Tire Upsize
The following 2 users liked this post by markmark26:
NSXavier (11-03-2021),
Robocop305 (09-13-2022)
#17
Rennlist Member
I will need some new tires in the near future and I think I'm on board with this tire upsize idea. Doing my research now. I have 19x12 &19x8.5 (OEM 997.1 GT2 wheels). It looks like most of you with 255s have 9" wide wheels. What do you guys think about the 255s on 8.5" fronts? I will be lowered on Eibach's soon.
#18
Rennlist Member
Thread Starter
I will need some new tires in the near future and I think I'm on board with this tire upsize idea. Doing my research now. I have 19x12 &19x8.5 (OEM 997.1 GT2 wheels). It looks like most of you with 255s have 9" wide wheels. What do you guys think about the 255s on 8.5" fronts? I will be lowered on Eibach's soon.
”By the book” a 8.5 with a 255 tire won’t feel as sharp as when it’s mounted on a 9, 9.5 or 10” wheel because of sidewall flex. But honestly don’t think it’ll be anything I will be able to noticeably feel.
255 front and 325 back is definitely the way to go for me. Both aesthetically and performance wise.
Last edited by NSXavier; 02-18-2022 at 10:28 AM.
The following users liked this post:
mfm3 (02-18-2022)
#19
Rennlist Member
They work. I literally just got done mounting and balancing 255/35/19 PS4S tires on 8.5” BBS LM’s an hour ago. Michelin’s rim width range is 8.5”-10” on 255 series tires. There is a very very tiny bit of overhang mounting them on a 8.5” wheel when compared to a 9”, but it still squares up nicely.
”By the book” a 8.5 with a 255 tire won’t feel as sharp as when it’s mounted on a 9, 9.5 or 10” wheel because of sidewall flex. But honestly don’t think it’ll be anything I will be able to noticeably feel.
255 front and 325 back is definitely the way to go for me. Both aesthetically and performance wise.
”By the book” a 8.5 with a 255 tire won’t feel as sharp as when it’s mounted on a 9, 9.5 or 10” wheel because of sidewall flex. But honestly don’t think it’ll be anything I will be able to noticeably feel.
255 front and 325 back is definitely the way to go for me. Both aesthetically and performance wise.
Any additional insight after running the 255/325 setup is greatly appreciated. Cheers
Last edited by kasperberry; 09-07-2022 at 05:01 PM.
#20
Rennlist Member
Thread Starter
Hey NSX, love the build. I've got a set of the same spec LMs (DSilver / polished lip) coming for my 997.1tt. lowered on Bilstein coils. Curious if you had any rubbing issues up front with the 255. If you could share your FTG and Camber specs (I'm sitting at -1.26F & -1.76R) it would be greatly appreciated. I definitely want to go 325 in the rear and would prefer to do the 255 but would like to avoid rubbing. Would consider the 245/315 or 245/325 if you were rubbing fender or radiator hose, or had to do any body/fender work to avoid rubbing.
Any additional insight after running the 255/325 setup is greatly appreciated. Cheers
Any additional insight after running the 255/325 setup is greatly appreciated. Cheers
here is the printout from the alignment I did last weekend.
The following users liked this post:
Rig.Stunts (09-07-2022)
#21
Rennlist Member
Thanks! No rubbing whatsoever when the car was on H&R springs and PASM. No rubbing now on OHLINS coilovers. Didn’t have to do any body mods to make it work. There’s actually plenty more room up front for a wider wheel and fatter tire.
here is the printout from the alignment I did last weekend.
here is the printout from the alignment I did last weekend.
#22
I found this thread:
https://rennlist.com/forums/997-turb...-question.html
and this quote:
I agree with @cstyles and I’d like to know if anyone has successfully run a
FRONT: 255/35/19
REAR: 325/30/19
combination tire. My new 19x9 & 19x12 wheels are arriving and I’d like to try get the tire sizes right the first time.
https://rennlist.com/forums/997-turb...-question.html
and this quote:
I agree with @cstyles and I’d like to know if anyone has successfully run a
FRONT: 255/35/19
REAR: 325/30/19
combination tire. My new 19x9 & 19x12 wheels are arriving and I’d like to try get the tire sizes right the first time.
Plus, and mainly, 245s on a 9in wheel will sit just perfect with just enough tire-stretch to maintain a responsive steering. However, DO NOT overlook the offset on that wheel!!! I'm running 9" up front and 12" at the back, with +35mm all around, with about an inch drop (or a tad less), some decent camber but aimed at street driving so nothing too crazy, and under no-circumstance do I have rubbing, even under high load cornering on the track... but you do get tons of burned rubber on the door panels.
So since mechanically there aren't much advantage to run 255s over 245s, then the only possible other advantage would be contact patch (ever so slightly) and if you want to increase grip, there's many other things to do before trying to add 10mm of tire width. (DSC controller, GT2 rear sway bar, proper alignment, proper tire pressure, etc...
Good luck!
#23
Rennlist Member
Many people did... it requires some digging into 6SpeedOnline as well as on here, but in short, yes there's the liner issue, but mostly there's a radiator bracket behind it that you have to remove and fiddle with the radiator itself to get it out of the way...
Plus, and mainly, 245s on a 9in wheel will sit just perfect with just enough tire-stretch to maintain a responsive steering. However, DO NOT overlook the offset on that wheel!!! I'm running 9" up front and 12" at the back, with +35mm all around, with about an inch drop (or a tad less), some decent camber but aimed at street driving so nothing too crazy, and under no-circumstance do I have rubbing, even under high load cornering on the track... but you do get tons of burned rubber on the door panels.
So since mechanically there aren't much advantage to run 255s over 245s, then the only possible other advantage would be contact patch (ever so slightly) and if you want to increase grip, there's many other things to do before trying to add 10mm of tire width. (DSC controller, GT2 rear sway bar, proper alignment, proper tire pressure, etc...
Good luck!
Plus, and mainly, 245s on a 9in wheel will sit just perfect with just enough tire-stretch to maintain a responsive steering. However, DO NOT overlook the offset on that wheel!!! I'm running 9" up front and 12" at the back, with +35mm all around, with about an inch drop (or a tad less), some decent camber but aimed at street driving so nothing too crazy, and under no-circumstance do I have rubbing, even under high load cornering on the track... but you do get tons of burned rubber on the door panels.
So since mechanically there aren't much advantage to run 255s over 245s, then the only possible other advantage would be contact patch (ever so slightly) and if you want to increase grip, there's many other things to do before trying to add 10mm of tire width. (DSC controller, GT2 rear sway bar, proper alignment, proper tire pressure, etc...
Good luck!
Last edited by kasperberry; 09-12-2022 at 04:57 PM.
#24
i only have TechArt springs on stock PASM shocks, so we tried minimizing camber as much as possible but you’re limited with stock top plates and suspension controls. The car isn’t twitchy at all, super stable even above 270 kph, but the steering is much more responsive and better balanced with the GT2 rear sway bar (only about $575 at the dealer) and the toe settings of the GT3RS! It completely changed the car where you can very easily overpower the rear end out on highway on-ramps and increase exit speed!
#25
Rennlist Member
Anyone can help me with trying to figure out if these will fit? They are ADV1 model ADV5.0 Track Function (what a name...)
Did some quick math and it seems like the specs are:
F: 20x9.5 ~ET44-46
R: 20x12 ~ET37-39
Did some quick math and it seems like the specs are:
F: 20x9.5 ~ET44-46
R: 20x12 ~ET37-39
Last edited by ipop07; 09-12-2022 at 11:34 PM.
#26
Rennlist Member
my pleasure, that’s exactly what I run and honestly, for a daily, it’s the right amount of comfort, handling, wet performance and look.. I used to run RE-71R and although they were much better in terms of handling temperature, they were way too noisy for a daily… not sure if it’ll work, but I’ll try to post a picture to get you an idea of stance (in terms of alignment, I went with the GT3RS-isshh specs…).
i only have TechArt springs on stock PASM shocks, so we tried minimizing camber as much as possible but you’re limited with stock top plates and suspension controls. The car isn’t twitchy at all, super stable even above 270 kph, but the steering is much more responsive and better balanced with the GT2 rear sway bar (only about $575 at the dealer) and the toe settings of the GT3RS! It completely changed the car where you can very easily overpower the rear end out on highway on-ramps and increase exit speed!
i only have TechArt springs on stock PASM shocks, so we tried minimizing camber as much as possible but you’re limited with stock top plates and suspension controls. The car isn’t twitchy at all, super stable even above 270 kph, but the steering is much more responsive and better balanced with the GT2 rear sway bar (only about $575 at the dealer) and the toe settings of the GT3RS! It completely changed the car where you can very easily overpower the rear end out on highway on-ramps and increase exit speed!
Ya I had PS4S on a few different sets over the years and love them, digging performance of the RE-71R but man are they loud... you are spot on there. Going to keep the Champion RS98/RE-71R setup as a track set until the tires are toast then might sell for a meaty 18" track set down the road (haven't done much research here). Regular set will be LMs/PS4S. My tech said he went pretty GT3ish on the alignment last week, the toe was quite a bit off. I'm on bilstein b16 kit and am at -1.26F camber and -1.76R camber now with the toe dialed in, feels great on the few canyon runs I've done so far, loads of grip. haven't pushed her past 120mph/195kmh yet but feels super solid up to that point. May have to do the GT2 Sway but I will say coming from a big heavy Audi it already feels insanely responsive & balanced on the bilsteins.
#27
Rennlist Member
I just installed 325/30/19 and 255/35/19s on my turbo. Wheels are 997.1 GT2 wheels. 5mm spacers all around. Stock suspension. Looks better than stock sizes IMO. Does a better job of filling up the wheel well.
#29
Fitment looks spot on, she is a beaut. Carrera Red interior? Mine's full leather Carrera Red with a few bits swapped out (997.2 flat bottom alcantara steering wheel & GT3 alcantara shifter/boot, black center console).
[…] My tech said he went pretty GT3ish on the alignment last week, the toe was quite a bit off. I'm on bilstein b16 kit and am at -1.26F camber and -1.76R camber now with the toe dialed in, feels great on the few canyon runs I've done so far, loads of grip. […] it already feels insanely responsive & balanced on the bilsteins.
[…] My tech said he went pretty GT3ish on the alignment last week, the toe was quite a bit off. I'm on bilstein b16 kit and am at -1.26F camber and -1.76R camber now with the toe dialed in, feels great on the few canyon runs I've done so far, loads of grip. […] it already feels insanely responsive & balanced on the bilsteins.
camber wise I’m stuck at -1.4°F and -1.8°Rear and went with the GT2 spec a few weeks back to see if I preferred it better one it warms up, giving me 0.11 total (0.05 and 0.06 each side) up front and 0.42 total in the rear… it should make pointing the car/steering quite responsive, but I’ll see if with the added power and the rear sway bar at mid-setting whether or not the back is still stable while remaining easy to oversteer since I don’t really track the car often and I like coming out of turns with a slight oversteer.
Last edited by Stark997; 02-21-2024 at 12:53 AM.
The following 2 users liked this post by Stark997:
cjcam930 (02-21-2024),
kasperberry (02-21-2024)
#30
Rennlist Member
It is actually extended Carrera Red Natural Leather with deviated carpets (black) and Alcantara roof liner… I’m actually thinking of going for a 991.2 updated steering wheel but it’d have to be black… mind to share how yours look as I’m hesitant if it would actually look aesthetically pleasing considering it’d be a big black piece in the center of a red dash (photo of mine as a reference).
camber wise I’m stuck at -1.4°F and -1.8°Rear and went with the GT2 spec a few weeks back to see if I preferred it better one it warms up, giving me 0.11 total (0.05 and 0.06 each side) up front and 0.42 total in the rear… it should make pointing the car/steering quite responsive, but I’ll see if with the added power and the rear sway bar at mid-setting whether or not the back is still stable while remaining easy to oversteer since I don’t really track the car often and I like coming out of turns with a slight oversteer.
camber wise I’m stuck at -1.4°F and -1.8°Rear and went with the GT2 spec a few weeks back to see if I preferred it better one it warms up, giving me 0.11 total (0.05 and 0.06 each side) up front and 0.42 total in the rear… it should make pointing the car/steering quite responsive, but I’ll see if with the added power and the rear sway bar at mid-setting whether or not the back is still stable while remaining easy to oversteer since I don’t really track the car often and I like coming out of turns with a slight oversteer.
The following users liked this post:
Stark997 (02-21-2024)