New tires - recommendations
Drifting
Joined: Jan 2009
Posts: 3,042
Likes: 84
From: Chesapeake, VA
Thanks for the replies everyone.
I wasn't aware that of the Super Sports, but I'll definitely give them a look. They don't seem to be that much more than the RE050A's that came OEM on my car. It seems people really like the Sumitomo's as well, so I'll probably investigate those a bit too.
As for climate, I live in Boston. I don't drive this car during the winter, but, for example, I did drive it today in 48F weather. I do a fair amount of auto-x during the year, no DE's though, and while it isn't my main purpose for the car, I would like the tires to up for the task as I tend to throw the car around a bit in my everyday driving.
sjfehr, when you say I can size up, how much is a safe limit, and what are the downfalls of doing so? My C4S came with 235/35-19 front and 305/30-19 rears. I know nothing about tires except the fact that the first number indicates in mm, the width. Would something like a 245/35ZR19 fit the front? What other sizes would be safe for the rears?
I wasn't aware that of the Super Sports, but I'll definitely give them a look. They don't seem to be that much more than the RE050A's that came OEM on my car. It seems people really like the Sumitomo's as well, so I'll probably investigate those a bit too.
As for climate, I live in Boston. I don't drive this car during the winter, but, for example, I did drive it today in 48F weather. I do a fair amount of auto-x during the year, no DE's though, and while it isn't my main purpose for the car, I would like the tires to up for the task as I tend to throw the car around a bit in my everyday driving.
sjfehr, when you say I can size up, how much is a safe limit, and what are the downfalls of doing so? My C4S came with 235/35-19 front and 305/30-19 rears. I know nothing about tires except the fact that the first number indicates in mm, the width. Would something like a 245/35ZR19 fit the front? What other sizes would be safe for the rears?
235/35R-19:
235 = the width of the tread in mm
35 = the aspect ratio of the sidewall, as a % of the tread width (sidewall = 35% of 235mm)
R = radial. Every DOT tire is a radial tire, so the R is often omitted.
19 = wheel diameter, in inches. (19" diameter=241mm radius)
RE-11 are available in these sizes:
235/35-19: 35%*235 + 241mm = 323mm radius
245/35-19: 35%*245 + 241mm = 327mm radius (1/8" higher)
255/35-19: 35%*255 + 241mm = 330mm radius (1/4" higher)
265/35-19: 35%*265 + 241mm = 334mm radius (3/8" higher)
275/30-19: 30%*275 + 241mm = 323mm radius (=)
So, the 245-265 will sit slightly higher, but the extra width will really help dial out some of the understeer I'm sure plagues you in autocross. The 275, while wider still, sits at exactly the same height due to the lower aspect ratio- same size sidewall as the 235, but smaller % of the width. I recommend researching this, and if the 275/30-19 fits on your wheels (9-10") and doesn't rub, going with that. I can guarantee you you're not the first person to see if these tires fit on a C4S so google or other rennlist members should turn up some experience in the matter.
Rennlist Member
Joined: Apr 2007
Posts: 1,924
Likes: 28
From: Tejas Hill Country
RE11 are fantastic tires. I'm also on my second set and I'm quite happy with them for mostly street and a little track.
http://macnugget.org/cars/tirecalc is good for calculating the impact of different tire sizes.
http://macnugget.org/cars/tirecalc is good for calculating the impact of different tire sizes.
Race Director
Joined: Mar 2006
Posts: 15,362
Likes: 198
From: Tampa
IMHO, PS2 (and PS3) are way overpriced for what you're getting. Dunlop Z1 Star Specs are as good, or better, performance than PS2 and RE-11 for about half the cost. Toyo R1R are fast, especially in the (relative) cold and wet, but I wouldn't put them on a car as heavy as a C4, as they can get greasy when it
Race Director
Joined: Mar 2006
Posts: 15,362
Likes: 198
From: Tampa
If you go onto TireRack and search tires by brand, you can get a list of the sizes they're offered in. Star Specs don't come in 19", so they're out. Sumis don't come wide enough in the rear. They'd fit with no issue, but if you're performance-minded, you don't want to use narrower tires. Nor do you really want to use Sumis if you're competing; they're a good value, but not a competition tire. So, unfortunately, the cheap options aren't really options for you. Luckily, RE-11 come in your OEM sizes and are very good tires with great wet/dry grip and great (relatively) cold traction and should work extremely well for you!
235/35R-19:
235 = the width of the tread in mm
35 = the aspect ratio of the sidewall, as a % of the tread width (sidewall = 35% of 235mm)
R = radial. Every DOT tire is a radial tire, so the R is often omitted.
19 = wheel diameter, in inches. (19" diameter=241mm radius)
RE-11 are available in these sizes:
235/35-19: 35%*235 + 241mm = 323mm radius
245/35-19: 35%*245 + 241mm = 327mm radius (1/8" higher)
255/35-19: 35%*255 + 241mm = 330mm radius (1/4" higher)
265/35-19: 35%*265 + 241mm = 334mm radius (3/8" higher)
275/30-19: 30%*275 + 241mm = 323mm radius (=)
So, the 245-265 will sit slightly higher, but the extra width will really help dial out some of the understeer I'm sure plagues you in autocross. The 275, while wider still, sits at exactly the same height due to the lower aspect ratio- same size sidewall as the 235, but smaller % of the width. I recommend researching this, and if the 275/30-19 fits on your wheels (9-10") and doesn't rub, going with that. I can guarantee you you're not the first person to see if these tires fit on a C4S so google or other rennlist members should turn up some experience in the matter.
235/35R-19:
235 = the width of the tread in mm
35 = the aspect ratio of the sidewall, as a % of the tread width (sidewall = 35% of 235mm)
R = radial. Every DOT tire is a radial tire, so the R is often omitted.
19 = wheel diameter, in inches. (19" diameter=241mm radius)
RE-11 are available in these sizes:
235/35-19: 35%*235 + 241mm = 323mm radius
245/35-19: 35%*245 + 241mm = 327mm radius (1/8" higher)
255/35-19: 35%*255 + 241mm = 330mm radius (1/4" higher)
265/35-19: 35%*265 + 241mm = 334mm radius (3/8" higher)
275/30-19: 30%*275 + 241mm = 323mm radius (=)
So, the 245-265 will sit slightly higher, but the extra width will really help dial out some of the understeer I'm sure plagues you in autocross. The 275, while wider still, sits at exactly the same height due to the lower aspect ratio- same size sidewall as the 235, but smaller % of the width. I recommend researching this, and if the 275/30-19 fits on your wheels (9-10") and doesn't rub, going with that. I can guarantee you you're not the first person to see if these tires fit on a C4S so google or other rennlist members should turn up some experience in the matter.
Rennlist Member
Joined: Jul 2009
Posts: 6,087
Likes: 51
From: MA
Race Director
Joined: Mar 2006
Posts: 15,362
Likes: 198
From: Tampa
Rennlist Member
Joined: Jul 2007
Posts: 452
Likes: 23
Fresh Meat for a C4S: Re-11s
Race Director
Joined: Nov 2009
Posts: 10,594
Likes: 8
From: THE Republic
When I compared the PS2's and the SuperSport's here's what i saw regarding Load ratings on 295's:
PS2 N1- 100y
PS2 N2- 100y
SS - 101y
so the SS's are ever so slightly higher rated (about 55lbs). Is this good enough? I need rears soon. tks
Banned
Joined: Jul 2010
Posts: 1,001
Likes: 2
From: Canton, Ct.
My tires aren't shot shot. I am choosing to wait.
Personally I don't think they will wait too much longer after the initial release to do the Porsche spec tires.
Certainly they would not want to loose the summer tire sales.
Personally I don't think they will wait too much longer after the initial release to do the Porsche spec tires.
Certainly they would not want to loose the summer tire sales.