997 turbo rims fit 996 turbo?
#48
01-20-2011, 12:07 AM
After reading all the threads I have opted to go with the following tires sizes. It shows the least number of revs delta (4) resulting in a .0453% difference.
225/40/19
305/30/19
I didn't want to push the envelope on the width of the 315. These actually fill out the wheel well very nicely. I am also running 7mm spacers on the front and 14mm on the rear. Pics to follow tomorrow in the daylight.
I found this website very useful since you can input multiple tires sizes for comparison including OD, sidewall, revs per mile, tread width, everything. Hopefully this helps with the question or issues of tire size discrepancies.
http://www.1010tires.com/TireSizeCalculator.asp
225/40/19
305/30/19
I didn't want to push the envelope on the width of the 315. These actually fill out the wheel well very nicely. I am also running 7mm spacers on the front and 14mm on the rear. Pics to follow tomorrow in the daylight.
I found this website very useful since you can input multiple tires sizes for comparison including OD, sidewall, revs per mile, tread width, everything. Hopefully this helps with the question or issues of tire size discrepancies.
http://www.1010tires.com/TireSizeCalculator.asp
Last edited by TheCarDudes; 01-20-2011 at 12:18 AM.
#49
01-20-2011, 09:10 AM
After reading all the threads I have opted to go with the following tires sizes. It shows the least number of revs delta (4) resulting in a .0453% difference.
225/40/19
305/30/19
I didn't want to push the envelope on the width of the 315. These actually fill out the wheel well very nicely. I am also running 7mm spacers on the front and 14mm on the rear. Pics to follow tomorrow in the daylight.
I found this website very useful since you can input multiple tires sizes for comparison including OD, sidewall, revs per mile, tread width, everything. Hopefully this helps with the question or issues of tire size discrepancies.
http://www.1010tires.com/TireSizeCalculator.asp
225/40/19
305/30/19
I didn't want to push the envelope on the width of the 315. These actually fill out the wheel well very nicely. I am also running 7mm spacers on the front and 14mm on the rear. Pics to follow tomorrow in the daylight.
I found this website very useful since you can input multiple tires sizes for comparison including OD, sidewall, revs per mile, tread width, everything. Hopefully this helps with the question or issues of tire size discrepancies.
http://www.1010tires.com/TireSizeCalculator.asp
I'd advise you to contact Porsche about this, although I'm afraid they are always not that much help when it comes to modifications, even if just with newer model equipment on old cars.
#50
01-20-2011, 03:55 PM
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#51
01-20-2011, 07:25 PM
I'm not sure I follow. Are we not talking about a 19'' rim here? Also, 315/30/18 says 25.5'' tall, not 26.3'' tall like TheCarDudes is suggesting he'll get. The concern is rubbing here, not ratios or overheating the diff from improper ratios.
#52
01-22-2011, 06:05 PM
Update
After reconsidering all the info here I opted to go to the following combination:
235/35/19
315/25/19
The other setup I had was too tall and looked terrible on the car. I only chose that combo mainly because the revs per mile and OD was the closest front to back. I knew I would be playing with fire on the rubbing aspect. Furthermore, the new set up looks 1000% better.
Thanks to everyone for posting the info.
Here are the pics:
235/35/19
315/25/19
The other setup I had was too tall and looked terrible on the car. I only chose that combo mainly because the revs per mile and OD was the closest front to back. I knew I would be playing with fire on the rubbing aspect. Furthermore, the new set up looks 1000% better.
Thanks to everyone for posting the info.
Here are the pics:
#53
01-22-2011, 06:39 PM
After reconsidering all the info here I opted to go to the following combination:
235/35/19
315/25/19
The other setup I had was too tall and looked terrible on the car. I only chose that combo mainly because the revs per mile and OD was the closest front to back. I knew I would be playing with fire on the rubbing aspect. Furthermore, the new set up looks 1000% better.
Thanks to everyone for posting the info.
Here are the pics:
235/35/19
315/25/19
The other setup I had was too tall and looked terrible on the car. I only chose that combo mainly because the revs per mile and OD was the closest front to back. I knew I would be playing with fire on the rubbing aspect. Furthermore, the new set up looks 1000% better.
Thanks to everyone for posting the info.
Here are the pics:
#54
01-23-2011, 09:02 AM
I will keep you up to date. I have hit just a few turns here and there but have not had a chance to do it safely where the PSM might go off. Too much traffic around. I'll let you know if and when, what speed, conditions, etc.
#55
01-23-2011, 11:35 AM
everyone is right--this question has been addressed numerous times.
When I first went to 19" HREs for my 2002 996TT X-50 there were, as everyone notes, no problems with the rims at all. The wheels and tires I purchased were meant for a 997TT, there were no problems with the front tires but the factory specified rears for the 997TT are or were 305/30/19s--so a higher side-wall aspect ratio and the narrower rear track of the 996TT vs. the 997TT created an issue with the rear tire size. The 996TT with 19" rims called for 315/25/19 (as I recall). The 305s with the 30 aspect ratio rubbed, bottomed out when cornering on anything but the flattest, smoothest of roads--difficult to find. Rubbing tires are not something I find acceptable, enjoyable, or livable in any vehicle but especially with the cornering speeds, adhesion limits, and the generally intense capabilities of these wonderful machines. The rear wheel flairs would have to be modified by someone you really trusted to accommodate tires with a 30 series aspect ratio. While I have folks I trust to do anything to my Turbo it did not seem worthwhile to seriously consider that degree of modification to the rear body panels since there was a huge and immediate market for the 305/30/ZR19 PS2s. I simply bought a new set of 315/25/ZR19s PS2s for the rear wheels. I've had absolutely no problem with this arrangement for the past 8,000 miles.
I don't know about 255/30-19s as a valid option for front tire size--I have not heard of anyone doing that. Which means nothing since there are a great many things I have not heard of. It intuitively feels like there could be serious issues with turn-in. But what the heck do I know about intuition. My front tires are (I think) standard for a 997TT--they are 235/35/ZR19"s and of course the rear tire sizes are dictated by the narrower rear track of my 996TT relative to the 997TT. With absolutely no spacing the 305, 30, ZR19"s were sitting right against the inner fenders. The result being the 315/25/ZR19s. With the lower aspect ratio there's no rubbing whatsoever and there's a relatively massive contact patch on the tarmac. So even with a significantly modified engine it just puts the power to the road and I don't have to watch that painful process of spinning, PS2s $ floating off as smoke into the atmosphere. It hooks up instantly, maintains contact and goes, and just keeps going.
I don't know about 255/30-19s as a valid option for front tire size--I have not heard of anyone doing that. Which means nothing since there are a great many things I have not heard of. It intuitively feels like there could be serious issues with turn-in. But what the heck do I know about intuition. My front tires are (I think) standard for a 997TT--they are 235/35/ZR19"s and of course the rear tire sizes are dictated by the narrower rear track of my 996TT relative to the 997TT. With absolutely no spacing the 305, 30, ZR19"s were sitting right against the inner fenders. The result being the 315/25/ZR19s. With the lower aspect ratio there's no rubbing whatsoever and there's a relatively massive contact patch on the tarmac. So even with a significantly modified engine it just puts the power to the road and I don't have to watch that painful process of spinning, PS2s $ floating off as smoke into the atmosphere. It hooks up instantly, maintains contact and goes, and just keeps going.
Last edited by rlj996tt650gt; 01-23-2011 at 02:35 PM.
#58
02-27-2011, 03:46 PM
everyone is right--this question has been addressed numerous times.
When I first went to 19" HREs for my 2002 996TT X-50 there were, as everyone notes, no problems with the rims at all. The wheels and tires I purchased were meant for a 997TT, there were no problems with the front tires but the factory specified rears for the 997TT are or were 305/30/19s--so a higher side-wall aspect ratio and the narrower rear track of the 996TT vs. the 997TT created an issue with the rear tire size. The 996TT with 19" rims called for 315/25/19 (as I recall). The 305s with the 30 aspect ratio rubbed, bottomed out when cornering on anything but the flattest, smoothest of roads--difficult to find. Rubbing tires are not something I find acceptable, enjoyable, or livable in any vehicle but especially with the cornering speeds, adhesion limits, and the generally intense capabilities of these wonderful machines. The rear wheel flairs would have to be modified by someone you really trusted to accommodate tires with a 30 series aspect ratio. While I have folks I trust to do anything to my Turbo it did not seem worthwhile to seriously consider that degree of modification to the rear body panels since there was a huge and immediate market for the 305/30/ZR19 PS2s. I simply bought a new set of 315/25/ZR19s PS2s for the rear wheels. I've had absolutely no problem with this arrangement for the past 8,000 miles.
I don't know about 255/30-19s as a valid option for front tire size--I have not heard of anyone doing that. Which means nothing since there are a great many things I have not heard of. It intuitively feels like there could be serious issues with turn-in. But what the heck do I know about intuition. My front tires are (I think) standard for a 997TT--they are 235/35/ZR19"s and of course the rear tire sizes are dictated by the narrower rear track of my 996TT relative to the 997TT. With absolutely no spacing the 305, 30, ZR19"s were sitting right against the inner fenders. The result being the 315/25/ZR19s. With the lower aspect ratio there's no rubbing whatsoever and there's a relatively massive contact patch on the tarmac. So even with a significantly modified engine it just puts the power to the road and I don't have to watch that painful process of spinning, PS2s $ floating off as smoke into the atmosphere. It hooks up instantly, maintains contact and goes, and just keeps going.
When I first went to 19" HREs for my 2002 996TT X-50 there were, as everyone notes, no problems with the rims at all. The wheels and tires I purchased were meant for a 997TT, there were no problems with the front tires but the factory specified rears for the 997TT are or were 305/30/19s--so a higher side-wall aspect ratio and the narrower rear track of the 996TT vs. the 997TT created an issue with the rear tire size. The 996TT with 19" rims called for 315/25/19 (as I recall). The 305s with the 30 aspect ratio rubbed, bottomed out when cornering on anything but the flattest, smoothest of roads--difficult to find. Rubbing tires are not something I find acceptable, enjoyable, or livable in any vehicle but especially with the cornering speeds, adhesion limits, and the generally intense capabilities of these wonderful machines. The rear wheel flairs would have to be modified by someone you really trusted to accommodate tires with a 30 series aspect ratio. While I have folks I trust to do anything to my Turbo it did not seem worthwhile to seriously consider that degree of modification to the rear body panels since there was a huge and immediate market for the 305/30/ZR19 PS2s. I simply bought a new set of 315/25/ZR19s PS2s for the rear wheels. I've had absolutely no problem with this arrangement for the past 8,000 miles.
I don't know about 255/30-19s as a valid option for front tire size--I have not heard of anyone doing that. Which means nothing since there are a great many things I have not heard of. It intuitively feels like there could be serious issues with turn-in. But what the heck do I know about intuition. My front tires are (I think) standard for a 997TT--they are 235/35/ZR19"s and of course the rear tire sizes are dictated by the narrower rear track of my 996TT relative to the 997TT. With absolutely no spacing the 305, 30, ZR19"s were sitting right against the inner fenders. The result being the 315/25/ZR19s. With the lower aspect ratio there's no rubbing whatsoever and there's a relatively massive contact patch on the tarmac. So even with a significantly modified engine it just puts the power to the road and I don't have to watch that painful process of spinning, PS2s $ floating off as smoke into the atmosphere. It hooks up instantly, maintains contact and goes, and just keeps going.
rlj996tt650gt, what spacers are you running? I am about to mount the exact tire sizes on my 04 996TT!
#59
09-03-2011, 11:20 AM
Is anyone here running 295/30/19 and 225/40/19 with 997tt wheels on thier 996tt and not having any issues? Are you using spacers? I've seen at least two reports, including one in this thread, of 295/30/19 causing rubbing in the rear b/c they are too tall.
