Benefit of 19s vs. 18s
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I've got to agree with Hamann on this one. I have been looking at wheels for several weeks now and I am convinced that anything other than an 18 on a Gt2 will have a negative effect on my handling and cornering feel. I really believe that Porsche put 18's on the car after years of testing and the 18 yielded the best results, although I've had many wheel vendors attempting to convince me otherwise. I'm looking at Champions which after some research are some of the lightest wheels available other than Dynamags.
It really does boil down to what is important to you, I am no expert but there must be a change in the suspension characteristics when you change wheel diameter. There really isn't any other true reason to change to a 19 absent aesthetics, because an 18 will usually weigh less that a comparable 19. Whatever makes you happy is usually the best answer since there is no wrong or right depending on what you are trying to accomplish.
It really does boil down to what is important to you, I am no expert but there must be a change in the suspension characteristics when you change wheel diameter. There really isn't any other true reason to change to a 19 absent aesthetics, because an 18 will usually weigh less that a comparable 19. Whatever makes you happy is usually the best answer since there is no wrong or right depending on what you are trying to accomplish.
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Joe Weinstein's analysis is spot on. He is also one of the most knowledgable guys on this board when it comes to suspension and race tuning.
Heavychevy, with all due respect, you should probably pay more attention to what Joe is saying rather than dismiss his analysis as only having to do with ride quality. He has a hell of a lot of experience, probably more than you and me combined, several times over.
The sidewall stiffness or "spring rate" of the sidewall has everything to do with handling, not just ride quality. It determines how progressively or suddenly the tires break away, absorb bumps (especially under lateral load), etc. Suspension tuning can only compensate so much.
In addition, on the 996 it's pretty much impossible to maintain the exact same rolling diameter on a 19" wheel as an 18" wheel. Porsche went to 19" on the 997, but one must realize that the overall rolling diameter on a 997 chassis is LARGER than a 996, and all the systems are calibrated for such. The sidewall aspect ratio on a 997 wheel is also larger on the 996, they run 30 or 35 series in the rear, as opposed to a 25 on a 996. So more sidewall on a 997, even at the same diameter.
Maybe I tend to drive hard, but for me, having personally experienced 19's on a 996 Turbo, I can safely say that I do notice the difference in handling and breakaway characteristics, and no way in hell I would ever run 19's on a 996 chassis car.
You also forgot to mention that you cannot find Porsche approved N-spec tires in 19" for the 996 fitment. This alone also makes a difference because the N tires are specifically engineered for Porsche, including the tire compound, sidewall stiffness, and carcass structure.
This is not to say that a thinner sidewall 19" tire couldn't be engineered to compensate for the difference in sidewall stiffness, etc. but the fact of the matter is, there aren't any. To me running a 19" wheel on a 996 is for pure bling, and I don't claim to be the best driver on the board, but I can definitely feel the difference. Try running 19's on a GT3 or GT2, you would feel the difference even more.
To the comment as to Porsche not designing these cars hard out of the box, my response is you should have bought a GT3. Turbos were really not meant to be track oriented out of the box, and you probably knew that when you bought the car but you didn't want to spring for the extra $$$ and buy a GT2
Some of the arguments stated on this thread by others is just pure ignorance. It's amazing how clueless some people are about their cars.
Heavychevy, with all due respect, you should probably pay more attention to what Joe is saying rather than dismiss his analysis as only having to do with ride quality. He has a hell of a lot of experience, probably more than you and me combined, several times over.
The sidewall stiffness or "spring rate" of the sidewall has everything to do with handling, not just ride quality. It determines how progressively or suddenly the tires break away, absorb bumps (especially under lateral load), etc. Suspension tuning can only compensate so much.
In addition, on the 996 it's pretty much impossible to maintain the exact same rolling diameter on a 19" wheel as an 18" wheel. Porsche went to 19" on the 997, but one must realize that the overall rolling diameter on a 997 chassis is LARGER than a 996, and all the systems are calibrated for such. The sidewall aspect ratio on a 997 wheel is also larger on the 996, they run 30 or 35 series in the rear, as opposed to a 25 on a 996. So more sidewall on a 997, even at the same diameter.
Maybe I tend to drive hard, but for me, having personally experienced 19's on a 996 Turbo, I can safely say that I do notice the difference in handling and breakaway characteristics, and no way in hell I would ever run 19's on a 996 chassis car.
You also forgot to mention that you cannot find Porsche approved N-spec tires in 19" for the 996 fitment. This alone also makes a difference because the N tires are specifically engineered for Porsche, including the tire compound, sidewall stiffness, and carcass structure.
This is not to say that a thinner sidewall 19" tire couldn't be engineered to compensate for the difference in sidewall stiffness, etc. but the fact of the matter is, there aren't any. To me running a 19" wheel on a 996 is for pure bling, and I don't claim to be the best driver on the board, but I can definitely feel the difference. Try running 19's on a GT3 or GT2, you would feel the difference even more.
To the comment as to Porsche not designing these cars hard out of the box, my response is you should have bought a GT3. Turbos were really not meant to be track oriented out of the box, and you probably knew that when you bought the car but you didn't want to spring for the extra $$$ and buy a GT2
Some of the arguments stated on this thread by others is just pure ignorance. It's amazing how clueless some people are about their cars.
I'm not dismissing anything, first of all I said I completely agreed with his post, but the fact is that the first part of it had nothing to do with the performance aspect and was more relative to comfort and risk when it comes to cracks and bends.
As far as the suspension shock being transfered to the chassy, that can be affected by as much as a simple change in tires on 18 inch wheel. Same goes for changing the springs, rates, ride height and adding coilovers. If you are a keep it stock type of guy and it works for you then great, but it's not what prefferable for everyone.
And since we are talking about stock, break away isnt all that common on and AWD car that understeers as much as the 996 TT does, so maybe some stiffness would actually help there. Porsche designed the car to be suitable to large quantities of people and I bet they went through several different suspension changes in coming to one that works. This does not mean it's the only one that works, and that the car will fail with modifications done to the suspension. The car can withstand more aggressive settings and do just fine, this has been shown time and time again.
As to what people decide to do with their cars, leave that up to them, most people that add 19's dont do so for driving hard, it's for normal street driving which will STILL have LESS impact than track driving on the N rated 18 inch wheels. The application of the wheels has as much to do as the impact on the car. Furthermore I know many that will run a 19 inch wheel on the street and 18's on the track, there is no damage being done.
Porsche has a reputation for well built cars, and they know that people all over the world track everything that comes out of there, even Cayennes. A Turbo makes a fun and safe car to put on the track. Everyone doesnt not want or need to have spent and extra 30-60k on a GT2 or wanted a GT3. As far as I can see the Porsche tuning industry has tons of engineers too and they seem to know what they are doing some of which having worked for Porsche themselves. So if they find a way to improve the handling of a car within the realm and abilities of the car, then who are you or who am I to question them unless I can prove that they dont know what their doing. Several tuners here racing every weekend, some professionally and their shop cars have similar mods to what many of us are driving on the street and track.
The fact remains that people that are adding 19's are likely not doing so for performance reasons. And if they are performance concious, they'll buy lightweight 19's which you really wont feel much difference other than a slightly bumpier ride. It's good that people know what is going on with the car when they make mods to it, but there has been nothing said here that is significant enough to make a overhaul of people ditching their wheels, it's the same stuff everybody has heard already.
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I've got to agree with Hamann on this one. I have been looking at wheels for several weeks now and I am convinced that anything other than an 18 on a Gt2 will have a negative effect on my handling and cornering feel. I really believe that Porsche put 18's on the car after years of testing and the 18 yielded the best results, although I've had many wheel vendors attempting to convince me otherwise. I'm looking at Champions which after some research are some of the lightest wheels available other than Dynamags.
It really does boil down to what is important to you, I am no expert but there must be a change in the suspension characteristics when you change wheel diameter. There really isn't any other true reason to change to a 19 absent aesthetics, because an 18 will usually weigh less that a comparable 19. Whatever makes you happy is usually the best answer since there is no wrong or right depending on what you are trying to accomplish.
It really does boil down to what is important to you, I am no expert but there must be a change in the suspension characteristics when you change wheel diameter. There really isn't any other true reason to change to a 19 absent aesthetics, because an 18 will usually weigh less that a comparable 19. Whatever makes you happy is usually the best answer since there is no wrong or right depending on what you are trying to accomplish.
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Yes, but find a race car running 19's, despite the plethora of so-called engineers out there in the race/aftermarket industry. RSRs and Cups still use 18's. There is no fuking tire selection for 19's.
Admit it. 19's are useless except for bling. Period.
Admit it. 19's are useless except for bling. Period.
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Everything that goes on the track isnt neccessary for the street. PERIOD.
19's are useless if you are looking for a performance increase. But they are not so DRAMTICALLY DETRIMENTAL as some people in here act like they are.
There is a small difference in driving characteristics, but unless you are driving at the limit, like BOTH Joe and I said, it wont make much difference. PERIOD.
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Find me a street 996 Turbo that drives in LEMANS or ALMS. No one said it's the preffered method so that's not even relevant.
Everything that goes on the track isnt neccessary for the street. PERIOD.
19's are useless if you are looking for a performance increase. But they are not so DRAMTICALLY DETRIMENTAL as some people in here act like they are.
There is a small difference in driving characteristics, but unless you are driving at the limit, like BOTH Joe and I said, it wont make much difference. PERIOD.
Everything that goes on the track isnt neccessary for the street. PERIOD.
19's are useless if you are looking for a performance increase. But they are not so DRAMTICALLY DETRIMENTAL as some people in here act like they are.
There is a small difference in driving characteristics, but unless you are driving at the limit, like BOTH Joe and I said, it wont make much difference. PERIOD.
I can feel the difference most of the time, not just at the limit.
It's all a matter of perception and opinion. In my opinion, 19's suck. Maybe not for YOUR turbo, but for my 996 GT2 and GT3, they do detract from the performance. And if you're gonna buy a GT-series car, which is generally bought for PERFORMANCE, then it's just stupid to run +1's or 2's. But since you have a Turbo, I guess 19's are no big deal.
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As said in my FIRST post...19 for show, 18 for go. No denying this....but if they work for bling then they are not useless.
BTW I went (and paid) to go to CU. Like this has anything to do with the thread. Personal attacks albeit passive aggressive simply show your maturity. Enjoy your day
BTW I went (and paid) to go to CU. Like this has anything to do with the thread. Personal attacks albeit passive aggressive simply show your maturity. Enjoy your day
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We'll have to agree to disagree on this one.
I can feel the difference most of the time, not just at the limit.
It's all a matter of perception and opinion. In my opinion, 19's suck. Maybe not for YOUR turbo, but for my 996 GT2 and GT3, they do detract from the performance. And if you're gonna buy a GT-series car, which is generally bought for PERFORMANCE, then it's just stupid to run +1's or 2's. But since you have a Turbo, I guess 19's are no big deal.
I can feel the difference most of the time, not just at the limit.
It's all a matter of perception and opinion. In my opinion, 19's suck. Maybe not for YOUR turbo, but for my 996 GT2 and GT3, they do detract from the performance. And if you're gonna buy a GT-series car, which is generally bought for PERFORMANCE, then it's just stupid to run +1's or 2's. But since you have a Turbo, I guess 19's are no big deal.
And I bet my Turbo would run circles around your GT2 and 3, since you like stock and all.
(even with 19's)
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Leave a car stock? Why the hell would anyone do that?!