High temps mean high MPG

[Cancunbadlands]

Hey everyone

I often see the claim that hot weather improves fuel economy because the engine warms up faster and warm air reduces aerodynamic drag. Well, I live in the Caribbean where it's easily 40°C (104°F) or hotter every single day, and I'm only getting 20 MPG despite keeping my tires at 38 PSI

High ambient temperature only helps MPG under perfect highway conditions. In extreme tropical heat, the negatives completely wipe out the benefits.

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[Finnster]

If I could live in the Caribbean, I'd give up my Maverick!

 

[babytruk]

Hey everyone

I often see the claim that hot weather improves fuel economy because the engine warms up faster and warm air reduces aerodynamic drag. Well, I live in the Caribbean where it's easily 40°C (104°F) or hotter every single day, and I'm only getting 20 MPG despite keeping my tires at 38 PSI

High ambient temperature only helps MPG under perfect highway conditions. In extreme tropical heat, the negatives completely wipe out the benefits.

Maybe there’s a sweet spot with the temperature. Another Caribbean amphibian here but highs are between 88f and 92f year round (seasons, I miss seasons).
My Atkinson with Hybrid has given me almost 12k of 45.2mpg. Tires at 36psi.

 

[grandpopa'sMPGs]

after a long drive to Chattanooga TN from Cincinnati averaging 65-70MPH with time lost on drive thru food stops

the actual MPGs will be between 46-47 calculated temperatures bounced betwee 80F-87F

 

[inline_five]

Hey everyone

I often see the claim that hot weather improves fuel economy because the engine warms up faster and warm air reduces aerodynamic drag. Well, I live in the Caribbean where it's easily 40°C (104°F) or hotter every single day, and I'm only getting 20 MPG despite keeping my tires at 38 PSI

High ambient temperature only helps MPG under perfect highway conditions. In extreme tropical heat, the negatives completely wipe out the benefits.

You drive an ecoboost, doing short hops. No wonder your mpg is 20. Many of us with hybrids get double that if not more than double in high temps even with A/C on high.

Atkinson cycle engine is far better at high temps.

 

[inline_five]

Maybe there’s a sweet spot with the temperature. Another Caribbean amphibian here but highs are between 88f and 92f year round (seasons, I miss seasons).
My Atkinson with Hybrid has given me almost 12k of 45.2mpg. Tires at 36psi.

The sweet spot is driving a hybrid, they have an ecoboost. 20 mpg doing short drives is not because it's hot out lol.

 

[MavStangVa]

I run 43 PSI front 35 rear.

Why? Mine are 38 all around.

 

[MavStangVa]

And this is Kansas - let me tell you how many hills!
Actually, some steep areas at first, then more gentle rolling.
But generally, 50% SOC or less. I hate that aspect.

I was told these are hills in Kansas

 

[Finnster]

after a long drive to Chattanooga TN from Cincinnati averaging 65-70MPH with time lost on drive thru food stops

the actual MPGs will be between 46-47 calculated temperatures bounced betwee 80F-87F

My22-24 hybrids(all fwd) get amazing mpg's!
I can't touch that with my 2025 awd, 4KTow.

 

[TheRealEman]

I don't follow my hybrid results quite as closely as some of you, but in Maine I do about 38-41 mpg in winter with pretty aggressive snow tires, and that has bounced up nicely to 48-51 this early summer with the factory summer tread Michelins. I do a mix of local and highway. I live in coastal Maine so it's generally flat.

 

[CaliMav68]

40 psi cold all around. Not just better mpg, but more even (better) wear. Better steering response. Which is a safety improvement as well.

If your tires have a max of 45-50, your chances of a blowout caused by a high than recommended pressure do not increase. Low pressure does.

If your tires are wearing on the outsides faster than the center, on "recommended" pressure, it's time to raise that pressure at least 5 psi.

 

[inline_five]

Now, coming home. What a difference 30° makes. Coming back it was about 65° +/-, same set speed. I stopped at a rest area about 30 miles in which is why the mileage is slightly less. Calculated mph 64.8 so actually a little slower, but only because I didn't have the 30 miles of additional 70 mph highway speed averaging out my last ~4 miles of city speed.

HVAC was off the entire time, no heat or a/c usage at all. Fan was off. Wind was light/variable. Tire pressure was the same.

MPG dropped to 34.8, a reduction of almost 18% just because it was cooler (and not even that cool).

 

[babytruk]

40 psi cold all around. Not just better mpg, but more even (better) wear. Better steering response. Which is a safety improvement as well.

If your tires have a max of 45-50, your chances of a blowout caused by a high than recommended pressure do not increase. Low pressure does.

If your tires are wearing on the outsides faster than the center, on "recommended" pressure, it's time to raise that pressure at least 5 psi.

I grew up thinking this was a thing:

 

[grandpopa'sMPGs]

from Chattanooga to Knoxville, just north of.

actual mileage calculated 61/13.5+46.1140250 MPGs

 

[CaliMav68]

I grew up thinking this was a thing:

I remember that. Proper Inflation. No number. Just left for us to figure out.

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