Tire pressure and fuel economy RESULTS - Page 6 - Fuel Economy, Hypermiling, EcoModding News and Forum

trikkonceptz · 10-30-2008, 04:24 PM

Maybe we should start our own database of information regarding the subject. We have enough here that have used more than one matched set of tires and we all track our psi religiously.

For example;

1 SET of tires (Goodyear Eagles)
-No hypermiling techniques
-Factory PSI maintained @ 35psi
-Tires wore bald and even @ 12000 miles
-Rotated every 3000 miles (Oil Change Interval)

2nd Set (Goodyear Eagles)
-Hypermiling from day 1
-PSI @ 55, max side wall 44psi, checked weekly
-Currently have 20000 miles on them, 60% tread left
-Even wear on all tires
-Rotated every 10000 miles
-Experiencing better cornering, better wet weather traction, rougher ride

If we keep this type of log somewhere, it may be more difficult to dispute an hopefully begin to open peoples eyes up.

CapriRacer · 10-30-2008, 04:52 PM

Quote:

Originally Posted by Tony Raine

all i have to add are my own experiences.

2001 ford explorer sport, 2 sets of 31x10.5 generic mud tires

1st set:
-don't remember how many miles i got out of them, but it was quite a bit for mud tires. maybe 35,000 or so
-tire pressure kept at ford specs religiously (35 front, 30 rear)
-tires rotated every other oil change (every 10,000 miles)
-the tires in the front cupped pretty badly, thought it was an alignment problem.
-lots of body roll and bounce getting on the highway.

2nd set:
-10 to 15,000 miles so far, very little wear
-about to do first rotation (im due to change my oil)
-45 psi all 4 corners for most of those miles
-tire cupping is non-existent (and i never got an alignment)
-handling is very noticeably improved (its still a lifted suv, but its much better than even bone stock)

A couple of thoughts:

First, Tire Guides - which summarizes the vehicle placards, says that 2001 Ford Explorer Sports all had P metric tires originally and all used 30 psi. I'm going to assume that this vehicle came with the P235/75R15 tires, since the tire sizes indicated was 31X10.50.

Assuming that what I looked up is correct, to get the same load carrying capacity as the original tires, a 31X10.50R15LT would need to be inflated to ...... drumroll, please ......... 45 psi.

That means the 1st set were UNDERINFLATED - so there is no surprise that there were tire wear problems!!

It also means the second set were PROPERLY inflated - per the vehicle placard if you count the change in tire size.

BlackDeuceCoupe · 10-30-2008, 05:03 PM

Quote:

Originally Posted by trikkonceptz

Maybe we should start our own database of information regarding the subject.

For example:

1 SET of tires (Goodyear Eagles)
-Factory PSI maintained @ 35psi
-Tires wore bald and even @ 12000 miles

2nd Set (Goodyear Eagles)
-PSI @ 55, max side wall 44psi, checked weekly
-Currently have 20000 miles on them, 60% tread left

Excellent idea!

I'm running Pirelli Cinturato P3000 tires - which are premium quality passenger tires - 85,000 mile warranty, yada, yada, yada.

A common complaint with these tires @ door sticker pressure (or less) is oddball wear patterns, run-out, and so forth, and so on...

I alternately drive my car like a madman or a granny. I'm either trying to hit 150 mph or get 150 mpg, depending on my mood. And, I'm here to tell you that these tires are performing and wearing GREAT @ 50 psi.

These tires are going to weather-crack and rot off my car before the tread is gone - guaranteed - and I attribute a lot of this to over-inflating them!

MazdaMatt · 10-30-2008, 05:12 PM

subjective comments regarding "feel" and wear for a large group of people in a large variety of cars and a large variety of tires and tire sizes is a pretty random data set from which you can gain nothing. Remember, 80% of drivers think that they are better than 80% of drivers. that is to say that people don't know sheet about how their cars are "handling" even if they think they do. Having everyone here run a series of tests on their cars with exact parameters and data collection devices would tell you something. Otherwise its like saying "i put a cyclone in my air intake and it FEELS like i'm getting better milage!"

Anybody read that article i posted? It is pretty much indicative of what everyone who LEARNS how to maximize grip agrees on. Go to a performance school or read up on a performace guide on the net somewhere.