1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Wider tires improve Prius handling and looks

Discussion in 'Gen 2 Prius Main Forum' started by nyprius, May 24, 2006.

Page 1 of 3
  1. nyprius

    nyprius Member

    Joined:
    Oct 8, 2005
    385
    24
    0
    Location:
    Saratoga Springs, NY
    Vehicle:
    2005 Prius
    I'd like to put 195/60R15 tires on my 05 BC Prius. The US 185/65R15 OEM tire looks narrow on the car and doesn't seem to handle well (poor cornering, freeway tracking, etc). The wider 195 tire would handle better and look better. In Japan, Europe and Australia, the OEM Prius tire is a 195. Australia uses a 195/60R15. Japan and Europe use a 195/55R16, but I don't want to buy new rims. The 195/60R15 has 5-8 more revolutions per mile (depending on tire brand). This would affect the speedometer reading by less than 1%. Is there a way to re-calibrate the speedometer/odometer for new tires?

    In an earlier post, someone said re-calibration could be done. But I could not find re-calibration info on PC.
     
    #1 nyprius, May 24, 2006
  2. DocVijay

    DocVijay Active Member

    Joined:
    Sep 15, 2005
    1,455
    2
    0
    Location:
    Tampa, FL
    If the difference is less than 1% you don't need to recalibrate. It is close enough.
     
    #2 DocVijay, May 24, 2006
  3. LowCO2

    LowCO2 New Member

    Joined:
    May 23, 2006
    51
    0
    0
    <div class='quotetop'>QUOTE(nyprius @ May 24 2006, 08:00 AM) [snapback]260266[/snapback]</div>
    Not sure how 1 extra cm of rubber is going to look much or handle much better. I bought my Prius cleaner transportation / mpg biased performance - most people that are concerned with "looks" or "handling" might opt for something less..
     
    #3 LowCO2, May 24, 2006
  4. usbseawolf2000

    usbseawolf2000 HSD PhD

    Joined:
    Sep 22, 2004
    14,487
    2,997
    0
    Location:
    Fort Lee, NJ
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    Just want to point out that the difference is 10 cm... not 1cm.

    Dennis
     
    #4 usbseawolf2000, May 24, 2006
  5. ceric

    ceric New Member

    Joined:
    Oct 30, 2004
    1,114
    53
    0
    Location:
    Fremont, CA
    Vehicle:
    2005 Prius
    Dennis,
    195mm - 185mm = 10mm = 1cm
     
    #5 ceric, May 24, 2006
  6. B Rad

    B Rad New Member

    Joined:
    May 18, 2006
    295
    1
    0
    <div class='quotetop'>QUOTE(LowCO2 @ May 24 2006, 10:29 AM) [snapback]260329[/snapback]</div>
    They put larger wheels (16in) on the EUROPEAN Prius and it sure looks a lot better. I see no reason why a person can't be concerned with "looks" or "handling" and still want a Prius. My stock wheels and tires will be up for sale on E-Bay shortly after I take delivery.
     
    #6 B Rad, May 24, 2006
  7. nyprius

    nyprius Member

    Joined:
    Oct 8, 2005
    385
    24
    0
    Location:
    Saratoga Springs, NY
    Vehicle:
    2005 Prius
    1 cm = about .4 inches. That is noticable. The Prius weights nearly 3,000 pounds. That's fairly heavy for narrow tires. Weight plus narrow tires equals poor cornering and highway instability. That's probably why nearly every other country, including the one where the car was designed and built, uses a wider 195 rather than 185 tire.

    As others have said, the US Prius has some better and some worse features than other countries. The narrower tires and rear drum brakes are examples of worse features. The narrow tire problems can be easily remedied. The 6 inch rims on the US Prius can easily handle 195 tires. And the speedometer impact is neglible, as pointed out above (though it would be nice if the speedometer could be calibrated so there was no impact).

    I think the Prius is great. I'll never own a non-hybrid again (unless something better comes along). I don't think there's anything wrong with having the Prius look sporty, as someone implied above. The wider tires will make the car look better and handle better.
     
    #7 nyprius, May 24, 2006
  8. usbseawolf2000

    usbseawolf2000 HSD PhD

    Joined:
    Sep 22, 2004
    14,487
    2,997
    0
    Location:
    Fort Lee, NJ
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    <div class='quotetop'>QUOTE(ceric @ May 24 2006, 11:34 AM) [snapback]260331[/snapback]</div>
    Thank you. :D My Celica that weighted 2,450 lbs had 195 mm wheels. I can tell the difference.


    Dennis
     
    #8 usbseawolf2000, May 24, 2006
  9. hycamguy07

    hycamguy07 New Member

    Joined:
    Feb 18, 2006
    2,707
    3
    0
    Location:
    Central Florida
    Vehicle:
    2007 Prius
    <div class='quotetop'>QUOTE(nyprius @ May 24 2006, 09:00 AM) [snapback]260266[/snapback]</div>
    I have this size on my car 195/60R15 using the stock rims looks sporty.. :rolleyes:

    It did seem to lower my mpgs on the screen though.. :unsure:

    I would love to get a set of raised white letter tires for my prius!!! :D
     
    #9 hycamguy07, May 24, 2006
  10. auricchio

    auricchio Member

    Joined:
    Mar 31, 2006
    921
    7
    0
    Location:
    Cambria, CA, USA
    Vehicle:
    2006 Prius
    It's possible that in non-US countries the larger tire is easier to find and cheaper. That's a simple explanation.

    As for more revs per mile, that will make the speedometer error worse. With OEM tires, the speedo reads high. When it says 60 you're going about 59. So with a faster-revving tire, the speedo will be even farther off. If possible, you'd want to choose fewer revs per mile.
     
    #10 auricchio, May 24, 2006
  11. nyprius

    nyprius Member

    Joined:
    Oct 8, 2005
    385
    24
    0
    Location:
    Saratoga Springs, NY
    Vehicle:
    2005 Prius
    Everything is easy to find in the US. But I agree, cost is probably a major reason the cheaper 185 was put on US Prius's.

    Why do you say the OEM 185/65R15 tires makes the speedometer over-read? You'd think the OEM tire would be in synch with the speedometer.
     
    #11 nyprius, May 24, 2006
  12. auricchio

    auricchio Member

    Joined:
    Mar 31, 2006
    921
    7
    0
    Location:
    Cambria, CA, USA
    Vehicle:
    2006 Prius
    People's experience is that the speedometer reads a tad higher than actual.
     
    #12 auricchio, May 24, 2006
  13. KMO

    KMO Senior Member

    Joined:
    Apr 15, 2004
    1,539
    421
    0
    Location:
    Finland
    Vehicle:
    2023 Prius Prime
    Model:
    N/A
    The two standard Prius tyre types (185/65R15 and 195/55R16) have practically identical outer diameter, so I doubt the speedometer is calibrated differently for them.

    In Japan (and possibly other Far East/Australasian countries), the Prius is offered with both wheel types, depending on the trim level.

    195/55R16 tyres are actually rather expensive. It's a pet whinge of some on Yahoo Prius-UK. On blackcircles.com, they range from £60 to £92 (the standard Bridgestone ER30 = £71), compared to a range of £21-£93 for 185/65R15, most being £40-55.

    That's because 185/65R15 is quite common for all sorts of standard cars, whereas 195/55R16 is rare, typically seen on performance versions of some cars, and some BMW-type things. No-one makes cheap tyres in that size, and you have a limited selection.
     
    #13 KMO, May 24, 2006
  14. kDB

    kDB New Member

    Joined:
    Jun 22, 2005
    241
    0
    0
    Location:
    Fenton, MO
    <div class='quotetop'>QUOTE(LowCO2 @ May 24 2006, 10:29 AM) [snapback]260329[/snapback]</div>
    your looking at it wrong. sure it's only 1cm wider, but... there is more than 1cm that touches the ground due to that. and on four tires.

    for example, let's say the tires touch the ground 185 and 195 wide, but both at 185 front-to-back. that's 342.25cm² for the 185, and 360.75cm² for the 195, each tire. total: 1369cm² vs. 1443cm²

    now if i've done my math correctly, that's a difference of ~5.5% more tire tread touching the ground. that is a big enough size difference to cause a noticeable effect.
     
    #14 kDB, May 24, 2006
  15. nyprius

    nyprius Member

    Joined:
    Oct 8, 2005
    385
    24
    0
    Location:
    Saratoga Springs, NY
    Vehicle:
    2005 Prius
    The 195/55R16 may be rare and expensive as you say, but the 195/60R15 is as common as the 185/65R15. It's the OEM size in Australia. It's also a good compromise because you get the better looks and handling of the wider tire without having to change rims or pay much more.

    I'm going to replace my OEM Integrities soon because they are terrible in the snow and on the highway. I'll definitely use the 195/60R15 size. I'm just not sure which tire yet. Toyo TPTs and 800s look good. I originally liked the TripleTred, but I hear it's not that good in the snow. There are much better high performance all season tires. Any suggestions?
     
    #15 nyprius, May 25, 2006
  16. tmorrowus

    tmorrowus Member

    Joined:
    Dec 30, 2003
    514
    15
    2
    I doubt you would notice much handling improvement... the Michelin Hydroedge tires are actually narrower than other tires, yet they get high marks for handling.
     
    #16 tmorrowus, May 25, 2006
  17. priusenvy

    priusenvy Senior Member

    Joined:
    Mar 15, 2004
    1,765
    14
    0
    Location:
    Silicon Valley, CA
    Vehicle:
    2005 Prius
    <div class='quotetop'>QUOTE(kDB @ May 24 2006, 04:29 PM) [snapback]260593[/snapback]</div>
    Why do you even introduce length of contact patch??? (195 / 185) - 1.0 = 5.41%. Multiplying each width by a constant does not change this. I'm pretty sure this concept is taught by the 6th grade these days.

    Besides, area of contact patch is mainly a function of tire pressure and the weight it is supporting. All other things equal, the wider tire will have the same size contact patch as the narrower tire, but it will be wider and shorter (measured front to back). The wider, shorter contact patch usually contributes to better handling because force (pressure) is distributed more evenly across the contact patch during cornering compared to the narrower tire. Other contributing factors to subjective and objective improvements in handling are shorter, stiffer sidewalls and stickier tire compounds. And due to some physical interlocking between the tire and road, friction isn't completely independent of area and dependent only on normal force, as it is in the model of friction taught in high school.
     
    #17 priusenvy, May 25, 2006
  18. LowCO2

    LowCO2 New Member

    Joined:
    May 23, 2006
    51
    0
    0
    <div class='quotetop'>QUOTE(usbseawolf2000 @ May 24 2006, 11:49 AM) [snapback]260387[/snapback]</div>
    I had 295mm 19" wheels on my mercedes, and while they looked "cool" and handled "awesome", I'm now thinking cool and awesome are more about slowing down global warming, and leaving the quick handling in turns to those Mustang/Camaro NASCAR types, and there's always Viagra, if that troubles you.. :eek:
     
    #18 LowCO2, May 25, 2006
  19. LowCO2

    LowCO2 New Member

    Joined:
    May 23, 2006
    51
    0
    0
    <div class='quotetop'>QUOTE(B Rad @ May 24 2006, 10:38 AM) [snapback]260335[/snapback]</div>
    Make sure those 16" wheels are chrome (for looks) - maybe we'll see your Prius on PIMP MY RIDE someday.. :p
     
    #19 LowCO2, May 25, 2006
  20. hycamguy07

    hycamguy07 New Member

    Joined:
    Feb 18, 2006
    2,707
    3
    0
    Location:
    Central Florida
    Vehicle:
    2007 Prius
    I sure wish they made raised white letter tires for my prius...... :( :angry: :( -_-

    Then my wife could scuff those too :angry: :( :mellow:
     
    #20 hycamguy07, May 25, 2006
(You must log in or sign up to post here.)
Page 1 of 3