General consensus on wheel sizes?

[CRCGuy]

Interested in the current views on wheel sizes. Particularly for 987 but not sure if it matters. 17 vs 18 vs 19 All other things equal, does handling noticeably improve going up? Ride quality suffer inversely?

As a former NA miata owner, the younger folk on the forums tried to stuff the largest wheels they could under the wells, but the more "seasoned" enthusiasts tended to agree that really the lower range (say 15's) work the best performance-wise.

Just wondering what the more experienced owners have to say about wheels on a Box.

CRCguy

[Lil bastard]

IMHO, the best compromise between aesthetics, ride, performance and cost is 18".

19s and 20s hurt performance and ride while costing a lot more to shoe them, for me, that's not offset by a better aesthetic. In fact, once you get to 20s, you're approaching the Donk range for these cars.

I'm sure there are others who disagree and will chime in with their opinions. That's OK and why America, and this forum, are so great!

[986Roadster]

I have 19z and Lil Bastard is 100% correct!

I used to push hard on here that 19z were the way to go. They look too
big on the car. Looking at the car from the back on an angle, the wheels
don't look good. The rear bumper is too small looking.

18z are the way to go. I've seen 18z on a Boxster and from far could barely tell that they were 18z....looked like 19z.

I will most likely go back to 18z. The overall ride is decent.

[jcb986]

I have 18's and they look great... :dance:

[Bladecutter]

Originally Posted by CRCGuy

Interested in the current views on wheel sizes. Particularly for 987 but not sure if it matters. 17 vs 18 vs 19 All other things equal, does handling noticeably improve going up? Ride quality suffer inversely?

Just wondering what the more experienced owners have to say about wheels on a Box.

CRCguy

To be perfectly honest, the only thing that is going to make a difference in the actual performance of the car is the width of the tire. The wider the tire, the larger the contact patch connecting the car to the ground, and offering feedback to the driver.

Wider tires, of course, need wider wheels.
Typically, the tire manufacturers recommends a range of wheel widths to fit their tire of a specific size and construction. And they most likely are not going to offer that same tire size in each and every wheel diameter available, otherwise they would have to make way too many molds for every tire they produce.

Also, a smaller wheel weighs less, and that takes less power and effort to change directions, accelerate, and slow it down once its spinning, which makes the car feel more responsive, and nimble.

I think the best question to ask is what are the tire sizes needed for optimal performance. The original 986 came with 205/55-16 tires in the front, and 225/50-16 in the rear as stock. The optional wheel package came with 205/50-17 up front, and 255/40-17 in the rear. I'm pretty sure everyone will agree that a 986 equipped with the optional wheel/tire package out performed the base wheel/tire setup.

So, what's the ultimate combination of tire sizes for the front and rear for superb handling, yet still retains the car's flick-ability, and driving characteristics? Once we have that, then we can probably figure out the best size wheels to mate those tires to the car.

BC.

[986FortyEight]

+1 on 18s. HOWEVER, if you are going the R-compound route, know that it cost me $1350 on 18s VS $850 on the 17s...

[CRCGuy]

Thanks! great information guys. It just occurred to me that that one of the reasons I asked is what 986roadster said. I saw a 987 last week with 19's (sport design wheel I think) and it did look a bit out of proportion for some reason but couldn't quite place it at the time. But now that you mention it, you're right, just a touch too big.

Lil bastard: thanks. Didn't even think about the increased tire costs. I don't have my box yet, but when I do, I'm fairly certain I'm gonna go through some tires

Thanks again. Keep 'em coming. But sounds like 18 is a nice compromise--keeping in mind the tire size issue, but sounds like law of diminishing returns as you go any larger.

CRCguy

[stephen wilson]

As with most things, it depends on your usage. if you're hard core about Autocross, 17's will probably be best. Will you be doing serious track days, or just spirited street driving/moderate track running? 19's should give slightly sharper steering response, but I don't know that ultimate grip goes up over 18's, which to me have great response, but I've never driven on 19" wheels.

I would suggest test driving cars with each wheel size 17-19", then decide which suites you. The OEM 17" wheels/tires are narrower, so will have less grip than the larger sizes.

Having said that, I think 18's are the best for me, though I would like try a car on 19" wheels.

Steve

P.S. Oh yeah, The highest ultimate grip will come from stuffing the widest tires/wheels possible under the fenders, without raising the ride height, which you would actually want lower, regardless of wheel diameter.

[landrovered]

It all boils down to physics. Turning is a product of tire deflection and the balance is struck between sidewall height and grip. I personally think that ultra thin sidewalls look bad and they have less ability to deflect due to the physical limit imposed by their smaller size. That being said a huge sidewall is not going to necessarily going to turn better because of the forces will not be as efficiently transfered to the wheel as with a moderate sidewall. Like I said it is a balance.

A practical example of this is modern racing tires. If tiny thin sidewalls were faster then every F1 car would be on wheels with rubber bands glued to them but they are not. Look at racing cars for the most efficient tire construction in terms of wheel size to sidewall/contact patch.

F1 rules state that the front tire must be between 305-355 mm wide with a maximum diameter of 660 mm. These are on 13" rims. The ratio of width to diameter is roughly 1 to 2 with the rim being roughly equal to the width. In short the tires are square. The sidewall height of the F1 tires is roughly equal in proportion to that of a "50" street tire.

So the most badass cars in the world are running on schweet 330/50/13s, how is that going to hang on the street?