Practicality of tire upgrade
 

I have researched and know that larger skinny tires tend to improve highway fuel economy; however, my curiosity is how practical this is tire upgrade on an automatic transmission vehicle. I currently have the 215/60r16 installed and am looking at either the 225/60r16 or the 205/65r16. The car is a 2000 Ford Taurus that all other aero mods attempted so far have yielded no result. The only things that worked were properly inflated tires and a modified p&g style while leaving the car in drive. Sorry, just wanted to give a quick history to apply to this tire question. I am concerned the increased tire size will yield no result, or a negative one.

Thanks

I entered into this accidentally with my Dodge Caravan.
It came with 225/65R16 tires but my local Michelin dealers did not have winters in this size.
I opted for 215/70R16. Same rolling radius, but narrower.

Kind of an apples and oranges comparison, all-season Yokohama to winter Michelin,
but the narrower tire feels less secure, less stable on the road, and yet has very
slightly less rolling resistance (tested before and after change on a nearby hill).

Steve

That is a concern I have, as I tend to corner at rather high speeds. I would actually be tempted to go a little wider, and taller. I don't see the 225/60's changing things too much. The car seems to average 25 mpg on 87 no matter what I do. The only huge difference has been with premo gas, which doesn't make sense. And is also irrelevant to the current discussion.

Sentraguy, I know where you're coming from on this.
Experimenting with tyre size can get very expensive if you find you've jumped the wrong way and want to change back.

I recently changed tyre size with great success, by buying a cheap set of secondhand tyres on steel wheels. I went from 195/50/15 to 195/60/15.
It took me a while watching ebay, but I found a set for $50 that I've run for the last 6350 km.
This only worked for me because the Mazda gearbox ratios are too short for my particular driving conditions (mostly highway). You would know better than I how happy your Taurus is at speed.

I thought the taller tyre might adversely effect handling, but that hasn't been the case for my Mazda, so much so, that I'm keeping an eye open for a cheap set of 195/65/15's to try next.

Short answer: Tire size is NOT important, but differences between tires (meaning make and model) can be HUGE!! Careful selection could pay dividends!

Long answer: Barry's Tire Tech

another little secret ,well I guess not really, is that new tires get worse mpg than older smoother tires, rock hard 5 year old almost bald tires get great mpg , but of course arent safe.

Also a tire that is "aged" will also be slightly better. When you buy "fresh" straight from the factory the tire is not as cured as a tire that has sat on a shelf for a little while. I felt the difference between a brand new tire and last years stock and the older tire was firmer in the tread and and sidewall. It is also possible the the batch of rubber could be different but talking to my tire guy he said it is very common for an older tire to be firmer.

Capriracer - I look forward to your reply on this information (True or False)

I understand that the ribber compounds all have oil and carbon in them and the rubber eventually evaporates and leaves behind the harder materials, also much less traction on even almost new looking old tires, so i'm sticking with new, buy a lot of gas for what an accident costs,

I agree, I don't think you should let your tires sit around for years. I just question weather allowing the tire to cure a little longer may be beneficial? Paint, lacquer, adhesive are all dry to the touch in hours but have a much longer cure time. Latex paint will ball up if you try sanding it for repaint within a couple months of application. Most autobody shops advise waiting a couple months before waxing a new paint job. I have tested silicone adhesive at work and silicone that is allowed to cure for a year is almost impossible to remove but even silicone allowed to cure for a month or two can be removed very easy.

I appreciate all the input. I especially loved the long answer, thanks. I am thinking about trying the 225/60's as they are not that much bigger. I do hot rod the car a bit at times, and the wider tire should definitely help cornering. And the issue with the back tires is they are going flat due to dry rotting. My dad worked for Goodyear for almost 30 years and informed me that the cheaper tires are more prone to dry rot than the better made tires. It would be interesting to see how big a difference there is between the batches.:rolleyes: