Tire Suggestions...

[2000mc]

goodyear fuelmax P185/65R14 and you should be able to get a $40rebate

[KrautBurner]

Originally Posted by 2000mc

goodyear fuelmax P185/65R14 and you should be able to get a $40rebate

looks like those go for $100 each
Goodyear Assurance Fuel Max Tire P185/65R14 - Walmart.com

that makes them about $550 for the set


the General's I ordered (should have them installed monday) were $65 each
that's about $350 installed (after Labor and Tax)
and they have a $100 rebate

[Big Dave]

As rolling resistance data is closely guarded, one default you can assume is that the OEM rubber is the lowest RR you are likely to find. This is data the OEM has to submit to the EPA to get an MPG rating and as MPG ratings are often sales points, the OEM has a reason to use the lowest RR tires possible.

Keep the skinny tires.

[CapriRacer]

Big Dave,

I hope you understand that I am trying to correct a misconception and I'm not picking on you or your post. Just merely trying to get the facts straight.

Originally Posted by Big Dave

As rolling resistance data is closely guarded.........

It's more like there are several ways to express RR and there is no agreement which test to use. In other words, different tests yield different results, so unless the tests are the same, you can't be certain of any particular value that is quoted.

And rather than get into a pissing contest with their competitors, they've chosen to be purposely vague.

Originally Posted by Big Dave

....., one default you can assume is that the OEM rubber is the lowest RR you are likely to find.......

This is very likely true. I don't know of any tires that have truly low RR values that aren't OEM.

Originally Posted by Big Dave

........... This is data the OEM has to submit to the EPA to get an MPG rating..........

Actually, the RR values aren't submitted. The overall vehicle test results are and the tire's RR value as well as the engine's efficiency, transmission losses, etc. all contribute to the value obtained. The tire's RR is just little bit of the overall picture, but the government doesn't know what the RR values are (unless they test them themselves.)

Originally Posted by Big Dave

...... and as MPG ratings are often sales points, the OEM has a reason to use the lowest RR tires possible........

Well ...... sort of. RR is part of the technology triangle where traction and treadwear form the other legs. Any improvement in one area is done at the expense of another area. It's a delicate balance that vehicle manufacturers sometimes get wrong - one of the reasons why OE tires are generally considered "poor quality". But OE tires aren't always the lowest RR values possible - sometimes the vehicle manufacturer will emphasize traction in order to impress journalists.

Originally Posted by Big Dave

......Keep the skinny tires.

Skinny isn't so much the over-riding factor in RR. There are other things that have a much larger effect.

[Vekke]

Also remember that when talking only rolling resistance in same tire size effect to fuel consumption is only max 7-8% better fuel consumption between best and worst. Now you can easily make calculations is it worth to buy brand tires or not. Based on Finnish tire magasize tests usually it is as brand tires tend to last up to twice the miles longer.

I would not fully trush the wear ratings or what you think Capriracer is there some legislation that manufacturers cannot lie on that rating?

If you open the door to changing size totally different the bigger diameter (longer distance travelled) and aerodynamics (narrow) effect more than the LRR compound.

I would go for 175/80R14 if you can find a good set (if your state laws allow them). In finland you can find over 35 manufactuers for that size so there must be some importers to US also... At least in Finland you can buy used set easily 50-100$ so you can test their effect. If they dont work sell them and buy different size.

[CapriRacer]

Originally Posted by Vekke

........I would not fully trust the wear ratings or what you think Capriracer is there some legislation that manufacturers cannot lie on that rating?........

Well, sort of.

The tire manufacturers can not OVER state the wear rating - and they have to do the comparison to a standard tire (so you can compare between brands) - BUT - not only can the tire manufacturers UNDER state the wear rating, they can run the test a number of times, selecting the best result (if they want). Or they can run the test such that the comparison to the standard tire is through multiple tests, taking advantage of the error in each test.

So while you can compare treadwear ratings, you have to take them with a grain of salt. There is probably little difference between tires rated within 10% of each other (say, 400 vs 440), but there will be a difference between tires rated more than that (say, 300 vs 400) - keeping in mind that understating the wear rating is possible.

Originally Posted by Vekke

........If you open the door to changing size totally different the bigger diameter (longer distance travelled) and aerodynamics (narrow) effect more than the LRR compound.....

I thoroughly disagree. The RR of tires in the same size can vary up to 60%. Small tire size changes are on the order of a couple percent. Tire aerodynamics is even smaller. Gearing changes due to tire size might have a larger affect, and probably worth the trouble, particularly considering there are 2 things going in the positive direction (gearing and RR)

[Vekke]

Rolling resistance can be bigger % change but the effect to fuel consumption is max 7-8% at least what I have seen in local magazines (been following the tests over 4 years perioid summer and winter tires) and they have usually one or two reference tires of chinese marks (non brand) just to see the level of their performance.

This years test had 16 tires and biggest difference was 6% to fuel consumption. and the suprice performer was Landsail LS288 which outrun few of the brand tires in some tests. That tire set reference price was 350€ 8.6 points of 10 vs winner Continental Contipremium Contact 5 550€ per set 9.5 of 10. tested size was 205/55R16