Tire Upgrade

[hyo silver]

Originally Posted by Wa1hog

...I have noticed that my speedometer is usally 1 to 2 MPH faster than what my GPS says Im going.

Originally Posted by F8L

...The stock Prius tire size in the U.S. is 185/65/15. Overall you want to try and maintain the stock 24.4" diameter.

This may have been discussed sometime in the last few hundred posts, but I'm not about to reread the whole thread to find out. My apologies if you've heard this before.
Knowing that the speedo reads a bit fast with the stock tires, wouldn't a tire that's slightly smaller improve the speedo's accuracy? I'm thinking the TT's revolutions per mile of 862 as a replacement for the Integrity's rpm of 855 is just about perfect.

[nyprius]

Originally Posted by mtagg49

Thanks for the great research - have you had any experience with the 195/60 TT in snow?

Mike from Chappaqua

The TT's are great in the snow and rain, as well as on dry pavement. They're an excellent all around tire. My only complaint is that they've gotten noisy now that I have over 40,000 miles on them. The tread will probably last to 60,000 or 65,000 miles. Not 80,000.

When it's time for new tires, I'll try something new. I want a tire that has excellent handling like the TT, but is quieter. I'd also rather get a non-directional tire next time. This way I can move the tires to the other side of the car if I have a pulling problem that isn't fixed by alignment. I have a slight pull now and have to live with it. I'm not sure if the pull is caused by the tires since I can't switch them over to the other side to test, unless I take them off the rims, which I'm not going to do.

[jdenenberg]

Originally Posted by hyo silver

Knowing that the speedo reads a bit fast with the stock tires, wouldn't a tire that's slightly smaller improve the speedo's accuracy?

No, smaller tires will make the speedo read higher. You need a tire with fewer revs/mile to adjust the speedo lower (note that this will appear to lower your MPG by the same %, but the change is not real).

JeffD

[dwreed3rd]

Originally Posted by jdenenberg

No, smaller tires will make the speedo read higher. You need a tire with fewer revs/mile to adjust the speedo lower (note that this will appear to lower your MPG by the same %, but the change is not real).

JeffD

jdenenburg: I don't know if Hyo Silver has an SGII, but if so, I believe there's a mileage adjustment. In fact, I know there's one. I went crazy trying to set it for the Avalon. That's when I realized the Georgia's mile markers are all screwed up with all the new construction on GA 400. Anyway just a thought.

[kcribk]

Has anyone researched (or had experience with) the Yokohama Avid T4 or the Yokohama YK520?