I Don't Think My Yaris Has DFCO

[BailOut]

I see 45mph speeds listed. If thats the case, its no wonder you get in the 40+ range per gallon.

As you mentioned that is the average speed, taking into account city and highway driving (30-35 MPH in the city, 55-60 MPH highway). The reality of my daily commute is a twisting, winding, 2 lane, 30-50 MPH climb over a 4,500ft mountain (8,900ft summit), dropping 2,500ft on the back side, then the opposite on the way home. That is very far from optimal mileage conditions, especially in the colder months.

If you want to get better MPG on the highway the #1 thing you can do to help yourself is to slow down. Every MPH you drive over 55 takes away 1% of your fuel efficiency, and every MPH above 65 takes away as much as 5% due to the physics of aerodynamics. A common example used is that it takes an average of 20% more fuel to drive 70 than it does to drive 55. Get in the right-hand lane and stick to 55 MPH and watch your MPG shoot up.

Pumping up your tires to at least the max sidewall rating not only improves handling on wet and dry pavement but also increases MPG by decreasing rolling resistance, and increases the life of your tires by producing a much more even tread wear pattern. As an example I run my RE92's at 60 PSI for most of the year, dropping them to 44 PSI (which is the max sidewall) in snowy conditions.

Btw, the site linked in my sig, CleanMPG.com, isn't mine. I'm just a member and contributor. You can read much more about increasing your MPG there, and start logging your own fuel usage if you like.

[CASTREX]

Originally Posted by BailOut

every MPH above 65 takes away as much as 5% due to the physics of aerodynamics.

Pumping up your tires to at least the max sidewall rating not only improves handling on wet and dry pavement but also increases MPG by decreasing rolling resistance, and increases the life of your tires by producing a much more even tread wear pattern. As an example I run my RE92's at 60 PSI for most of the year, dropping them to 44 PSI (which is the max sidewall) in snowy conditions.

Last night I was doing 110 MPH, that means... 225% more fuel !!!! well it was fun tough...

60 PSI ???? that's like twice the recommended pressure for the car!!
So it's Toyota recommending low tire pressures for us to get bad MPG ??

[BailOut]

Originally Posted by CASTREX

So it's Toyota recommending low tire pressures for us to get bad MPG ??

Toyota recommends a tire pressure based solely on ride comfort/smoothness rather than anything to do with mileage or handling.

The recommended 32 PSI is one half of the reason the Yaris feels like it's rolling laterally sometimes, especially in corners or high winds (the other half is the suspension). This is also one of the main things that leads to all the complaints of crappy and sluggish handling.

With the tires at 44-60 PSI there is a noticeably rougher ride as evidenced by slightly feeling a highway concrete joint in your seat when you used to just feel it on the control surfaces but that is a very small price to pay to get an MPG boost and much better handling.

For example, on the downhill side of my commute home there are 2 tighter-than-usual right-hand turns. They each have the warning signs for 30 MPH and back in my 32 PSI days I used to take them between 25 and 35 and could sometimes feel a little slippage. Now at 60 PSI I blow through there in a 5th gear DFCO at 45 MPH without so much as a tire squeal or wobble.

[CASTREX]

Originally Posted by BailOut

Toyota recommends a tire pressure based solely on ride comfort/smoothness rather than anything to do with mileage or handling.

The recommended 32 PSI is one half of the reason the Yaris feels like it's rolling laterally sometimes, especially in corners or high winds (the other half is the suspension). This is also one of the main things that leads to all the complaints of crappy and sluggish handling.

With the tires at 44-60 PSI there is a noticeably rougher ride as evidenced by slightly feeling a highway concrete joint in your seat when you used to just feel it on the control surfaces but that is a very small price to pay to get an MPG boost and much better handling.

For example, on the downhill side of my commute home there are 2 tighter-than-usual right-hand turns. They each have the warning signs for 30 MPH and back in my 32 PSI days I used to take them between 25 and 35 and could sometimes feel a little slippage. Now at 60 PSI I blow through there in a 5th gear DFCO at 45 MPH without so much as a tire squeal or wobble.

None of the following links agree with your statement.

I just think that running on 60psi tires is not very safe... even more if you are driving up and down a hill every day.

http://www.sportcompactcarweb.com/te...ressure_guide/

http://www.tirerack.com/tires/tirete....jsp?techid=72

http://www.nhtsa.dot.gov/cars/rules/.../brochure.html

[Chris07LB]

Thanks for the info, Ill be sure to look into the site a little more.

Side not, you ever try doing 55mph even in the slow lane in NEW JERSEY??? Aint gonna happen!!

Originally Posted by BailOut

As you mentioned that is the average speed, taking into account city and highway driving (30-35 MPH in the city, 55-60 MPH highway). The reality of my daily commute is a twisting, winding, 2 lane, 30-50 MPH climb over a 4,500ft mountain (8,900ft summit), dropping 2,500ft on the back side, then the opposite on the way home. That is very far from optimal mileage conditions, especially in the colder months.

If you want to get better MPG on the highway the #1 thing you can do to help yourself is to slow down. Every MPH you drive over 55 takes away 1% of your fuel efficiency, and every MPH above 65 takes away as much as 5% due to the physics of aerodynamics. A common example used is that it takes an average of 20% more fuel to drive 70 than it does to drive 55. Get in the right-hand lane and stick to 55 MPH and watch your MPG shoot up.

Pumping up your tires to at least the max sidewall rating not only improves handling on wet and dry pavement but also increases MPG by decreasing rolling resistance, and increases the life of your tires by producing a much more even tread wear pattern. As an example I run my RE92's at 60 PSI for most of the year, dropping them to 44 PSI (which is the max sidewall) in snowy conditions.

Btw, the site linked in my sig, CleanMPG.com, isn't mine. I'm just a member and contributor. You can read much more about increasing your MPG there, and start logging your own fuel usage if you like.

[d2dailly]

Originally Posted by Chris07LB

Thanks for the info, Ill be sure to look into the site a little more.

Side not, you ever try doing 55mph even in the slow lane in NEW JERSEY??? Aint gonna happen!!

i feel ya. i am always doing about 80 in the fast lane but when i get people up my ass i hit 100 or 110 lol NJ has very aggressive drivers. guess thats why insurance is so high here

[Kaotic Lazagna]

Originally Posted by d2dailly

i feel ya. i am always doing about 80 in the fast lane but when i get people up my ass i hit 100 or 110 lol NJ has very aggressive drivers. guess thats why insurance is so high here

wow, the fastest i've ever driven in my Yaris was 85 mph. LA also has some aggressive drivers.