spacesaver steel wheels

[CapriRacer]

Originally Posted by justjohn

Sorry for the aside, but not sure I understood the explanation for why wider tires are more efficient.

Anyone care to explain?

Barry's Tire Tech

[justjohn]

Hahah. I read it. I just don't get the part about load capacity going up by a greater percentage than tread and how that translates to lower RR.

[Christ]

Alot of people don't like the idea, but trailer wheels have the same bolt pattern as many cars, and are usually pretty thin/light. Standard car tires will fit them. They may out may not clear your brakes.

[Joenavy85]

Originally Posted by justjohn

Hahah. I read it. I just don't get the part about load capacity going up by a greater percentage than tread and how that translates to lower RR.

you transfer the power to the ground via the tires, that power/energy will deform the rubber (make the raised parts of the tread flex), the more flex the more resistance, when you spread out the contact patch you reduce the flex on a given area. the downside is that when you use wider tires you COULD increase your frontal area, depending on the ride height of your car and how much tire is exposed

[Christ]

Shouldn't the rubber act like a spring, and a large percent of that energy used to flex the rubber be returned by the rubber returning to it's original position?

[Joenavy85]

but the energy of the rubber returning to it's original position isn't doing anything to help the motion of the car

[Christ]

I've had that thought about valve springs, as well... But I've been "corrected".. Not that I believe it.

[justjohn]

Originally Posted by Joenavy85

you transfer the power to the ground via the tires, that power/energy will deform the rubber (make the raised parts of the tread flex), the more flex the more resistance, when you spread out the contact patch you reduce the flex on a given area. the downside is that when you use wider tires you COULD increase your frontal area, depending on the ride height of your car and how much tire is exposed

Okay, but wouldn't that be only an increase when you're on the gas and wouldn't more contact with the ground still mean higher resistance while coasting?

It seems weird that it would still come out as a significant decrease to me.

[zonker]

Originally Posted by SuzukiSteve

I been running this set up for 6months/15,000 miles. Nissan Altima spare rims fit my suzuki siwft/geo metro lug pattern.
My boss Glenn did a write up of it over on GMF. Pictures Included!
15" Wheels and VW Tires

These wheels have your same bolt patterns and look killer, as well as are even lighter (the seller in the ad is off his gourd tho thinking it's worth 99 bux). U can get these are the pick and pull as well... just look in the back hatch of any 4 lug 86-88 mazda rx-7.

86-88 Mazda RX7 Spare Tire Alloy Wheel 15x4 4-1/2" OEM | eBay

[rmay635703]

Originally Posted by justjohn

It seems weird that it would still come out as a significant decrease to me.

Thats because it may not be a significant decrease, many cars are not running anywhere near the weight rating of the car on each tire. If your loaded to 20% of the max load the tire can handle (which several of my cars are or better) it may not decrease anything and in fact be overridden by the increase in frontal area. (wind resistance)

In the real world you may find that its basically a wash.