samh

Hi,

Last time I replaced tires on the stock 2004 TSX, I got the OEM Michelin Pilot MXM4s. Tread getting pretty shallow again, got a couple of sidewall goose eggs gestating and am considering trying Bridgestone Turanza Serenity tires (215/50R17 XL 95V).

Would the 3 extra lbs per tire (23->26lbs) make a noticeable difference in mpg. I assume the handling might be slightly less crisp as well.

Thanks for any info.

Sam

LuvMyTSX

There have been a few threads already discussing this. I'd search for them and do a little reading. Another choice is Bridgestone Pole Positions, also previously discussed.

vollum

Put the Turanza Serenitys on our 04 TSX this spring... Extremely quiet comparted to the OEMs....A little less road feel...Subsequently compensated somewhat by inflating one pound higher than the recommended 32 front and 30 rear. Impact on mileage still unknown...Mileage went down the first time I checked but I found that the tires were underinflated...30 front and 28 rear....Also my wife started driving the car a lot more and she has a much heavier foot than I do. I'm going to have to wait until we do a road trip to really determine the impact on mileage.

Itchytoe

I switched to Turanza Serenities from the stockies about 20,000 miles ago. They have a funny response time and feel till they're well broken in. Overall, much quiter, more comfortable, and they grip way better than stockies. I noticed no substantial change in MPG, but I run them at 35lbs all around, so at the factory setting, you may notice a small loss since they're softer and stickier than stock.

ofusball21

I am also looking to replace my stocks on my 04. I am looking at both the Serenities and the Pole positions. I read the descriptions on tire rack but my main concern is a quieter less harsh ride and obviously more grip. I live in NJ and we have terrible roads with 4 seasons of weather so I need a good all season.

Luvmytx I know you have the Poles and have been happy with them and you also live in NJ so I was wondering if you could let me know how they handle in the winter as well as road noise compared to stocks. Thanks I appreciate it.

samh

Thanks for the comments. I actually stopped into a Firestone shop on the way to work the other day (wasn't sure if it's just a franchised name, but thought maybe since Bridgestone bought Firestone tires I'd find out something new).

The counterman said the Turanza Serenity is a great Grand Touring All Season tire, but that I should also consider the Potenza G 019 GRID High Performance All-Season. I didn't really care about the agressive-looking tread pattern and wasn't swayed by his "I run them on my own Lexus" sales line, as much as "buy 3 @ $150 get 1 free" and the fact that they were in stock and the Serenitys weren't - and mostly since after parking at the store, I noticed my sidewall deeply cracking over one of the goose eggs ...

There was a mall with WiFi next-door, so I checked a few reviews (ex. http://www.tirerack.com/tires/tests/...y.jsp?ttid=108 ) on my laptop, and decided to give them a try. (They have a 30 day if you don't like the tires warranty, too.)

They are directional tires, so I guess I'll have to be more on top of regular rotations (back to front only, I suppose, unless I have them unmounted and remounted). After sitting at work few hours later in the day, I checked and saw they were over-inflated by a couple of psi - but I figure on giving things a few days to settle before going to TSX recommended 32/30.

I put on ~ 3-400 miles/week, so I'll probably update about the mpg, etc., after a few weeks of riding.

Sam

PS These are fairly newly released tires. I wasn't too sure about the long-term usefulness of the user opinions for any of the tires I'd been considering. If I recall correctly, the TireRack reviews all only covered ~ 1.5 million reported miles each for the Turanza Serenity and Michelin Primacy MXV4, as well as the Potenza G 019 GRID I got, whereas the OEM Michelin Pilot MXM4s totaled ~ 35+ million miles.

LuvMyTSX

I really like the Poles, but I also change to snow tires come November. The Poles do fine for a couple of inches of snow, but I really prefer my snows for anything deeper. I've found, though, that it's like that for pretty much any all season tire (obviously). They are ok, but not great in the white stuff.

Tangoman

Extra weight in your driveline only affects acceleration/braking times. If you do a lot of highway driving, your MPG is really defined by your steady state rolling resistance. This has more to do with the rolling resistance coefficient of your tires, and not the actual weight of the tires/wheels. In other words, extra driveline weight only effects the MPG you get while you reach your cruising speed (in the form of slower acceleration times).

If you do a lot of driving in the city, and you accelerate hard, extra mass on your driveline effects you more. You really have to do tests to figure out how much (as it is completely variable upon your driving style). Keep in mind that driveline weight effects your braking performance as well.

samh

Very interesting re: mpg from the engineering viewpoint. Thanks. More complex that I first thought, real-world friction more important than tire mass (or radius). Wonder exactly how they do those EPA mpg tests...

Tangoman

No problem. If you want to know more about it, try out this site (check out the terms in the formulas)

http://thecartech.com/subjects/auto_...e_formulas.htm

Rolling resistance is what affects you the most while you are holding a speed.
Inertial resistance is what comes into play when you change velocity (acceleration/braking).

As you can see in the RR equation, only the mass of the car and the friction of the surface (which is made up of the surface and the tires) define how much roll resistance you have.
On the other hand, your inertial resistance does include a rotating mass term. Increasing this term does increase your total inertial resistance, but as you can see this only comes into play when you are changing speeds.

NOTE: While doing calculations the other day I realized something interesting (maybe only interesting to me). Change in grade angle (going uphill or downhill) affects your gas mileage a great deal. If you go from a 0 degree surface to a 1 degree surface uphill, the added gradient resistance is almost equal to that of your rolling resistance. In other words, going slightly uphill can cut your gas mileage in half (theoretically of course). In real world driving you are constantly going uphill and downhill, so you don't notice.

Sorry for the long responses, but I like to be thorough.
I do know that some tires (specifically some Yokos) have some pretty high rolling resistance, and some TSX drivers have experienced a drop of MPG of up to 20 percent. If you search the forums, you will find out exactly which tires have this issue.

Now you know why Goodyear puts "ultra low rolling resistance tires" on the Prius.

samh

Thanks for taking the time to flesh this out and the formula link. You set me searching, and I found all sorts of interesting tidbits on rolling and inertial resistance.

------

For those looking for reviews other than Tire-Rack, I noticed that the November issue of Consumer Reports will have results on 69 all-season and winter tires (tested at P215/60R16 size) - including most mentioned in this thread.

Performance all-season tires (V-rated)

Bridgestone Turanza Serenity
Continental ContiProContact
General Altimax HP
Toyo Versado LX
Goodyear Eagle ResponseEdge
Kumho Ectsa LX Platinum
Hankook Optimo H418
Bridgestone Potenza G019 Grid
Dunlop Signature
Firestone Firehawk GTv
Fuzion VRi
Goodyear Eagle GT
Pirelli P6 Four Seasons
Michelin Pilot Exalto A/S
Yokohama Avid V4s

Performance all-season tires (H-rated)

Continental ContiProContact
Cooper CS4 Touring
General Altimax HP
Michelin Primacy MXV4
Hankook Optimo H418
Nokian WR G2
Goodyear Assurance Fuel Max
Falken Ziex ZE512
Falken Ziex ZE912
Fuzion HRi
Pirelli P6 Four Seasons
Kumho Solus KH16
Michelin Pilot Exalto A/S
Yokohama Avid H4s


Standard all-season tires (T-rated)

BFGoodrich Traction T/A
Bridgestone Turanza EL400
Cooper CS4 Touring
Cooper Lifeliner GLS
Dunlop SP 60
Falken Sincera SN828
Firestone FR710
General Altimax RT
Goodyear Assurance TripleTred
Hankook Optimo H727
Dayton Quadra LE
Kumho Solus KR21
Maxxis Escapade MA-T1
Michelin HydroEdge
Pirelli P4 Four Seasons
Pirelli Cinturato P5
Sumitomo HTR T4
Toyo Versado LX
Toyo Extensa A/S
Yokohama Avid T4
Yokohama Avid TRZ
Yokohama Avid Touring-S
Uniroyal Tiger Paw Tour SR


Winter tires (Q, R, S, T rated)

Bridgestone Blizzak WS60
Continental ExtremeWinterContact
Cooper Weather-Master S/T 2
Dunlop Graspic DS-2
Firestone Winterforce
General Altimax Arctic
Goodyear Ultra Grip Ice
Hankook Winter i*Pike
Michelin X-Ice XI 2
Toyo Observe G-02 Plus
Yokohama ice Guard iG20
Gislaved Nordfrost 5
Nokian Hakkapeliitta 5
Nokian Hakkapeliitta R

Winter tires (H-rated)

Hankook icebear W300
Pirelli Sottozero 210 Series II
Michelin Primacy Alpin PA3

Itchytoe

Doesn't your signature say you're a mechanical engineer? Hmm, wish I could quote sigs too.
If you were a mechanical engineer you'd know how full of BS that is. If you were a mechanical engineer you'd know that it takes more energy to keep a heavier mass rotating than it takes to keep a lighter mass rotating at exactly the same speed. If you were a mechanical engineer, you'd know that lighter drivetrain components reduce the amount of drivetrain loss thereby netting higher HP to ground numbers. If you were a mechanical engineer, you'd know that your engine has to produce less power because of that to keep you rolling down the road at the same rate (meaning same power to ground with less engine output). If you were a mechanical engineer you'd know that your engine burns less fuel when it produces less power. If you have a brain you'd know that burning less fuel yeilds better fuel economy.

A lighter drivetrain, including your wheels and tires, will get you better fuel economy with all other factors equal. Obviously if you get get lighter wheels but high rolling resistance tires, you're not going to see the same gains. Most performance upgrades will also get you better fuel economy if you don't let the performance upgrades change your driving habits. More performance potential doesn't yield lower fuel ecnomy and lighter wheels and tires help both.

Tangoman

Um, notice this quote from my post about "Rolling resistance is what affects you the most while you are holding a speed. " It affects you MOST when holding a speed, I didn't say that inertial resistance didn't affect you at all... so it seems you have misunderstood me, so let me explain.

If you add 3 lbs to each tire right now (which was the original post) and you drive on the highway, maintaining a speed, you likely will see no measurable difference in gas mileage. I never said it didn't affect your mileage, but as an ENGINEER I know when to neglect things that don't make any difference. If I didn't, I couldn't do my job. NOW - with that being said, if you added that weight and did 1/4 mile times, ABSOLUTELY it would matter, I completely agree. No one would want to do that, less power, slower accelerations, the whole deal (everything you said). This is because the main resistance your car has to overcome when accelerating is INERTIAL resistance, not rolling, and not air.

I never said adding driveline weight wouldn't decrease horsepower, and therefore increase fuel consumption. I completely agree with your last statement, but I disagree that this guy should choose different tires if his driving style doesn't require it.

If we were arguing on whether increasing the tire mass decreases gas mileage, why would anyone in their right mind disagree with you? I certainly wouldn't disagree, but we aren't talking about that, we are talking about if it matters to him. In this case, he might get 30.2 mph instead of 30.4 (and I challenge anyone to show me mileage numbers tank after tank that don't vary by 1-2 mph already). If the difference is within the standard deviation, then he likely won't care.

By the way, I like more horsepower, which is why I have UR pulleys just like you And when I bought them, I didn't see any noticeable MPG change during highway driving, only when I drove in the city, accelerating from stoplight to stoplight.

Tangoman

Oh, forgot to add something. The reason why people see mileage increases with rotating mass reducing parts is because people do accelerate when they drive their cars... They don't always drive on the highway. Maybe I just got too theoretical with it, and that is where the misunderstanding came from.

If he believes that he isn't on the highway enough, and that he could benefit from lighter tires, then he should try to save rotating mass - I wanted to let him decide, on the off chance that perhaps saving 20 bucks a tire now is more important to him than saving 20 bucks on gas over the next year.

Itchytoe

UR pulleys alone got me about 8% better economy on my normal weekly drive which includes 750 highway miles and probably 30 non-highway miles. You're not trying to say 8% lower fuel consumption on 780 miles is based purely on 30 of those miles? That's what? 100 MPG for those 30 miles to see those kinds of gains? UR pulleys reduce weight, but they also underdrive all of your components, which saves you a ton of energy. If you didn't see any fuel savings with your UR pulleys, it's because you like the extra power a little too much and should get the lead out of your shoes.

Check out any of the cleanmpg com or similar sites about real people's ways to safe fuel and you'll see that lighter wheel/tire combos are a great help. They don't just affect acceleration and anyone who tells you they do doesn't know what they're talking about. As it turns out, lighter tires have a bigger impact on your fuel savings than lighter wheels because of the location of the weight. The further you move the center of the weight, the more energy it takes. Lighter tires move the center of weight closer to the hub, making the center of weight move less distance due to the smaller radius. (No I don't mean smaller physical tire radius. I mean a smaller radius from the center of rotation to the center of weight.)

earbuckle

I'm not sure I buy your analysis, Itchytoe. Tangoman is stating the facts accurately. As a registered professional engineer, I don't know what you mean by "center of weight." By definition, the "center of weight" would seem to coincide with the axis of rotation. That's sort of why tires/wheels are balanced. You may be confusing "weight" with inertia, which are two entirely different things. A heavier wheel/tire combination will exhibit greater inertia, which takes more energy to accelerate (or rotate faster) and it also takes more energy to decelerate (or stop). But driving at a steady state (say 65 MPH), the difference of a few pounds of weight is totally swamped by the rolling resistance of the tire itself. That's one of the reasons Michelin's most efficient (i.e. low rolling resistance) tires bear the Green-X.

You might also engender a little more respect for your views if you didn't come across as a smart-alecky kid. Just my two cents.

Anecdotal experience sometimes coincides with underlying physics, but not always.

Have a nice day.

earbuckle

This is patently false! It takes exactly the same energy to keep any mass rotating (Newton's Laws of Motion). The reason it "seems" to take more energy for a heavier mass is that ALL the energy required to keep a mass rotating is due to external losses. That is, frictional losses of bearings, air resistance (more if a rotating mass is a fan blade than if it is a flat disk), etc. A spinning mass on magnetic (~frictionless) bearings in a vacuum (no air resistance) requires very little energy input, regardless of mass or "weight."

To accelerate the mass, more energy input is required for a larger mass. Think Force=mass x acceleration.

Itchytoe

Fortunately, we're talking about rotating a wheel and tire on a vehicle moving down the road, not an object in a perfect, frictionless environment. You've misused Newtonian physics like most people do. As a registered professional engineer, you should be ashamed. You should also know that it takes exactly no energy to keep a mass spinning in a perfect frictionless environment because it isn't losing any energy by definition of the frictionless environment you set up. You should also know that it takes more energy to move more mass in this frictionless environment by the formula you provided, F=MA. It takes way more energy to rotate the Earth in space, which is basically your high mass object in a frictionless environment, than it takes to rotate any wheel in the vaccuum of space. Really, you should have learned that back in physics 101. How do you pass the PE exam and not have a death grip in such a simple concept?

I'll explain why lighter wheels yeild better fuel economy on the highway and will use your beloved F=MA to do it. To know why lighter is better on the highway, you have to know a little bit about vectors, which our mechanical engineer friends know very well after the school they have been through. Drag and rolling resistance collectively (and individually) produce a force accelerating you in the backwards direction. (Yea accelerating you backwards, not decelerating you. Look up the definition as it pertains to physics of acceleration and you'll know why.) In order to maintain a constant speed, you have to accelerate in the forward direction with a force equal to the force accelerating you in the backwards direction. That "cancels out" drag and rolling resistance and all other forms of resistance so that you can keep rolling down the road. Whoa! Wait a minute! I just said you have to accelerate to maintain a constant speed! Seems absurd? Of course not, and you all already know why. Because if you didn't accelerate i.e. burn fuel to add energy to your wheels, you'd stop because of resistance. Turn your car off while driving down the road and see for yourself. Ok don't really do that, just think about what would happen if you did. You're constantly adding energy to your wheels, and accelerating them to keep a steady speed.

Force = mass(acceleration). Acceleration is constant for a constant speed for the most part. More force for more weight (which is really just mass(pull of gravity at the current location) so think of them interchangeably for this explination if you like) and less force for less weight. Less force yeilds less fuel consumption, and more force yeilds more fuel consumption.

Understood anecdotal experience always coincides with underlying physics. Bear in mind, the experience and the physics are often misunderstood.

Have a nice day.

samh

Currently at about 3000 miles, the Potenza G 019 GRID High Performance All-Season tires seem to have been a good value at the B3G1 price.

As mentioned above, the installer did over-inflate the tires by about 3 psi, leading to a "floating" feeling to the ride. Even so, handling and braking were fine. After bringing them down to the Acura recommended 32/30, the road feel improved significantly and mileage increased. The ride overall is somewhat less harsh than with the old stock Michelins. Also noticed less tire "chirps" or slips than the stock Michelins (even when they were new) under various circumstances.

Performance in rain, snow and sleet has been fine, even a bit more sure than the stock Michelins. It's hard to remember exactly how the Michelins performed when new, but ABS and VSA seem to engage less in comparison.

Don't have a more accurate GPS baseline mileage for comparison, but so far, Navi-reported mpg is down about 5% for my driving mix - relative to the near-balding stock Michelins. See the technical discussions above for possible reasons intrinsic to the new heavier tires, or simply the increased diameter (due to the full tread/fewer revolutions recorded per unit distance traveled, etc.). I haven't seen a 5% increase in fuel costs.

FWIW, A second driver on the same vehicle who's much more prone to parallel-parking curb rash incidents than I, claims the Bridgestones are less likely to scuff (either tires or rims).