Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Tires: Sidewall stiffness and fuel economy

AeroModder · 04-02-2010, 05:50 PM

I'm looking at tires to get that'll lower my rolling resistance and give me better gas mileage, but I'm also looking for something that isn't squishy in turns. I've been looking for a tire with stiffer sidewalls than what I have now, and I just started comparing max inflation pressure. I was looking at the Pirelli P4s (Pirelli P4 Four Seasons), but I noticed the inflation pressure is pretty low. Now I found the Yokohama Avid Touring (Yokohama AVID TOURING-S) which has a slightly lower treadwear rating, but can go up to 51 PSI. To get the stiffer sidewalls, I'd need to get 195 wide tires instead of the stock 185, and I know the wider tire takes a hit in drag, but the 185s are all softer-walled.

Has anyone noticed if the sidewall stiffness has any effect on fuel economy?

EDIT: After some reading, I'm finding completely contradictory reports. Some say a stiffer sidewall rolls easier, reducing RR, but other say that a softer sidewall absorbs bumps better, reducing RR. Which is it? Soft or stiff?!?

04-02-2010, 05:50 PM	#1 (permalink)
AeroModder Master EcoModder Join Date: Jan 2010 Location: Oregon Posts: 471 Tank - '96 Ford Aspire 4 door Team Ford 90 day: 46.75 mpg (US) Thanks: 15 Thanked 65 Times in 48 Posts	Tires: Sidewall stiffness and fuel economy I'm looking at tires to get that'll lower my rolling resistance and give me better gas mileage, but I'm also looking for something that isn't squishy in turns. I've been looking for a tire with stiffer sidewalls than what I have now, and I just started comparing max inflation pressure. I was looking at the Pirelli P4s (Pirelli P4 Four Seasons), but I noticed the inflation pressure is pretty low. Now I found the Yokohama Avid Touring (Yokohama AVID TOURING-S) which has a slightly lower treadwear rating, but can go up to 51 PSI. To get the stiffer sidewalls, I'd need to get 195 wide tires instead of the stock 185, and I know the wider tire takes a hit in drag, but the 185s are all softer-walled. Has anyone noticed if the sidewall stiffness has any effect on fuel economy? EDIT: After some reading, I'm finding completely contradictory reports. Some say a stiffer sidewall rolls easier, reducing RR, but other say that a softer sidewall absorbs bumps better, reducing RR. Which is it? Soft or stiff?!? __________________ In Reason we Trust Last edited by AeroModder; 04-02-2010 at 11:01 PM..