Fuel Economy Test #6: Mmm... DONUTS!

Do you think 'donut tires' would increase or decrease a car's fuel economy?

Category:

Autos & Vehicles

Tags:

• donut
• compact
• spare
• tires
• geo
• metro
• regina
• saskatchewan
• canada
• ring
• road
• freeway
• fuel
• economy
• gassavers.org
• landongendur

[05front]

Those donuts also way a lot less

[landongendur]

@05front - they do, but to keep the weight consistent between runs I kept the large tires in the back hatch.

[05front]

@landongendur well you also where not doing 50 or 55 mph. The smaller tires were tricking the speedo.

[landongendur]

@05front - the front tires are what measure the speed (I know this because the speedometer would go up when I spun the wheels in winter). Thus putting on the tires on the rear didn't trick the speedometer.

[armand1280]

That car gets twice the gas mileage of the american spec prius, and without the choking clouds of "smug".

[landongendur]

I bet a Prius would do well too at 50-mph

[05front]

@landongendur oh ok. yea i kinda missed that part during the install lol

[ITBOILSMYBLOOD]

It's not too hard to realize the difference in the mileage. It's the narrower contact patch of the donut spares. The mileage would probably increase to 65 to 68 with donut spares in the front as well. Wider tires will decrease mileage, but will increase stopping power and vehicle handling abilities.

[Jimmetalrules5546]

I'm not sure but i think that could be because fuel is of much higher quality in Europe apparently.

[voltairefrench]

i watched test 5 and seen the 1.4 increase with acetone.. several factors.. you said you had 5 gallons in the tank and added 2.5 or so of acetone.. your controlled test was not too controlled .. most of what i read is that your to add 2 oz per 10 gallons and when you added it i dont think you mixed it properly on most additive you add your to add the stuff first then add gas properly mixing it in your tank... maybe that is one thing you can do on your next test..

[armand1280]

You're probably right. But it's strange how mid to late 90's cars get better gas mileage than newer ones. That, and the European spec prius gets twice the mpg as the American spec.