silverESS

don't forget to flush.

------------------
you are not your fukking signature.

gavriil

Hahaha! I know.

------------------
Gabriel
CL Type S

fender4

LMFAO time for a group hug

EricL

China vs. US comes to mind...

Kung Fu better than kick boxing HEE
NO
Boxing better than Kung Fu.
No
Chinese Boxing better than Kung Fu
No
Grasshopper style better than lizard style.
No




THEN




------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

[This message has been edited by EricL (edited 04-14-2001).]

FDao

Gabriel,

I've been following this thread with great interests as both you and Eric have valid points; however, I would have to agree with Eric when you said that"The Higher the Rolling Resistance, the Better". Can you elucidate more on that? I agree that tires with large contact patch will likely have higher rolling resistance, but that does not necessarily translate to lateral grip. Grip has to do with not only contact patch but also with side wall flexing among other things.

I agree that screeching tire is not necessarily a bad thing. The tires are doing their jobs, but that it may very well be at the limits of their adhesions. It could also be due to the compounds of the tires.

Lastly, following Acura's manual will help you to avoid getting into trouble; however, I would ask this question: Why did Acura, with all its engineering marvel,choose a 215/50/17 tires in a Touring category? Could it be due to cost containment? Could it be due to the market that they are trying to appeal to?

I think every car has the potential to be better than it is coming out of the factory. So sticking to stock may be alright for the majority, but for those of us who want a little more, I believe Acura has provided that additional room for improvement.

Your thoughts.

------------------
Frank
01-S White/Parchment
Comptech Sways & Springs

gavriil

Frank,

I never said thge higher the rolling resistance the better. On the contrary. But you, yourself, go to the link that Eric posted earlier in the thread and experiment with different sizes. You will see that the lower the number the worse it is. Put in any size you want and you will see that results are consistent.

Why did Acura go with this tire in our car. Great question which I can only hypothesize but I can tell you for sure that it is a complex question of engineering as well as economics. You stated "could it be due to cost?" or something to that. Well, I can tell you that the MXMs are not cheap. So Acura did not go cheap with our OEM tires. Actually there are no Michelins that are cheap as far as I know (here nor in Europe from what I remember).

Other reasons:

The character of the car is not to be super sporty. So a Pilot tire would be out of the question yet Acura wanted some sportiness so they went with this excellent tire which combnies various traits. Yes, they went with an All Season tire but then again they went with a lower than average profile (50) which adds to handling accuracy. The tire profile combined with the relatively tall wheel (17 inches) adds to accurate steering even more.

Also, Michelins are always very qualitative tires. The company is one of the best tire makers today. Acura goes for quality always, it is part of their philosophy.

Finally, the MXM from what I remember is one of the most efficient tires in other respects. IT IS NOT ONLY ABOUT FRICKING GRIP like most people here think.

"Oh yeah...I am a mod freak...I know that the Potenzas and the Pilots are stickier tires...so I will chose them cos I like to mod my Acura...."

Piiiiisssseeess me off when people think like that. There are hundreds of variables that affect a tire's personality. Things like rolling resistance in regards to fuel economy not handling, tire noise which is very important in luxury cars, sidewall stiffeness which affects a lot of things, how the tire will behave if deflated suddenly at high speeds which might save one's life, how enviromentally friendly it is when discarded. And others.

So dont worry...like I said...Acura has the bucks to hire the best people and equipment and run the tests and come to conclusions.

ME, YOU, ERIC AND THE REST OF US HERE DO NOT HAVE ANY OF THE ABOVE. All we got is our individual taste as far as looks which I will not debate cos it is subjective, and eyes and brains to read, understand and follow the manual that Acura wrote. Some will, some wont. I belong to the former group.

------------------
Gabriel
CL Type S

Nashua_Night_Hawk

I vote that this thread should be closed. Better let the author delete it... it's going nowhere. Those who are happy with their stock tire that's excellent. Yes, the stock tire has excellent advantages, low rolling resistance, sqeaking noise when pushed hard, high load rating, XL rating, low wear (more miles !!!) All season good performance tire.... Not bad, hugh!

The NITTO are very low cost, only $151 for 235/40/18. UHP with W speed rating, lower load rating though, stick like glue on the corners. CLS feels like it got lowered on the HW, i.e. super stable (I just came from 60 miles trip, my passenger, a korean who drives a POS Tiburon, was all the way saying "this a fuking good car", Until I said "sit in, shut up, and hold on tight"... Yeah crusing at triple speed felt as if I am doing 60! however I needed to slow down saw cops pulling guys on the left shoulders

In addition, I am sure that MPG will suffer big time, as the nitto are broken-in, when I lift my right foot at 80, it quickly drops to 60 as if "stealth breaks" were applied. Basically it's the friction between the tire and the road. On the other hand, braking will surely be improved as we need improvement in the shitty stock breaking department.

I also would assume that the nitto would wear a bit faster, but I am planning to drve on them some 3 summers or 20k-25k miles.

Handling is much better than stock, no added noise so far on the HW. You can feel the steering wheel beter on HW and over imperfection in side roads. Also, the nitto would also squeak on hard cornners but what you expect they are still, not fully broken-in after all.

I noticed that the NAVI was auto-tunned to the old tires, after some 100 miles it seems that is auto-tunning to the new tires again. I felt that as if the indicated position is all time ahead of a turn or an exit. With time I guess the NAVI would auto-callibrate to the new tires. I suspect that reseting the NAVI after new tires could be recommended too.

No wet test so far but sure that would happen soon

Finally, you would strugle with PSI you should put in front and the rear. All 32PSI, 35 in the front, or all at 35 PSI? ....

I hope this helps.

More info to be posted tommorrow

Happy piloting



------------------
Black, Ebony, 3.2 CL Type-S, NAV.
- 3M clear bra, by Stonguard (full front bumper, and side mirrors, and partial hood)
- Acura Spoiler, Moonroof visor
- Splash guards, Winter mats, Trunk liner
- Valentine V1 Radar Locator
- HELMS Service Manual
- PIAA 19169 road lamps
- 03/19/01: Injen Polished CAI
- 04/13/01: 235/40/18 NITTO 555 on 18x7.5, +45 offset, Koing Imagine in Silver with wheels locks

EricL

"I never said thge higher the rolling resistance the better. On the contrary. But you, yourself, go to the link that Eric posted earlier in the thread and experiment with different sizes. You will see that the lower the number the worse it is. Put in any size you want and you will see that results are consistent."

I'm actually serious -- would you mind telling me something -- OK.

1. Please explain: "You will see that the lower the number the worse it is". "What number?"

I am going to just put in some numbers here and you can check them -- OK

Put in the OEM specs and we will use 1000 lbs -- OK?

Then put in the specs for a 239/45-17 (this is very close to the exact radius of the 215/50-17.

So, I get this:

With the stock tire with 215/50-17 with 1000 lbs Elastic = .0035 and speedo = 60 AND
the comparison tire with 239/45-17 with the same 1000 lbs, same Elastic = .0035 (speedo is at 60.009 -- that is close enough yes/no)

I get a Rolling resistance factor of 0.10088 for the stock 215/50 vs. 0.096 for the 239/45-17.

Then I get a Rolling Resistance factor of:
161.40 for the stock tire vs. 153.10 for the 239/45-17.

(Note: I used the 239 to insure that the unloaded rolling radius would be the same for both)

So, I get the 45 series having with a resistance of 153

And the stock with a resistance of 161.

So, isn't the rolling resistance (drag force) greater with a higher number.

If you had a coefficient of friction of 0.9, isn't that higher that a coefficient of friction of 0.8. If the friction is higher, isn't the resistance to movement higher?

If a given load is supported by the same area (supposition), but the support is in the "width", then doesn't that lessen the "front-rear" patch length.

If the front-rear patch length is reduced (accordingly), doesn't the tire not have to deform as much?

I actually called my friend who did a lot of work for Nissan racing and I said, OK, let me know if "I'm full of it" -- he verified what I said.

So, in the interest of all, would you comment?




------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

gavriil

The lower the rolling resistance the better. The way it is represented in that calculator of yours it is the oposite though. Have you not figured that out yet? Continue experimenting with the numbers and while keeping in mind that larger tires usually equal more resistance see the consistent results.

------------------
Gabriel
CL Type S

EricL

Time to go offline -- OK -- I'm going to email you OK.




------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

gavriil

which address do you see?

------------------
Gabriel
CL Type S

EricL

garviil1@yahoo.com <garviil1@yahoo.com>


------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

gavriil

That's it.

------------------
Gabriel
CL Type S

EricL

You have mail!




------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

EricL

Message from yahoo.com.
Unable to deliver message to the following address(es).

<garviil1@yahoo.com>

That is the 2nd try with instant failure.

------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

[This message has been edited by EricL (edited 04-15-2001).]

EricL

<pre>
<font size=+2>
Subject: failure delivery




Message from yahoo.com.
Unable to deliver message to the following address(es).

garviil1@yahoo.com:
216.136.129.18 failed after I sent the message.
Remote host said: 554 delivery error: dd This user doesn't have a
yahoo.com account (garviil1@yahoo.com) - mta450.mail.yahoo.com
</font>
</pre>

------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

[This message has been edited by EricL (edited 04-15-2001).]

[This message has been edited by EricL (edited 04-15-2001).]

EricL

I give up -- I tried sending 4 emails to your address and they all come back with a non-working address.

Then you disappear.

This really makes me wonder what the heck is going on. I was going to run through about 4 iterations. It is that low series profile tires like 40 series super wide tires have even less rolling resistance that 45, and 45 series have less than 50s. I even verified the javascript code in the calc to verify its proper operation.

It is easy to explain this way:

If you pushed on a 1" wide strip with 100 lbs, you would have 100 lbs / inch.

If you pushed on a 2" wide strip with 100 lbs, you would only have 50 lbs / inch.

So, as the tire widens up, the tire in not deformed as much. Since it now doesn't have to "deform" as much while rolling, it provides less resistance.

You can do it yourself by just using +1 size, +2 size, +3 size, etc. Each time there is less resistance.

------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

[This message has been edited by EricL (edited 04-15-2001).]

EricL

Well, I guess I should never reach out.

I'll give you the benefit of the doubt, let me know when you get your e-mail up and working again.

------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

FDao

Gabriel,

I tried to send you e-mail as well, but got an error.

Anyway, you did say that the "Higher the Rolling Resistance, the Better You Fool", verbatim. Unless I am reading it wrong?

------------------
Frank
01-S White/Parchment
Comptech Sways & Springs

Al Uminum

Hey, Guys?! Can't you take this sex stuff private?



------------------
"01" CL Type-S
White\Black
Comptech Springs
Comptech Sways
Navigation System
Burlwood Shifter
Guards+Fenderwell Trim
PIAA16969
Smokers Package
My Car

gavriil

THe correct spelling of my e-mail address is

gavriil1@yahoo.com

I did not disappear, it was Easter for some people this past Sunday and some people are hosting and hosting is work. Geee, I dont live here at acura-cl.

------------------
Gabriel
CL Type S

gavriil

I tried to send you e-mail as well, but got an error.

Anyway, you did say that the "Higher the Rolling Resistance, the Better You Fool", verbatim. Unless I am reading it wrong?

[/B][/QUOTE]


Go to the calculator and read it thoroughly. It says "Rolling Resistance Factor" not "Rolling Resistance". The higher the factor, the less the rolling resistance. It is that simple.

And for Eric: The lower the tire profile, the more the rolling resistance, the lower the RR factor. The reason for that is because although there is less tire as far as profile, the sidewalls are MUCH stiffer now which increases friction by a TON!

Another thing you should know is that 80% of a tire's drag in general (call it RR or friction) comes from its own internal friction forces NOT friction/RR created from it touching the ground/asphault. Which means that the issue of sizing and selection of compound is more important than ever.


------------------
Gabriel
CL Type S

EricL

1. I talked to Toyo and more tire folks about this. I asked if I could be missing something about "Rolling Resistance", etc.
They said Rolling Resistance is the same as a drag force. This means more gas mileage loss and if a the car was left to slow down from 20mph, the car with the lower RR would take longer to slow down (no wind, no brakes). I gave them the basic equation, and they said this was due to "deformation" issues related to tire footprint. The harder to deform the tire, the more energy is used, and the more the tire resists movement.



The Rolling Resistance Force ("original" or "new size" is correlated with the RRF (Rolling Resistance Factor). As RRF goes up, so does the Rolling Resistance Force.

The RRF is a product of the RRFactor and wieight and diameter. Hit "view-->Source" on your browser, and you can look at the equations yourself. (Don't take my word for it -- look for yourself [if you care/want to])

I know the calcs are correct on his page/link (in relation to the equation he has at the bottom of the page). HOWEVER, If you think the man's calculator is incorrect, he does post his e-mail address, so please e-mail him and tell him that it is not working correctly and/or his formula is not correct.

If you find out that he screwed up his equations, please e-mail him and I'm sure he will be most appreciative and change it. His main page is concerned with energy saving tires. I'm sure he would consider this very important *and* would change the calculator to your liking if you can explain to him about any errors he made.

Just try: "View -> Source" (in your browser) and all of the equations in JavaScript are there for your inspection.



See my comment/paragraph above. When I use the calc, the higher the RRF goes, so goes the rolling resistance shown on his calculator. (Ever single time I increase a factor that makes the RRF (rolling resistance factor) go up, the box in the calc with the rolling resistance force, goes up.


Here is the JavaScript from his calc:

f.RRF1.value = (f.RR1.value*(1-(-1*(f.speedometer.value/100)))*f.weight1.value);

The f.RRF1.value is the Rolling Resistance force AND will go up if the f.RR1.value (Rolling Resistance Factor) goes up. They are positively correlated.




The elastic coefficient actually GOES DOWN with a STIFFER SIDEWALL. Something LESS ELASTIC is STIFFER -- it has a lower elastic coefficient. (Example: if you have a rubber band -- it is very elastic, so the elastic coefficient goes up.) It is just like friction -- with more friction, you increase the coefficient of friction.)

If you go back to the calculator, you will see that as you reduce the "Elasticity Constant", this lowers the resistance. A stiffer sidewall makes for an even smaller contact patch in the front to rear direction, and thus reduces the deformation of the tire.

Think of it this way, if only the bottom 1" of the tire contacted the road, you would have a very slight angle between the curvature of the tire at the point of contact of the road. Now, if you have a softer sidewall, there is a saggy sidewall with a big long patch on the pavement. If you measured the angle between the tire's curve at the junction of the flat area and the tire's curve, you would find the angle is greater than the case of the stiff sidewall." If you bend a thick rubber strap, the more you deflect it, the more it resists -- it is just like the tire.

Example: Get a hardwood roller and press down on it and roll it back and forth. It rolls rather easy. The contact point at the bottom of the very rigid and stiff wood doesn't deform much at all at the bottom.

Now get some very soft Balsa Wood. If you roll it with a great deal of pressure, it will tend to deform at the contact patch with the rolling surface (it will have a flat like bottom as you roll it). So, it is softer material, but harder to roll with a lot of weight on it.




I don't know the exact percent of friction forces come from internal "stress".

In this area I can only say this:

The carcass, belt winding and construction are very important to reduce "squirming". This squirming will create a lot of heat, and heat is a product of energy. So, yes the inner construction is very important to keeping a tire from exploding. This is why a high speed rated tire will GENERALLY have a better constructed carcass than a low speed tire and will generated less heat at high speed. High speed with squirming can cause a tire's temp and air pressure to increase, causing the possible catastrophic failure of a tire. So a tire with low squirm (low internal friction) and strong construction is very important.

I'm glad you brought up this point. When tires are tested for speed, they are mounted on a jig and a big motor drives the tire on a couple of rollers (or roller) to simulate the deformation. Without the deformation with the road, the tire would not generate much heat.

So, the selection of the right materials is the billion dollar secret, and it is the interaction with the road (in the case of tires with speeds under 200mph) that determines the energy losses. If the tire doesn't contact "something" and doesn't deform, the tire test becomes a test to determine the max speed before it explodes due to too much centrifugal force.

A flywheel analogy would fit here.

I would appreciated it if you could cite a reference for our/my benefit regarding your assertion of centrifugal tensions creating more internal forces than the deformation issues (if that is what your are saying)



------------------
Silver 2001 CL-S with NAVI

• Mud guards
• Wheel locks
• Toyo T1S 235/45ZR17-97W* Proxies on 17x8" SSR Competition wheels (48lbs less than stock)
• Kevlar/SS Brake lines ordered
• Comptech headers & sways ready
• Silver AEM CAI ready
• 6 coats of Zaino magic

[This message has been edited by EricL (edited 04-17-2001).]