The Hemi: worse gas mileage in cold weather?
Registered User
Joined: Jan 2011
Posts: 3
Likes: 0
From: North Dakota
My 07 1500 always drops in the winter, I have always attributed it warm up times where the truck sits idoling as well as the increased ethonol in the gas. I was expecting a bigger drop when I turned the MDS off, but that didn't effect the millage that badly. However, I was running about 13.3 MPG this summer, (Mostly city 70% or so) I live in North Dakota and am dropping quickly, I'm down to 10.1 MPG or so. If last winter was any indication, I'll be down to near 8... :-/
Veteran
Joined: Jan 2010
Posts: 411
Likes: 2
From: Williston,sc
I think nolimit was referring to star tron I believe hammer or someone on here posted something about it a while back I just got some yesterday to see how well it works for myself I'll post back after a while and let you know
Administrator
Joined: Jul 2007
Posts: 24,686
Likes: 21
From: South Georgia/East Florida
I'm down to one gas station in my area that sells non-ethanol gas and he doesn't take credit cards. At the price of fuel anymore and the size of my tanks, I just don't regularly carry enough cash to fill up my vehicles and it's a PIA to remember to hit the bank or ATM (plus my bank just started charging for ATM withdrawals - even at their branches. Now it's no big deal, I just use the StarTron and I'm getting the same results as when I was buying non-ethanol gas...
Last edited by HammerZ71; Nov 22, 2011 at 11:53 AM.
Record Breaker
Joined: Dec 2008
Posts: 2,032
Likes: 1
From: Elk Rapids, MI
My stock 17's clear the calipers by a very small amount. Without measuring (going by memory), I would be guessing 3/8 of an inch or so. So at best, your 20's may be 1 1/2" further away, but they are probably thicker so most likely even less than that.
Administrator
Joined: Jul 2007
Posts: 24,686
Likes: 21
From: South Georgia/East Florida
Good for ALL 2 and 4 cycle engines...
Grand Champion
Joined: May 2006
Posts: 6,041
Likes: 0
From: Gilbert, Arizona
There are a few factors that come into play here. Each one hurting your fuel economy a little and when added up, the result can be major. Most have already been touched on in this thread.
First of all, by early November we are all getting "winter blend" fuel. The winter mix has a higher Reid Vapor Pressure which results in slightly less energy per volume of gasoline. In other words, you have to burn a little more of it to get the same results as with "summer gas".
Temperatures are decreasing, lower temperature air is more dense and the more dense the air is, the more fuel must be mixed with it to yield the same air/fuel ratio.
A CAI lets in more air volume simply due to the increased surface area of a cone filter vs. a flat filter. More air = more fuel needed, more COLDER air means that much more.
Air pressure in tires decreases as air temperature decreases. Running on lower air pressure results in greater road surface resistance which yields lower fuel economy.
20" wheels are significantly heavier than 17" wheels requiring more energy to move them. Energy overhead is higher in colder weather than warmer due to all of the factors I've listed. If you need a certain amount of energy to move your truck in 80* temps, you will require more energy to move it in 40* temps...
First of all, by early November we are all getting "winter blend" fuel. The winter mix has a higher Reid Vapor Pressure which results in slightly less energy per volume of gasoline. In other words, you have to burn a little more of it to get the same results as with "summer gas".
Temperatures are decreasing, lower temperature air is more dense and the more dense the air is, the more fuel must be mixed with it to yield the same air/fuel ratio.
A CAI lets in more air volume simply due to the increased surface area of a cone filter vs. a flat filter. More air = more fuel needed, more COLDER air means that much more.
Air pressure in tires decreases as air temperature decreases. Running on lower air pressure results in greater road surface resistance which yields lower fuel economy.
20" wheels are significantly heavier than 17" wheels requiring more energy to move them. Energy overhead is higher in colder weather than warmer due to all of the factors I've listed. If you need a certain amount of energy to move your truck in 80* temps, you will require more energy to move it in 40* temps...
