RS-3 vs Z1SS vs 595 RS-R vs RE-11 vs Z2 vs Rivals
08-19-2011, 05:51 AM
#301
Gernby - First, hankooks require more pressure. I'd recommend 35 PSI-ish for the street. That's definitely a huge part of it. Driving on the tires at 30 psi is like driving on big floppy pillows, so I wouldn't be surprised at your results. The feel that remains after pumping the tires up is probably largely your diameter change.
Second, have you considered that a big part of the higher rolling resistance is simply due to them being a stickier tire? When you add significantly more surface adhesion, like these tires do, you get more rolling resistance. So any other tire with similar traction properties would do the same thing.
Anyway, I don't think anyone in this thread is worried about rolling resistance. It was an interesting discovery to mention and I'm glad you did but now it seems like you're continually recommending people to steer away from them solely for that reason - that is not everyone else's main criteria for choosing a tire, least of all in this thread.
On another note, a little earlier people were talking about wet traction for RE11 vs Star spec - not sure if anyone else saw this month's GRM, but at least for their conditions/test the star specs were significantly faster in the wet.
Second, have you considered that a big part of the higher rolling resistance is simply due to them being a stickier tire? When you add significantly more surface adhesion, like these tires do, you get more rolling resistance. So any other tire with similar traction properties would do the same thing.
Anyway, I don't think anyone in this thread is worried about rolling resistance. It was an interesting discovery to mention and I'm glad you did but now it seems like you're continually recommending people to steer away from them solely for that reason - that is not everyone else's main criteria for choosing a tire, least of all in this thread.
On another note, a little earlier people were talking about wet traction for RE11 vs Star spec - not sure if anyone else saw this month's GRM, but at least for their conditions/test the star specs were significantly faster in the wet.
My issue is also unrelated to tire diameter. I had these same sized tires earlier last year, and they didn't cause this issue. I only had to change the tire size in my software dyno, and all the numbers worked out. With these tires, I have to add an additional ~5% correction on top of that.
Lastly, I don't understand what you mean by "continually recommending people to steer away ...". I've only mentioned it to ONE PERSON, who clearly said that he didn't think he needed the maximum performance. I think my advice was spot on for him.
08-19-2011, 07:06 AM
#302
Thread Starter
Gernby, have you considered that the RS may have more intertia and/or have a weight difference from your previous Sumitomos? Also, the RS3 tends to run wide for any given size; you may need to physically measure the diameter as well.
08-19-2011, 07:12 AM
#303
I'll play around with pressure more, but I'm already running higher pressure than before. From a physics standpoint, I don't see how the rubber compound would contribute much to the rolling resistance at all. I believe it is mostly due to the internal construction. I remember back in the 90's when Hoosier autocross tires were bias plys, and they had so much rolling resistance that it took an army of people to push the car forward at grid while all the guys running radials (BFG R1's, etc.) could push their cars one handed.
My issue is also unrelated to tire diameter. I had these same sized tires earlier last year, and they didn't cause this issue. I only had to change the tire size in my software dyno, and all the numbers worked out. With these tires, I have to add an additional ~5% correction on top of that.
I can also use my DL1 to get a pure acceleration difference between my stock tires and my RS3's once they come back after nationals next month, to see if I get a similar result.
You're right, it seemed like you had said it multiple times but looking back you were just defending your point for most of them. Sorry for the misunderstanding!
08-19-2011, 07:19 AM
#304
Anyway I'm at work and don't have it in front of me but from memory actually the R1R did not do very well. It was mid-pack and the star specs were actually faster than it. I believe the fastest tire in the wet was the advan neova, but only by a somewhat small margin over the dunlops.
I do think that the dunlops had a slight advantage in their test since the car has been tuned with dunlops the whole time, and the drivers are used to them. But still I don't think it's a huge effect.
08-19-2011, 07:47 AM
#305
Registered User
Originally Posted by rjones' timestamp='1313705180' post='20891866
Did the GRM test include the Toyo R1R? If so how did it do?
I guess the test was on wet performance. What tires did they test? Who won?
I have to start getting GRM.
I guess the test was on wet performance. What tires did they test? Who won?
I have to start getting GRM.
Anyway I'm at work and don't have it in front of me but from memory actually the R1R did not do very well. It was mid-pack and the star specs were actually faster than it. I believe the fastest tire in the wet was the advan neova, but only by a somewhat small margin over the dunlops.
I do think that the dunlops had a slight advantage in their test since the car has been tuned with dunlops the whole time, and the drivers are used to them. But still I don't think it's a huge effect.
08-19-2011, 08:34 AM
#306
I think we just need to drop the rolling resistance topic until someone has additional data. I agree that soft rubber would technically add to the rolling resistance, but I don't think it could account for the ~9 ft-lbs of torque I lost. I think the most obvious cause is a soft internal construction that gives a much larger contact patch at a given air pressure. If so, then I think raising the air pressure is a good thing to try.
12-12-2011, 08:37 AM
#310
I'm on my first set of RE-11s, but it's been said that they cycle really well and will hold grip down to the cords (or at least the tread wear bar). They might not grip like RS3s, but they won't fall off as fast when you have so much tread still left. I'll find out next season. My RE-11s have 3 track days on them so far, and I'm hoping they'll last me all of the 2012 season (hoping to make it to at least 9 S2KC events, minus 1 ACS event, and Laguna i still up in the air for me $$$$)... I might need to get tires towards the end.
