Big test of 5 LRR tires

[Piwoslaw]

With low RR tires becoming mandatory in Europe as of November 2012 (earlier in new cars), a recent issue of the Polish edition of Auto Bild (Auto Świat 34/783, 16.08.2010) published a test of five low rolling resistance tires: Bridgestone Turanza ER300 Ecopia, Goodyear EfficientGrip, Michelin Energy Saver, Nokian V, and Pirelli Cinturato P7. The tested tires were all 205/55R16, and were tested on a Mercedes C200 CGI, loaded with precise instrumentation, on a flat test track with no wind. All showed a reduction in fuel consumption compared to the standard tire (the article doesn't reveal what the standard tire is in this case). Fuel consumption was measured at three different speeds: 80, 100, and 130 km/h (50, 62.5, 81 mph).

FE	l/100km	mpg(US)
Michelin	6.72	35.00
Goodyear	6.74	34.90
Pirelli	6.87	34.24
Nokian	6.91	34.04
Bridgestone	7.08	33.22
standard	7.34	32.05

Fuel consuption was not the only thing tested, the main focus was safety.
First, the maximum aquaplaning speed.

speed	km/h	mph
Nokian	85.8	53.6
Bridgestone	85.2	53.2
standard	85.1	53.2
Pirelli	83.3	52.1
Goodyear	81.8	51.1
Michelin	78.5	49.1

Aquaplaning on a curve:

lateral acceleration	m/s2	ft/s2
Bridgestone	3.53	11.65
Pirelli	3.35	11.06
standard	3.30	10.89
Goodyear	3.28	10.82
Nokian	3.26	10.76
Michelin	3.01	9.93

Driving on dry pavement:

speed	km/h	mph
Bridgestone	100.6	62.9
Michelin	100.6	62.9
standard	99.9	62.4
Pirelli	99.8	62.3
Nokian	99.4	62.1
Goodyear	99.2	62.0

Driving on wet pavement:

speed	km/h	mph
standard	82.3	51.4
Pirelli	81.6	51.0
Bridgestone	79.5	49.7
Nokian	79.4	49.6
Goodyear	77.7	48.6
Michelin	75.9	47.4

(Note: In this test the car was very hard to control with ESP on when fitted with Michelin and Goodyear tires.)

Braking on dry pavement (from 100km/h, 62.5mph):

distance	m	ft
Bridgestone	36.5	120.5
Goodyear	37.0	122.1
standard	37.0	122.1
Michelin	37.3	123.1
Pirelli	37.3	123.1
Nokian	37.9	125.1

Braking on wet pavement (from 100km/h, 62.5mph):

distance	m	ft
Pirelli	57.6	190.1
standard	57.8	190.7
Nokian	59.7	197.0
Bridgestone	59.8	197.3
Goodyear	62.1	204.9
Michelin	64.7	213.5

Driving in a circle (time for one lap, article did not give radius):

time	s
standard	22.59
Bridgestone	22.73
Pirelli	22.86
Nokian	22.96
Goodyear	23.15
Michelin	23.18

Rolling resistance (measured on a special machine):

Goodyear	7.83
Michelin	7.87
Nokian	9.01
Pirelli	9.67
Bridgestone	10.13
standard	11.90

External noise (average of tests @ 70/80/90 km/h; 44/50/56 mph):

noise	dB
Bridgestone	71.5
Pirelli	71.7
Nokian	71.9
standard	72.0
Goodyear	72.7
Michelin	72.7

Summary: The best low RR tire appears to be the Pirelli Cinturato P7, with Bridgestone Turanza ER300 Ecopia second and Nokian V third. Goodyear EfficientGrip and Michelin Energy Saver may have the lowest rolling resistance, but their performance is at the lower boundry of safety.

Note: The article did not give details about the testing procedures, i.e. how many tries were averaged, etc. I pretty much translated the whole article, plus converted all units.

[euromodder]

Originally Posted by Piwoslaw

Driving on dry / wet pavement:

What do they mean by that ?
Just "driving" doesn't say much

Goodyear EfficientGrip and Michelin Energy Saver may have the lowest rolling resistance, but their performance is at the lower boundry of safety.

That's exactly where I'd put the Energy Saver, especially because of its wet weather performance (or rather lack of it).
It's OK in the dry though.
I also use the wider 205 16" version, rather than the stock 195 15" .
Driven acording to ecodriving / hypermiling principles, you shouldn't get into trouble.


I've removed the original Energy 3 B (I think, could have been E3A) from the car because of their lousy performance - the wider Energy Saver is notably better than that.

[NeilBlanchard]

Did they mention what air pressure(s) they used?

[Piwoslaw]

Originally Posted by euromodder

What do they mean by that ?
Just "driving" doesn't say much

Like I said, there aren't too many details about the testing procedure, so I'm guessing this means some kind of zigzag-shaped driving course.

Originally Posted by NeilBlanchard

Did they mention what air pressure(s) they used?

No. At first I assumed that each tire was at the door sticker suggested pressure, but there was a comment that more or less stated that

The higher pressure, which reduces rolling resistance, also reduces comfort. Of the tested tires, Goodyear had the best ride comfort.

This would imply that the LRR's had a higher pressure than the standard tires. This would be weird, as I haven't seen LRR tires that have higher max sidewall pressure than similar non-LRR tires of the same size. I'd like to see a test of the standard tire with higher pressure, then not only would its RR be lower, but it would also allow a high aquaplaning speed and shorter braking distance (see "Inflation pressure does not affect grip": Autospeed article), making it compareable to the LRR's.

[vtec-e]

Originally Posted by Piwoslaw

This would imply that the LRR's had a higher pressure than the standard tires. This would be weird, as I haven't seen LRR tires that have higher max sidewall pressure than similar non-LRR tires of the same size. I'd like to see a test of the standard tire with higher pressure, then not only would its RR be lower, but it would also allow a high aquaplaning speed and shorter braking distance (see "Inflation pressure does not affect grip": Autospeed article), making it compareable to the LRR's.

Ah yes, but from what we've all seen here, sidewall pressure is taboo in the mainstream world. I'd say they run them at a slightly higher pressure but only by a few psi. There is no way they would recommend sidewall pressure and even if the tire had a sidewall max of 60psi they still wouldn't recommend 40 or 50 psi. As i've said, it's a taboo subject!

But yeah, i totally agree with you. Higher pressure would reduce aquaplaning and even out treadwear. But that would reduce the amount of tires we'd have to buy and we can't have that!

ollie

[ausias]

REmember this post:
http://ecomodder.com/forum/showthrea...-db-18989.html

It also contains data from tires from "official" tests.

I would add to your data also:

http://www.goodyear.eu/de_de/images/...ive-report.pdf
TUEV SUD report on:
TÜV SÜD Automotive Tire Benchmark Test -2009205/55 R16 91 V: Wet & Dry Performance -Lifetime -Rolling Resistance/Fuel EconomyReport No. 76236753-2
Bridgestone Turanza ER300, Continental PremiumContact 2, Goodyear EfficientGrip, Michelin Energy SAver, Pirelli P6 Cinturato Ecoimpact.

autobild sports car test
http://www.carworks.gr/online/pdf/hankook_autobild.PDF

http://www.unigum.pl/images/stories/...65_R15_91H.pdf

http://www.bettertyres.org.uk/_uploa...yre%20test.pdf
i have more data on pdf but i can't attach it because of kB limits in this forum, sorry

Official tests and documentation from European Comission lots of info (there is important info hidden in the zips and endless and boring documents ): radius dependance of tire rolling resistance, rolling resistance of large sports tires being better than small "eco" ones, etc. all the test are anonimously so make and model comparision (or brands: van, car eco, car uhp, etc.) couldn't be done but its interesting.
http://ec.europa.eu/energy/efficienc...f_tyres_en.htm

http://ec.europa.eu/energy/efficienc...g_tyres_en.htm
where you could find these working documents and analyses of tires, summary from independent test with assessments on specific tires (with make and model), etc:
http://ec.europa.eu/energy/efficienc..._documents.zip

[Frankencar]

This is great information! thanks! I plan to run a set of the Pirelli P7 Centurato tires on my GTI - see if I can get the average up to 66 mpg.

[CapriRacer]

I find it really interesting that they document that wet traction is worse for the LRR tires.

[euromodder]

Originally Posted by CapriRacer

I find it really interesting that they document that wet traction is worse for the LRR tires.

Why ?
It's almost a universal feature that LRR tyres perform less well in wet conditions.

[jamesqf]

Interesting, but I'm quite puzzled by one comment:

(Note: In this test the car was very hard to control with ESP on when fitted with Michelin and Goodyear tires.)

I've never found ESP to be a very good way of controlling a car, though it would be very useful for avoiding some of the other drivers on the roads, who do seem to be driving by ESP :-)