Max tire diameter, 996 NB?
Thread Starter
Instructor
Joined: Jan 2013
Posts: 186
Likes: 4
From: Palo Alto, CA USA
But I think I'm leaning in your direction: 235/40-18 (25.4" diam), 285/35-18 (25.9" diam). Difference is 2% which should be OK. And tread wear from 10/32 to 2/32 is 0.5" in diameter (another 2%) so by the time the rears are at tread limit the diameter difference will be 0.25". New rears with half-worn fronts might be interesting though, with a 3% diam difference. Maybe by then there will be a 295/30-18.
Rennlist Member
Joined: Jul 2005
Posts: 680
Likes: 62
From: Chicago, IL
I think you will be fine with PSS at 235/40/18 and 285/35/18.
I am running 235/35/19 and 305/30/19 with no rubbing, on my non lowered 996 40th.
In fact, I've ordered 235/40/18 and 295/35/18 BFG Rivals
As 6ta1 suggested, the front tire diameter will be the limiting factor at full lock.
The rears can go very tall as my fitment suggests.
I am running 235/35/19 and 305/30/19 with no rubbing, on my non lowered 996 40th.
In fact, I've ordered 235/40/18 and 295/35/18 BFG Rivals
As 6ta1 suggested, the front tire diameter will be the limiting factor at full lock.
The rears can go very tall as my fitment suggests.
Racer
Joined: Jul 2012
Posts: 250
Likes: 7
From: Dallas, TX
I think you will be fine with PSS at 235/40/18 and 285/35/18.
I am running 235/35/19 and 305/30/19 with no rubbing, on my non lowered 996 40th.
In fact, I've ordered 235/40/18 and 295/35/18 BFG Rivals
As 6ta1 suggested, the front tire diameter will be the limiting factor at full lock.
The rears can go very tall as my fitment suggests.
I am running 235/35/19 and 305/30/19 with no rubbing, on my non lowered 996 40th.
In fact, I've ordered 235/40/18 and 295/35/18 BFG Rivals
As 6ta1 suggested, the front tire diameter will be the limiting factor at full lock.
The rears can go very tall as my fitment suggests.
I was thinking about going 275/30/19 for the rears which would solve the diameter issue as well as balance better the handling (I have not enough oversteer on the dry and too much on the wet)
Three Wheelin'
Joined: Jun 2012
Posts: 1,393
Likes: 7
From: San Diego
I'm running wb offset wheel with 295/30, stock height (for now) and no rubbing.
At stock height, I wouldn't be concerned upping to a 35 series tire. You might get better mpg (.5mpg) with the slightly taller ratio.
+1
At stock height, I wouldn't be concerned upping to a 35 series tire. You might get better mpg (.5mpg) with the slightly taller ratio.
+1
Thread Starter
Instructor
Joined: Jan 2013
Posts: 186
Likes: 4
From: Palo Alto, CA USA
I asked Tire Rack what they would recommend and the response is:
The super sport sizes we would suggest you use on the car would be 225/40-18 and 265/35-18. We cannot ensure larger sized tire pairings will work correctly and not rub.
Yow that's quite a different approach from what you all have recommended.
According to Tire Rack's web site, the diameter of these is 25.3" (rear), 25.1" (front).
275/35-18 are also available, diameter 25.6".
Again I'm not after the absolute maximum possible grip by pushing width. I'd rather get the PSSs in whatever size makes the most sense. I like the idea of keeping with the stock front sizes to prevent rub.
The super sport sizes we would suggest you use on the car would be 225/40-18 and 265/35-18. We cannot ensure larger sized tire pairings will work correctly and not rub.
According to Tire Rack's web site, the diameter of these is 25.3" (rear), 25.1" (front).
275/35-18 are also available, diameter 25.6".
Again I'm not after the absolute maximum possible grip by pushing width. I'd rather get the PSSs in whatever size makes the most sense. I like the idea of keeping with the stock front sizes to prevent rub.
Nordschleife Master
Joined: Nov 2008
Posts: 5,815
Likes: 59
From: Mooresville, IN (Life Long Cheesehead)
Maybe a typo (as in the other thread about x74 first impressions)? PSS doesn't come in 295/35-18, confirmed both at the Michelin and Tire Rack sites.
But I think I'm leaning in your direction: 235/40-18 (25.4" diam), 285/35-18 (25.9" diam). Difference is 2% which should be OK. And tread wear from 10/32 to 2/32 is 0.5" in diameter (another 2%) so by the time the rears are at tread limit the diameter difference will be 0.25". New rears with half-worn fronts might be interesting though, with a 3% diam difference. Maybe by then there will be a 295/30-18.
But I think I'm leaning in your direction: 235/40-18 (25.4" diam), 285/35-18 (25.9" diam). Difference is 2% which should be OK. And tread wear from 10/32 to 2/32 is 0.5" in diameter (another 2%) so by the time the rears are at tread limit the diameter difference will be 0.25". New rears with half-worn fronts might be interesting though, with a 3% diam difference. Maybe by then there will be a 295/30-18.
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Rennlist Member
Joined: Jul 2005
Posts: 680
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From: Chicago, IL
balefire, I am interested in your feedback. Have you tried any other size for the rears? The 295/30 or 305/30 are quite larger (in diameter) than our 235/35 fronts and I have been wondering if that makes the PSM act too quickly (thinking the rears start to spin earlier than they really do since they are like 5% taller than stock)
I was thinking about going 275/30/19 for the rears which would solve the diameter issue as well as balance better the handling (I have not enough oversteer on the dry and too much on the wet)
I was thinking about going 275/30/19 for the rears which would solve the diameter issue as well as balance better the handling (I have not enough oversteer on the dry and too much on the wet)
I would consider changing alignment (max out camber front, 0 toe front, decrease toe rear, decrease camber rear) to reduce understeer before changing tires.
I would consider increasing my front tire width before I decrease the rear tire to reduce understeer.
Burning Brakes
Joined: Jan 2008
Posts: 1,138
Likes: 8
From: Richmond, VA
With your lowered x74 and keeping your rims, as others have said, the fronts determine max. I went through the same quandry you are in now, and just decided to spend a little more, and go with the right sized PS2s, which were under $1400 installed at costco, with road hazard, m&b, and N2 fill. I also use 7.5 mm spacers all.aroind from FVD. Some people, like me, just prefer Michelin tires because of past experiences, and afew $100 extra is worth it. Almost a year on the PS2 s and zero regrets. Alignment is the key to good wear. In my case, at or less than 5k miles ayear, they will last a very long time. Fun level and handling/ride are far more important than wear to me. What kind of miles per year do you expext to run?
Banned
Joined: Mar 2010
Posts: 7,697
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From: Chicago
IIRC, 265 is the standard stock size that came on '99-01 models. Starting in '02, they started coming with the 285 width as standard.
Banned
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From: Chicago