Narrowing Down Tires...
12-29-09, 06:26 PM
#31
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Brakes are a lot more than feel. They're also about fade, wear, dusting, wear on rotor, agressivness and etc. A pad that will let you brake earlier without lockup, glazing or overheating will let you increase your lap times. I agree with you on good vs great tires, but, as I have said, I have read nothing but good things about the Dunlops. But, they are new to the marketplace and not included in many tests. I would love to see a comparison test between the PS2 and the Sport Maxx TT on the F. On paper they look pretty equal to me. Here are two Tire Rack Tests, each containing different Hi-Po Tires, the only common tire used on both tests was the Continental ContiSportContact 3. In the tests the Continental was beaten by either the PS2 or the Dunlop.
http://www.tirerack.com/tires/tests/...%3D73YR9SMTTXL
http://www.tirerack.com/tires/tests/...y.jsp?ttid=101
I guess my point is, there are alternatives, and IMHO, the PS2 while being a great tire, may or may not be the best overall choice for the F. But, again, IMHO, the F is undertired and should have come with wider tires, both front and rear.
If you're comfortable with the the PS2, stick with it, I'm sure you'll be extremely happy. But me, I want a wider tire, and from my past experience with Dunlop and from the information I've gleaned I will be going with the Sport Maxx TT in wider fitments than stock. Will I make the right choice, I don't really know, but my gut tells me, Yes. Just as a point of interest, when it's time to replace my brake pads, I will be going with Ferodos. Again, from past experience.
Lou
http://www.tirerack.com/tires/tests/...%3D73YR9SMTTXL
http://www.tirerack.com/tires/tests/...y.jsp?ttid=101
I guess my point is, there are alternatives, and IMHO, the PS2 while being a great tire, may or may not be the best overall choice for the F. But, again, IMHO, the F is undertired and should have come with wider tires, both front and rear.
If you're comfortable with the the PS2, stick with it, I'm sure you'll be extremely happy. But me, I want a wider tire, and from my past experience with Dunlop and from the information I've gleaned I will be going with the Sport Maxx TT in wider fitments than stock. Will I make the right choice, I don't really know, but my gut tells me, Yes. Just as a point of interest, when it's time to replace my brake pads, I will be going with Ferodos. Again, from past experience.
Lou
Same is true for tires. Here's the problem no one seems to understand - if I compare the "standard" PS2 to the Kumho, Toyo, Dunlop, or Nitto, I'm making a fair comparison. If I compare the Lexus specific PS2 (or Bridgestone for that matter) ON THE IS-F, it is NOT fair at all because these tires have been tweaked to work BETTER on the IS-F. If you do a little research you'll also see you pay more for Lexus specific tires.
Tire tests are pretty meaningless in the real world unless you own the car the testers used for their comparison. Saying XYZ tires worked best on our test 328i doesn't mean beans about how it will work on a Honda Civic or a CTS-V Cadillac, so buying XYZ tires for your Honda or Caddy based on those test results is absolutely foolish.
Going to the Tire Rack and looking at their comparison tests, you'll almost always see them using a BMW 3 series sedan. We don't own one of these. The tires winning this comparison on a different car means little to nothing for an IS owner. The comparisons themselves are typically flawed because they don't even tune the tire pressures for optimum performance on each tire brand. They run the recommended OEM pressure because that's what the majority of owners will do.
Remember, tire pressure determines the tire's spring rate. It acts in combination with the suspension's spring rate, so adjusting the air +/-3 psi can make a HUGE difference in performance. But these tests are difficult enough to complete in a reasonable time without adding the possibility of actually optimizing tire pressures for each model tested on the day and time the test is being completed.
At the end of the day, I'll take a tire specifically made for the car over a generic tire simply because I know the customized model will almost invariably outperform the generic tire with a minimum of fuss and experimentation. It doesn't mean the car won't drive better with a different setup, it just means it's going to work very well with the least amount of grief on the model specific tires.
I've said before, I'd really like to see the IS-F on 315s all the way around. I think it would really emphasize the chassis work Lexus did when I'm out on the track. But Lexus has to build a car for the masses, so it needs to be on tires it can use in rain, light snow, AND dry pavement of all kinds. So we get narrower tires than would be ideal for a track only car. When you say, "I'm getting wider XYZ tires than the OEM tires because it will perform better", you're really saying "I'm HOPING I get better performance because XYZ has a good reputation and I'm planning to try to optimize my results by changing the OEM set up." As long as you never compete against a watch on a closed course, you can honestly say one feels better than the other. When you pull out the watch and start cutting some lap times, you'll find truth about feel and how wrong it can be.
There are so many variables affected by tire selection, it would take an entire tome to cover the subject. Something as simple as a small change in rolling diameter affects ride height, roll center, scrub radius, roll couple, roll axis, center of gravity...and you thought you just needed a bigger tire...it might all work out well. It might work out like crap. Crap is the more common result. It's hard to get it right and easy to screw it up.
That's a lot of why I say you'll be hard pressed to beat the PS2s.
12-29-09, 09:07 PM
#32
Well I just got my Toyo's on... It will take sometime to break them in until I can really test the traction...
But right out of the gate the rear end was breaking lose more easily than my Bridgestones... But I'll give it about a 500 mile break in before I really start expect feeling a difference...
But right out of the gate the rear end was breaking lose more easily than my Bridgestones... But I'll give it about a 500 mile break in before I really start expect feeling a difference...
12-29-09, 09:46 PM
#33
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Brakes are all about feel. Pads will not make your lap times lower (increase? no, don't want that for sure..) and if I have to brake earlier there's something wrong. I want to brake as late as possible for best lap times. Sure, if you buy the wrong pads and they glaze you're screwed. But if the compound is in its sweet spot for operating temperature, then it really is all about how it feels to you and your ability to judge impending lockup successfully with a minimum of mental effort. Driving fast all comes down to mental effort and how much attention you need to complete a given driving task. The more attention something takes, the harder it is to focus on the three most important elements - course, heading, and traction.
Same is true for tires. Here's the problem no one seems to understand - if I compare the "standard" PS2 to the Kumho, Toyo, Dunlop, or Nitto, I'm making a fair comparison. If I compare the Lexus specific PS2 (or Bridgestone for that matter) ON THE IS-F, it is NOT fair at all because these tires have been tweaked to work BETTER on the IS-F. If you do a little research you'll also see you pay more for Lexus specific tires.
Tire tests are pretty meaningless in the real world unless you own the car the testers used for their comparison. Saying XYZ tires worked best on our test 328i doesn't mean beans about how it will work on a Honda Civic or a CTS-V Cadillac, so buying XYZ tires for your Honda or Caddy based on those test results is absolutely foolish.
Going to the Tire Rack and looking at their comparison tests, you'll almost always see them using a BMW 3 series sedan. We don't own one of these. The tires winning this comparison on a different car means little to nothing for an IS owner. The comparisons themselves are typically flawed because they don't even tune the tire pressures for optimum performance on each tire brand. They run the recommended OEM pressure because that's what the majority of owners will do.
Remember, tire pressure determines the tire's spring rate. It acts in combination with the suspension's spring rate, so adjusting the air +/-3 psi can make a HUGE difference in performance. But these tests are difficult enough to complete in a reasonable time without adding the possibility of actually optimizing tire pressures for each model tested on the day and time the test is being completed.
At the end of the day, I'll take a tire specifically made for the car over a generic tire simply because I know the customized model will almost invariably outperform the generic tire with a minimum of fuss and experimentation. It doesn't mean the car won't drive better with a different setup, it just means it's going to work very well with the least amount of grief on the model specific tires.
I've said before, I'd really like to see the IS-F on 315s all the way around. I think it would really emphasize the chassis work Lexus did when I'm out on the track. But Lexus has to build a car for the masses, so it needs to be on tires it can use in rain, light snow, AND dry pavement of all kinds. So we get narrower tires than would be ideal for a track only car. When you say, "I'm getting wider XYZ tires than the OEM tires because it will perform better", you're really saying "I'm HOPING I get better performance because XYZ has a good reputation and I'm planning to try to optimize my results by changing the OEM set up." As long as you never compete against a watch on a closed course, you can honestly say one feels better than the other. When you pull out the watch and start cutting some lap times, you'll find truth about feel and how wrong it can be.
There are so many variables affected by tire selection, it would take an entire tome to cover the subject. Something as simple as a small change in rolling diameter affects ride height, roll center, scrub radius, roll couple, roll axis, center of gravity...and you thought you just needed a bigger tire...it might all work out well. It might work out like crap. Crap is the more common result. It's hard to get it right and easy to screw it up.
That's a lot of why I say you'll be hard pressed to beat the PS2s.
Same is true for tires. Here's the problem no one seems to understand - if I compare the "standard" PS2 to the Kumho, Toyo, Dunlop, or Nitto, I'm making a fair comparison. If I compare the Lexus specific PS2 (or Bridgestone for that matter) ON THE IS-F, it is NOT fair at all because these tires have been tweaked to work BETTER on the IS-F. If you do a little research you'll also see you pay more for Lexus specific tires.
Tire tests are pretty meaningless in the real world unless you own the car the testers used for their comparison. Saying XYZ tires worked best on our test 328i doesn't mean beans about how it will work on a Honda Civic or a CTS-V Cadillac, so buying XYZ tires for your Honda or Caddy based on those test results is absolutely foolish.
Going to the Tire Rack and looking at their comparison tests, you'll almost always see them using a BMW 3 series sedan. We don't own one of these. The tires winning this comparison on a different car means little to nothing for an IS owner. The comparisons themselves are typically flawed because they don't even tune the tire pressures for optimum performance on each tire brand. They run the recommended OEM pressure because that's what the majority of owners will do.
Remember, tire pressure determines the tire's spring rate. It acts in combination with the suspension's spring rate, so adjusting the air +/-3 psi can make a HUGE difference in performance. But these tests are difficult enough to complete in a reasonable time without adding the possibility of actually optimizing tire pressures for each model tested on the day and time the test is being completed.
At the end of the day, I'll take a tire specifically made for the car over a generic tire simply because I know the customized model will almost invariably outperform the generic tire with a minimum of fuss and experimentation. It doesn't mean the car won't drive better with a different setup, it just means it's going to work very well with the least amount of grief on the model specific tires.
I've said before, I'd really like to see the IS-F on 315s all the way around. I think it would really emphasize the chassis work Lexus did when I'm out on the track. But Lexus has to build a car for the masses, so it needs to be on tires it can use in rain, light snow, AND dry pavement of all kinds. So we get narrower tires than would be ideal for a track only car. When you say, "I'm getting wider XYZ tires than the OEM tires because it will perform better", you're really saying "I'm HOPING I get better performance because XYZ has a good reputation and I'm planning to try to optimize my results by changing the OEM set up." As long as you never compete against a watch on a closed course, you can honestly say one feels better than the other. When you pull out the watch and start cutting some lap times, you'll find truth about feel and how wrong it can be.
There are so many variables affected by tire selection, it would take an entire tome to cover the subject. Something as simple as a small change in rolling diameter affects ride height, roll center, scrub radius, roll couple, roll axis, center of gravity...and you thought you just needed a bigger tire...it might all work out well. It might work out like crap. Crap is the more common result. It's hard to get it right and easy to screw it up.
That's a lot of why I say you'll be hard pressed to beat the PS2s.
12-29-09, 10:43 PM
#34
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Same is true for tires. Here's the problem no one seems to understand - if I compare the "standard" PS2 to the Kumho, Toyo, Dunlop, or Nitto, I'm making a fair comparison. If I compare the Lexus specific PS2 (or Bridgestone for that matter) ON THE IS-F, it is NOT fair at all because these tires have been tweaked to work BETTER on the IS-F. If you do a little research you'll also see you pay more for Lexus specific tires.
.
.
Again what makes these PS2 tires specific to the IS-F other than their 225/255 fitment?
12-30-09, 09:10 AM
#36
Tires, Brake Pads, and etc. What's the difference? Both made by a third party and designed for the F. Inexpensive tires? Who said anything about inexpensive tires? I'm not recommending anyone go with a cheap tire. I certainly wont. As I said in my post (post #4) I will be going with Dunlop SP Sport Maxx TT. 245/35/19 in front and 275/30/19 in back. This is not a cheap tire, but Dunlop's top performance tire. Less expensive than the PS2s, but certainly not cheap. I have had extremely good luck with Dunlop Hi-Po tires in the past, and everything I have read about this new tire has been positive.
Lou
Lou
Are you going to run those on the stock wheels, if so do you foresee any rubbing or fitment issues?
12-30-09, 10:36 AM
#37
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What makes these PS2 tires specific to the IS-F other than their 225/255 fitment?
12-30-09, 12:04 PM
#38
http://www.lexusfforum.com/forums/showthread.php?t=1753
Lou
Last edited by flowrider; 12-30-09 at 12:12 PM.
12-30-09, 12:21 PM
#39
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I talked to Michelin's lead engineer for the IS-F tires at the Lexus Driving Academy.
They're constructed differently than the run of the mill PS2. The belts were modified to allow the outer tread blocks to form a gap free strip of rubber under lateral load. Being able to do this means the tire performs more like a slick under hard cornering. Since the weight of the car and the spring and damping rates affect the way the tire is loaded, the ideal solution needs to be optimized for the specific car.
They're constructed differently than the run of the mill PS2. The belts were modified to allow the outer tread blocks to form a gap free strip of rubber under lateral load. Being able to do this means the tire performs more like a slick under hard cornering. Since the weight of the car and the spring and damping rates affect the way the tire is loaded, the ideal solution needs to be optimized for the specific car.
12-30-09, 12:27 PM
#40
^^^^OK my friend. You believe what you think is true, and I'll believe what I think is true. BTW, I worked in the tire retail industry about 25 years ago, and know a little bit about how it works. We could go on with our "discussion" but, in the end, neither of us would change our minds, so let's call this draw, shall we?
Lou
Lou
12-30-09, 12:46 PM
#41
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So what it sounds like you're saying is they're all black, they're all round and if the fit on the rim they must be good. If that were true, we should all just buy Kumhos or General UHPs and be happy.
Retail? 25 years ago? OK. Apparently you've never dealt with the engineering end of tire manufacturing. People who actually manufacture tires - the folks who attach the tread to the carcass - will tell you they won't run a tire they didn't personally assemble because there are intricacies in the assembly process and some people don't do it "right" especially those people who ride motorcycles.
As another example - the Michelins for the Viper are actually Pilot Sport Cups with a PS2 sidewall. Definitely a very different tire.
Obviously my experience is different from yours.
Retail? 25 years ago? OK. Apparently you've never dealt with the engineering end of tire manufacturing. People who actually manufacture tires - the folks who attach the tread to the carcass - will tell you they won't run a tire they didn't personally assemble because there are intricacies in the assembly process and some people don't do it "right" especially those people who ride motorcycles.
As another example - the Michelins for the Viper are actually Pilot Sport Cups with a PS2 sidewall. Definitely a very different tire.
Obviously my experience is different from yours.
Last edited by lobuxracer; 12-30-09 at 12:56 PM.
12-30-09, 01:28 PM
#42
Here's the problem no one seems to understand - if I compare the "standard" PS2 to the Kumho, Toyo, Dunlop, or Nitto, I'm making a fair comparison. If I compare the Lexus specific PS2 (or Bridgestone for that matter) ON THE IS-F, it is NOT fair at all because these tires have been tweaked to work BETTER on the IS-F. If you do a little research you'll also see you pay more for Lexus specific tires.
great point. i also read that c&d review and gave serious consideration to those other tires but will probably stick what is recommended for the F by lexus.
for me, it seems the more i stick with OEM, the less headache i have in the long run which is well worth the extra price. i bought cheaper replacement parts and got extra modifications in the past for other cars and 9/10 times they failed quickly in their own ways.
12-30-09, 01:40 PM
#43
So what it sounds like you're saying is they're all black, they're all round and if the fit on the rim they must be good. If that were true, we should all just buy Kumhos or General UHPs and be happy.
Retail? 25 years ago? OK. Apparently you've never dealt with the engineering end of tire manufacturing. People who actually manufacture tires - the folks who attach the tread to the carcass - will tell you they won't run a tire they didn't personally assemble because there are intricacies in the assembly process and some people don't do it "right" especially those people who ride motorcycles.
As another example - the Michelins for the Viper are actually Pilot Sport Cups with a PS2 sidewall. Definitely a very different tire.
Obviously my experience is different from yours.
Retail? 25 years ago? OK. Apparently you've never dealt with the engineering end of tire manufacturing. People who actually manufacture tires - the folks who attach the tread to the carcass - will tell you they won't run a tire they didn't personally assemble because there are intricacies in the assembly process and some people don't do it "right" especially those people who ride motorcycles.
As another example - the Michelins for the Viper are actually Pilot Sport Cups with a PS2 sidewall. Definitely a very different tire.
Obviously my experience is different from yours.
Lou
12-30-09, 02:20 PM
#44
alot of it comes downt to money too guys...
PS2's will run ya $1400 for tires
Hankook V12's are $720
IMO, the PS2's a nicer tire, but not double the tire the Hankook is. I'll save 50% and go with the Hankooks. I'm not pushing my car to the limit every time I drive it, heck its my daily driver and I'm running to work/ect...
don't forget to talk about the money part of it though, is all i'm saying. its the absoulte biggest factor of all, otherwise people would ovbiously go with the 'best' Mich/Bridge
PS2's will run ya $1400 for tires
Hankook V12's are $720
IMO, the PS2's a nicer tire, but not double the tire the Hankook is. I'll save 50% and go with the Hankooks. I'm not pushing my car to the limit every time I drive it, heck its my daily driver and I'm running to work/ect...
don't forget to talk about the money part of it though, is all i'm saying. its the absoulte biggest factor of all, otherwise people would ovbiously go with the 'best' Mich/Bridge
12-30-09, 02:37 PM
#45
Nope - read through all three pages of this thread.
http://www.lexusfforum.com/forums/showthread.php?t=1753
I know that Lexus and Michelin say this is the case. But, in my own mind, I find this very hard to believe. The rubber compound and all the engineering that went into the design of the PS2, really makes it difficult for me to believe that there are differences in the tires assigned to each make of automobile. I believe this is more PR by both companies.
Lou
http://www.lexusfforum.com/forums/showthread.php?t=1753
I know that Lexus and Michelin say this is the case. But, in my own mind, I find this very hard to believe. The rubber compound and all the engineering that went into the design of the PS2, really makes it difficult for me to believe that there are differences in the tires assigned to each make of automobile. I believe this is more PR by both companies.
Lou