Speed rating versus grip => higher isn't necessarily better

Thursday, May 27, 2010 by Cy Chowattukunnel
Does a higher speed rating mean faster times and more grip? Will a Y-Speed Rated (186 MPH) tire be faster and grippier then a W-Speed Rated (168 MPH) tire?

Not necessarily. Grip and performance depend on the tire's compound, bead construction and other attributes. 

A higher speed rating means the tire will deflect less at higher speeds due to the tire's circumferential reinforcement, but the tire's compound may not be grippy.

Consider the tire results of Car and Driver's comparison test from last summer.

In the dry autocross test, the fastest tire was the W-Speed Rated Kumho Ecsta XS.



Comments on Speed rating versus grip => higher isn't necessarily better

Friday, December 7, 2012 by Bob Brasill:
do you have a tire that is rated for 200 mph?
Friday, December 7, 2012 by cy:
We don't have a tire Speed Rated above 200 MPH but we have a few tires that are Speed Rated 186+ plus. This means the tire manufacturer has rated the tire as capable of doing some unspecified rating above 186 MPH. You can identify these tires by the Y at the end of their Service Description and the fact that the Service Description is in parentheses. For example, 285/35-19 Max Performance Summer Goodyear Eagle F1 Asymmetric 2 has a (103Y) Service Description, see:

http://www.tirerack.com/tires/tires.jsp?tireMake=Goodyear&tireModel=Eagle+F1+Asymmetric+2&partnum=835YR9F1A2XLN0&vehicleSearch=false&fromCompare1=yes&affiliate=FL7

Continental makes the ContiSportContact Vmax rated for 225 MPH but this tire is no longer exported to North America, see more on these here:

http://www.conti-online.com/generator/www/de/en/continental/automobile/themes/car-tires/summer-tires/contisportcontact-vmax/contisportcontact-vmax.html

Thanks.

Cy

Leave a comment





Captcha