Tire Upgrade

<div class='quotetop'>QUOTE(Three60guy @ Jun 28 2006, 11:19 AM) [snapback]278138[/snapback]</div>

This is the exact example of comparing tires across classes using subjective opinions when the variety and number of tires the reviewer has actually experienced and tested is unknown.

Our example: conservative drivers would rate the Prius handling a 7-8 versus a performance driver's 4-5 due to the difference in experience and demand. A conservative driver's harsh and noisy, is a performance driver's responsive and quiet feedback.

The only accurate rating system is head-to-head testing by the same person (with instrumentation if possible), although TireRack's "surveys" could be still used to hint of what overall the tire performance is.

 

<div class='quotetop'>QUOTE(Three60guy @ Jun 28 2006, 02:19 PM) [snapback]278138[/snapback]</div>

Thanks! This is what i've been looking for.

 

<div class='quotetop'>QUOTE(NuShrike @ Jun 28 2006, 02:06 PM) [snapback]278159[/snapback]</div>

I am not in disagreement with you. However, good luck finding what you are looking for. I offered this spreadsheet as the best I could find. Nothing else. Given that ANY opinions on this subject are subjective even if it is only one person doing the ratings one could argue that such a system would also be imperfect. Alas we all live in an inperfect world. At least someone here on PriusChat went to the trouble of gathering all of the data and put it in one place. I thought that was awesome.

If you find what you are looking for I will be the first to congratulate you. I hope you do. Until then I hope the spreadsheet narrows down some of the variables.

Cheers

 

[When I looked on PC for tire recommendations, many tires were suggested, but three seemed to be recommended the most – Michelin Hydroedge (HE), Goodyear Comfortred (CT) and Goodyear Tripletred (TT). The TT was rated the best all season passenger car tire by Consumer Reports and Tirerack.

Just a note:
On my former car, I put about 65,000 miles on a set of HE, and I loved them. Rain/Snow/Dry: all were handled exceptionally...never hydroplaned once even on rutted flooded highways. They still looked good when I traded it. I'll probably buy a set when my Prius comes in.

 

<div class='quotetop'>QUOTE(nyprius @ Jun 28 2006, 10:02 PM) [snapback]277983[/snapback]</div>

We have four packages in Japan.

Code:

package              tire size  10-15 mode test
===================  =========  ===============
S                    185/65R15      35.5 km/L
G                    185/65R15      33.0 km/L
S Touring Selection  195/55R16      30.0 km/L
G Touring Selection  195/55R16      30.0 km/L

What do you mean the better tires?

My Prius is "G Touring Selection" and I replaced tires with 185/65R15.
They are comfortable, silent, smooth, light, better mileage and etc.
For me, the 185 tires are better than 195.

Also, what do you mean the rear disc brakes are better?
My feeling is the rear drum brake is light, inexpensive, simple, enough brake power and etc.
For me, the rear drum brake is better than disc for Prius.

Ken@Japan

 

In Japan, Prius comes with Goodyear GT3 comfort type of 185 tires.
http://eu.goodyear.com/uk_en/tires/repository/GT3/index.jsp

I know Prius in the US comes with Goodyear Integrity all-season tires.
Is it mandatory to have the all-saeson tires for new vehicle in the US?

Ken@Japan

 

Tests are rarely done between classes of tires. Heres the closest I could find to a test comparing a highly rated all-season passenger tire with all-season performance tires.

Here's a test comparing a Hydroedge with an Goodyear Eagle RS-A:
http://www.tirerack.com/tires/tests/pass_tires_wet_c.jsp

Here's a similar test comparing performance tires available in our size (including the BF Goodring Tration TA (H series), Bridgestone RE950 (discontinued - being replacend by the RE960AS), and the Dunlop SP Sport A2 (discontinued - replaced by the A2 Plus)) with the same Goodyear RS-A:
http://www.tirerack.com/tires/tests/traction_advantage_c.jsp

In the past, Consumer Reports tested some tires against multiple classes facilitating cross class comparisons. For instance, they tested the Michelin Energy MXV4 against performance tires and touring tires. I wonder what tire class they'll test this November.

 

<div class='quotetop'>QUOTE(nyprius @ Jun 28 2006, 09:06 PM) [snapback]278343[/snapback]</div>

... , reduced vehicle emissions, better hydroplaning resistance, arguably improved snow traction, lower cost, and softer ride if comparing a 185/65r15 with a 195/55r16.

 

<div class='quotetop'>QUOTE(ken1784 @ Jun 28 2006, 08:17 PM) [snapback]278318[/snapback]</div>

Some new performance cars are sold with only summer tires in the US.

These include the Civic Si, Mazdaspeed Mazda6 and Mx-5, Audi RS4, Ford Focus SVT, BMW M3, M5, and M convertible.

 

<div class='quotetop'>QUOTE(theorist @ Jun 28 2006, 09:18 PM) [snapback]278359[/snapback]</div>

Let's talk about cost. 185mm tire is less expensive than 195mm. Ok, but you are getting more rubber to hold the car weight. Would 195mm or 205mm tire last longer (provided, the same material)? If wider tire last longer, the cost could be a wash. Just a thought.

Dennis

 

<div class='quotetop'>QUOTE(nyprius @ Jun 28 2006, 09:43 PM) [snapback]278384[/snapback]</div>

I thought you and Ken were comparing size 185/65-15 with 195/55-16, which have limited choices and high prices in the US.

BTW, I switched to Continental ContiProContacts in a size 195/65-15 two weeks ago.

Comparing these with the Dunlop SP Sport A2 Plus tires size 185/65-15 that I was using, the larger, softer ContiProContacts are:
lighter
providing better fuel efficiency
worse handling, especially steering response
giving more accurate odometer and speedometer readings (according to GPS and highway marker comparisons)
smoother riding at equal pressures

I believe this shows the importance of tire design. The Dunlop SP Sport A2 Plus has a _much_ firmer sidewall and a thick continuous center rib in the tread. The ContiProContact sidewall is flimsy in this size (which weighs less than the ContiProContact in the smaller 185/65-15 size. :huh: )

I switched to the ContiProContact largely based on cars that use it including the VW Golf and Jetta TDI in this size and the VW GTI, Audi A4, A6, some BMWs, Jaguars, and Mercedes in other sizes. Still, I miss the superior handling and tracking of the smaller but firmer Dunlop SP Sport A2 Plus tires.

The no-no 195/65-15 size has improved my speedometer and odometer accuracy and has not caused any rubbing anywhere in the wheel wells.

 

<div class='quotetop'>QUOTE(theorist @ Jun 28 2006, 06:11 PM) [snapback]278353[/snapback]</div>

So, from your links let's make up a test of the Goodyear Eagle RS-A vs Michelin HydroEdge vs Dunlop SP Sport A2.
http://www.tirerack.com/tires/tests/pass_tires_wet_c.jsp
http://www.tirerack.com/tires/tests/traction_advantage_c.jsp

I'm going to use the individual performance drive data since the overall numbers don't make sense in HE vs SP2.

columns: RSA, HE, SP2 __(winner)

Dry Track (higher):
cornering stability: 6.08 6.05 6.18 __(sp2)
steering response: 5.94 6.25 6.36 __(sp2)
braking modulation: 5.87 6.38 6.47 __(sp2)
handling predictability: 5.77 6.29 6.24 __(he)
overall: 5.92 6.29 6.31 __(sp2)

Wet Track (higher):
cornering stability: 6.23 6.02 6.19 __(rsa, sp2, he)
steering response: 6.11 6.01 6.29 __(sp2)
braking modulation: 5.96 5.91 6.38 __(sp2)
handling predictability: 5.98 5.96 6.13 __(sp2)
overall: 6.07 5.98 6.25 __(sp2)

Braking Distance (lower):
dry: 96.6/98.7 93.8 91.9normalized to RSA's first 96.6 feet, this should be 89.8) __(sp2)
wet: 105.2/107.2 105.0 100.0normalized -> 98) __(sp2)

Average Cornering (higher):
dry: 0.89/0.92 0.90 0.93normalized -> 0.90) __(he/sp2)
wet: 0.77 0.73 0.76 __(rsa, sp2, he) Hydroedge is horrible in wet cornering?

"Under wet conditions, the Eagle RS-A posted the highest level of cornering traction (Average Lateral G's) and the fastest average lap time of the group. Not a surprise, considering even an average performer in High Performance All-Season category handles better than tires from a lower performance level category."

Varying times (drivers?) make slalom and lap time comparisons difficult.
but... :
Slalom Time (lower):
dry: 4.30/4.25 4.32 4.27normalized -> 4.32) __(rsa, he/sp2)
wet: 4.81/4.72 4.75 4.74normalized -> 4.77) __(he)

Lap Time (lower)
dry: 30.98/30.71 30.80 30.63normalized -> 30.90) __(he)
wet: 33.69/33.62 33.73 33.42normalized -> 33.49) __(sp2)

So, the overall winner here is Dunlop SP2 sometimes by a wide margin especially in wet. The hydroedge seems to outperform sometimes however in dry and the wet slalom.

Now compared to the survey results:
HE:
hydroplaning: 9.4; wet traction: 9.3; cornering stability 8.8; dry traction: 9.2; steering response: 8.9
SP2 Plus:
hydroplaning: 8.0; wet traction: 8.0; cornering stability 8.2; dry traction: 8.5; steering response: 8.2
GY ComforTred:
hydroplaning: 8.6; wet traction: 8.7; cornering stability 8.2; dry traction: 8.9; steering response: 8.1
GY TripleTred:
hydroplaning: 9.3; wet traction: 9.3; cornering stability 9.0; dry traction: 9.4; steering response: 9.0

SP2 outperformed HE in cornering stability, steering response, dry & wet traction (using the braking distance numbers).

You can see the survey results using the "I feel" instrumentation is bogus and almost useless for accurate comparisons.

 

Most of the effective braking in the Prius happens in the electric motor, no? Then the discs up front assist in stopping most of the cars weight at lower speeds (read somewhere front brakes do 70-80% of the stopping in 'other'cars). Then the rears even it all out. Seems the rears are the least used, least critical stopping issue, so lower cost drums make sense for this type/size of car. They would not add alot to the overall stopping of the Prius, just to evenly bring the car to a stop.

A larger faster car is another story...

Cheers,

Curt.