Tire Sizing and the Star Specs
Jul 16, 2008, 10:11 PM
#32
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First off this tire is amazing. I track my car often and they are great....
Second, schuber.... Do you in the next year or so intend to buy a new set off wheels? If so i would go with the 255/40/17. Mainly because they will fit stock, but if you decide to go with lets say a 17 x 9 or 17 x 9.5 those tires will still fit perfectly.
But if you decide to keep your BBS then go with the stock size. i ran 245/45/17 azenias and didnt like them at all. and 235/40 seems to small. thats is my advice to you!
Second, schuber.... Do you in the next year or so intend to buy a new set off wheels? If so i would go with the 255/40/17. Mainly because they will fit stock, but if you decide to go with lets say a 17 x 9 or 17 x 9.5 those tires will still fit perfectly.
But if you decide to keep your BBS then go with the stock size. i ran 245/45/17 azenias and didnt like them at all. and 235/40 seems to small. thats is my advice to you!
Aug 7, 2008, 09:50 AM
#35
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I have never understood the aversion to 245/45R17 on the stock 17x8 rims. They work perfectly fine.
Look at the facts: that size is only 0.3" taller than the stock size. That's virtually negligible, considering the speedometer difference. 245/45 will cause your speedometer at 60mph to be only 0.8mph off versus stock.
By the time you wear the tread away, 245/45 is actually shorter in diameter than a fresh set of 235/45. I've measured this myself.
People also argue that the increased width will cause sidewall flex. Well, if you get a tire with a thick sidewall, like the RE-01R, that is not an issue. Consider that the ideal size according to every tire manufacturer for a 245/45 is the 17x8 size rim. This is the size they mount the tire on to get the specs that are published to consumers.
I have 245/45R17 RE-01R's on my Evo right now and I think it works great, especially for autox. There is barely any speedometer difference, and with ideal pressures it has no more sidewall flex than the stock size. Visually, the sidewall is perfectly vertical, it does not "bulge out" from the rims as if you had gotten a really wide tire.
I wish more people would actually try 245/45 for themselves before complaining that it's not a good size to use. It's also usually cheaper for any given tire compared to 235/45 and 255/40.
Look at the facts: that size is only 0.3" taller than the stock size. That's virtually negligible, considering the speedometer difference. 245/45 will cause your speedometer at 60mph to be only 0.8mph off versus stock.
By the time you wear the tread away, 245/45 is actually shorter in diameter than a fresh set of 235/45. I've measured this myself.
People also argue that the increased width will cause sidewall flex. Well, if you get a tire with a thick sidewall, like the RE-01R, that is not an issue. Consider that the ideal size according to every tire manufacturer for a 245/45 is the 17x8 size rim. This is the size they mount the tire on to get the specs that are published to consumers.
I have 245/45R17 RE-01R's on my Evo right now and I think it works great, especially for autox. There is barely any speedometer difference, and with ideal pressures it has no more sidewall flex than the stock size. Visually, the sidewall is perfectly vertical, it does not "bulge out" from the rims as if you had gotten a really wide tire.
I wish more people would actually try 245/45 for themselves before complaining that it's not a good size to use. It's also usually cheaper for any given tire compared to 235/45 and 255/40.
Last edited by sleeper3; Aug 7, 2008 at 09:58 AM.
Aug 7, 2008, 10:17 AM
#36
^I asked the same question in the STU thread, and everyone hands down swore the 40 series was faster and handled better.
Coming from some of the fastest guys who are nationally competitive and had tried it, I decided to listen to them. If you can be faster than people on the 40 series, more power to you, and let us know!
Coming from some of the fastest guys who are nationally competitive and had tried it, I decided to listen to them. If you can be faster than people on the 40 series, more power to you, and let us know!
Aug 7, 2008, 12:24 PM
#37
^I asked the same question in the STU thread, and everyone hands down swore the 40 series was faster and handled better.
Coming from some of the fastest guys who are nationally competitive and had tried it, I decided to listen to them. If you can be faster than people on the 40 series, more power to you, and let us know!
Coming from some of the fastest guys who are nationally competitive and had tried it, I decided to listen to them. If you can be faster than people on the 40 series, more power to you, and let us know!
On the street I run the 45 series though for the simple fact that I've tried both sizes (245/40 and 245/45) in several tires and use the 40 for autocross. Consequently I have a bunch of 45s laying around. The taller tires are great in that they provide a better ride, longer 5th gear, marginally better mileage and an accurate speedo at 70mph.
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Last edited by donour; Aug 7, 2008 at 12:28 PM.
Aug 7, 2008, 12:46 PM
#38
Oh really? Because with sufficient front camber (2.7-3.0 degrees), I've found ideal front pressures to be 32 psi on the RE01Rs. That's with the 45. The 40s provide best grip down around 31 (on asphalt). EDIT: I think I was the only person at SCCA nationals, ever, to run the 245/45 RE01R.
d
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Aug 7, 2008, 01:04 PM
#39
I agree, as I am continually surprised at how low of pressures I can effectively run on 245/40/17 Z1s. I only run over 34psi for the first few runs to heat them up faster for the later runs, which are around 32psi. I'm still learning how this works with camber settings, but mine are a bit stretched on 9.5" wheels.
I ran 9" wheels last season and 8.5" ones this year.
d
Aug 7, 2008, 01:08 PM
#40
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Yup. The 40 series is a better STU tire -- no doubt. The gearing is better (at least for the Evo which has a pretty long 2nd) and the turn in is more crisp. They also seem to heat up less than 45.
On the street I run the 45 series though for the simple fact that I've tried both sizes (245/40 and 245/45) in several tires and use the 40 for autocross. Consequently I have a bunch of 45s laying around. The taller tires are great in that they provide a better ride, longer 5th gear, marginally better mileage and an accurate speedo at 70mph.
Oh really? Because with sufficient front camber (2.7-3.0 degrees), I've found ideal front pressures to be 32 psi on the RE01Rs. That's with the 45. The 40s provide best grip down around 31 (on asphalt). EDIT: I think I was the only person at SCCA nationals, ever, to run the 245/45 RE01R.
d
On the street I run the 45 series though for the simple fact that I've tried both sizes (245/40 and 245/45) in several tires and use the 40 for autocross. Consequently I have a bunch of 45s laying around. The taller tires are great in that they provide a better ride, longer 5th gear, marginally better mileage and an accurate speedo at 70mph.
Oh really? Because with sufficient front camber (2.7-3.0 degrees), I've found ideal front pressures to be 32 psi on the RE01Rs. That's with the 45. The 40s provide best grip down around 31 (on asphalt). EDIT: I think I was the only person at SCCA nationals, ever, to run the 245/45 RE01R.
d
Overall, I'm just addressing the negative vibe of the 245/45, when you get down to it, it's still a good size to use for daily driving and autox, especially compared to the stock 235/45 size. It's not as bad as some people make it out to be.
Last edited by sleeper3; Aug 7, 2008 at 01:11 PM.
