits the rims and doesn't rub. As a bonus you get slightly better grip cornering because of the bigger contact area.

(Edited. the width to sidewall ratios were wrong in the original)

[lskolnick]

Originally Posted by RedTele58

S models are fine (and were standard wheel) with 17's. It's 16's that don't clear the calipers.

16's with the correct offset would have no problem clearing the S calipers. The problem is nobody makes them.

[cantdrv55]

My favorite tire place, Costco, doesn’t carry the RE-71s for the front! Too bad as Bridgestone are on sale.

[PaulE]

I’ve got a set of 17” Boxster II wheels I bought and the 18” Lt Alloy Carrera wheels the car came with. With OEM Pilot Sport N3 tires mounted the front 17 and 18”s weigh the same. The 18 inch rears weigh less than 2 lbs more than the 17’s. Every lb counts with unsprung weight but gaining an inch diameter in rim is offset by losing a half inch of rubber sidewall on both sides of the tire. For street driving there is no difference but an extra half inch of sidewall to protect your rims from potholes is nice. On the 18’s I just replaced the tires with Pilot Sport 4S tires bought at Costco and mounted by them on my refinished wheels. They do a great job at Costco and with the deal they had on Michelin’s last June, similar to their current Bridgestone deal, I was out the door for less than just buying the tires from Tire Rack. Costco is the only tire place I’ve seen that gives you nitrogen for no charge and religiously uses a torque wrench for the final tightening. YMMV.

[Boxstard]

Originally Posted by PaulE

I’ve got a set of 17” Boxster II wheels I bought and the 18” Lt Alloy Carrera wheels the car came with. With OEM Pilot Sport N3 tires mounted the front 17 and 18”s weigh the same. The 18 inch rears weigh less than 2 lbs more than the 17’s. Every lb counts with unsprung weight but gaining an inch diameter in rim is offset by losing a half inch of rubber sidewall on both sides of the tire. For street driving there is no difference but an extra half inch of sidewall to protect your rims from potholes is nice. On the 18’s I just replaced the tires with Pilot Sport 4S tires bought at Costco and mounted by them on my refinished wheels. They do a great job at Costco and with the deal they had on Michelin’s last June, similar to their current Bridgestone deal, I was out the door for less than just buying the tires from Tire Rack. Costco is the only tire place I’ve seen that gives you nitrogen for no charge and religiously uses a torque wrench for the final tightening. YMMV.

Okay, I stand corrected... 18" light Carrera wheel is well, light as 17". But for most cases going bigger results in heavier.

Anyway factory does not recommend 18" wheels for 1997, keeping my options plain and simple.....

[JayG]

If you are buying Bridgestione tires, get the best price you can from COSTCO, or online and then go to a Firestone store. They will match the price and if you use a Firestone credit card, you get an additional 5% off.

Another place for a deal is Summit Racing. They will beat any verifiable priced. IIRC, they often have free shipping as well. I have played that game with them several times on brake pads and otherr parts. My last set of Nt-01's too came from them. I found my tire size mispriced on Amazon and Summit beat it by a buck and I got them in 2 days