wanderingwheelz

I'm contemplating swapping out for my OEM 19" Sport Design wheels for 20" Champion Motorsports 20" wheels. I would appreciate any comments on the move- pro and/or con.

Will the aftermarket value of my 2012 997.2 S be harmed by putting after market wheels on it? It goes without saying the Champion wheels are of the highest quality. How will the ride quality be altered, if at all?

Would OEM wheels have to be put back on the car to have it qualify as a CPO sale? I'd prefer to not have to store the Sport Design wheels.

I'l take any offer on the Sport Design wheels, too. The OEM Michelin PS2 are in great shape no plugs or patches- the odomoter on the car only reads 900 miles. The wheels are perfect, as you'd expect.

Thanks. Dan

Suns_PSD

20" wheels significantly negatively effect a car's handling, acceleration, and braking. In my eyes that is the most important concern.

Even if you buy a top of the line forged 20" wheel that isn't particularly heavy, the Moment of Inertia still increases and needed tire flex decreases. Both are bad things.

The idea is to have equal tire sidewall distance front to back. There is a reason many very high performance automobiles run double staggered wheel set ups. Basically an 18" in the front and a 19" in the rear. As a bonus, the optical illusion where it appears the front rim is actualy larger than the rear rim (because of the smaller front sidewall) goes away and the wheels look completely equal.

And it's a Porsche so nothing but Forged wheels will do imo. I prefer BC Forged wheels personally because they are 100% custom, any offset, and width, any finish, etc...

Good Luck!

solomonschris

I just bought a 991 S that came with 20" Carrera Classic wheels. When I need to replace the tires, I will likely go with 19" wheels from HRE or one of the other quality wheels. Before doing so I will ask the advice of the many sages here. My first 911, a 1987 coupe decades ago had 16" wheels, considered a big deal at the time!

solomonschris

I really doubt that Porsche would fit a 20" wheel if it negatively affected handling, braking and acceleration....I mean to say, why on earth would they?

wanderingwheelz

If Porsche is fitting 20" on the new 991s, like they are, why would someone want to go to 19" wheel? The PASM in comfort setting should offer a plenty supple ride from all of the reviews I've read on the 991. Wouldn't be safe to assume that Porsche put the ideal OEM wheel on the car, i.e. 20"?

This gets to the crux of the issue for me.... Would a 20" wheel on a 997 go counter to what Porsche considers to be an ideal set-up?

Spokane5150

Agree. Some of the guys are using 18" wheels but mostly because tires cost a lot less. I really don't get the 20" wheels. Engineers specify and adjust spring rate and shock valving based on the stock wheels and unsprung weight. I believe when you start changing thing too much the performance will suffer. I'd stick with 19" and buy forged wheels that are a little lighter and much stronger.

Suns_PSD

They fit them because it's fashionable.

Look around and let me know of any professional race team that runs large diameter wheels and low profile tires. Formula One? 14" I believe and only that large because they have to fit serious brakes. Stock racing cars. Nope.

Large wheels are terrible for all aspects of performance.

One must realize that the weigh of any rim/ tire set up is concentrated right where the rim ends and the tire bead begins. That ring of area has thicker materials and some overlap as well. So even if you buy a low-pro rim/ tire combo that weighs the exact same amount, same outer diameter tire so no gearing change, the larger rim diameter will accelerate, stop, and turn less well much like that bicycle tire that you and your buddies use to spin in the garage as kids. Keep in mind that as speeds increase, small differences in rotating weight become very large indeed.

Furthermore, if you do track days, 18" tires have more options and cost notably less $. But mainly you will just have way more choices in tires.

Lastly, I happen to think really large rims look they belong on an Escalade in a rap video. It's all show and no go, and that's not attractive to me.

Bijan

The 991S here has 245/35 ZR 20 tires at the front, 295/30 ZR 20 tires at the rear so the wall heights are similar to the 997 19" wheels. Resulting in 1" larger diameter wheels.

Breitling

I have 20" Champion wheels. I bought the car that way. Sorry for the crappy pic but that's all I have at the moment.

Spokane5150

My son has that new Samsung Galaxy and the picture that it takes are amazing. You must have a blackberry like me. My company is switching over to I-phones. Thousands of blackberry going to i pads and i phones.

You car looks good. Obviously you didn't make the decision but I think if you have the option its better to stick with 19" wheels unless looks are what you're after.

stiles_s

Not sure you picked this up from the other replies, but I'll take a crack at answering: the overall height of the 991's 20" setup is taller than the 997's 19" setup. This gives the 991 about as much sidewall (a critical piece of the ride/handling equation) on 20s as we have on the 997 on 19s.

Going to 20s on a 997 would land you with (IMHO) absurdly short sidewalls.

TJ Elliott

To the OP, keep things in perspective. The people posting about not going to 20" are expressing their opinion and many have not run 20". The theoretical argument of unsprung weight and moment of inertia and it's effect on performance, although true, doesn't come into play when driving on the street. On the track yes it does and you can feel the difference once you develop a level of competence.

I speak from experience as I run 20" Techart's on the street and 19" OZ's with r-comps on the track. It's a matter of taste and the intended use of your car. If you like the looks of 20" wheels and the intended use is street driving then go for it.

Suns_PSD

I've ran many different size rims back to back and larger rims, even really expensive ones, really make the car feel slower everywhere.

I watched a friend lose 23 rwhp on the dyno on a Corvette when we switched from 18s to 20s. And remember that the dyno only sees the increased weight on the rear wheels, but rolling down the street you can feel both front and back and in the case of my friend's Vette, effectively doubling that 23 hp loss in the real all four wheels spinning world.

If you like the looks, then by all means get the 20s. Just don't think for a second that it's a performance improvement in any way.

On a slow car I had a few years back I had a set of OZ Ultraleggeras in 18" that I decided to send off for some clean up. In the mean time I had to mount up some 16" steelies (same OD tires) and run for a month. Imagine my disappointment when the car was notable more lively/ quick/ better turning/ stopped better w/ the freakin' steel wheels!

I also swapped from 18s to 20s on a diesel truck and promptly lost 2 mpg.

My goal is not to discourage the OP from getting exactly what he wants, but to just get the facts out there as there is a LOT of incorrect info on this topic out there.

IMO, rims on a sports car should not be bought w/ looks as the primary determining factor, actually improving performance should be number one. Could you imagine if someone sold a beautiful exhaust system that sounded great but actually lost power everywhere? For a show car, sure. Lots of people modify cars for looks in a way that actually decreases performance. For a proper sports car however...

Anyways I'll bow out of this discussion because I made my point already.

Good Luck.

solomonschris

I am learning stuff at RL all the time. My main reason to go to a smaller rim is to save tire damage from the crappy roads around DC. I just remembered that I bought the door ding/tire/wheels insurance pkg when I bought the car. Switching to aftermkt wheels probably voids the policy. The only positive thing i'vecread about larger wheels with lower profile tires is that they give quicker turn. One of my employees had 24" in wheels on his Buick (the dope dealer look don't you know) and I heard driving it was a challenge.

kosmo

this.

to me weight is less of a concern vs the potential of wheel damage, all things equal. If you like 20s get'em, just stay away from the pot holes.