Gasoline. Summer versus Winter Blend Differences

[Steve G.]

  It turns out that there are big differences between summer and winter blends. I looked into this because soon I'm about to head to my closest E-0% fuel supplier with jerry cans to have E-0% ready for my old carbureted bikes. But I'm going to wait until all Northwest refineries have done their swap over and delivered their summer blends to their gas stations.
 
 Essentially, winter fuel blends have a higher "Reid vapor pressure", RVP, meaning they evaporate more easily in winter to allow easier cold starting. Refineries use butane to achieve this, but butane has lower BTU.
However, summer blends have higher BTU, so they offer 3-10% better fuel economy.  Summer/winter blends differ based on geographic locations and historical temperatures, generally Pacific Northwest delivery summer blend gasolines have 2.5% more energy [BTU] capability than winter blends.
  Current 2024 summer blend delivery for purchase in the PNW no later than April 15.

[Runningdog]

Well, that may explain why my car indicates high 9s l/100km in the summer, but struggles to stay below 11 l/100km in the winter.

[hardrockminer]

There are lots of things affecting gas mileage.  If you never check tire pressure it will be lower in the winter.  This means lower gas mileage.  Air is thicker....means more air resistance.  Ice and snow builds up on the vehicle...more air resistance. 

I've given up trying to find E0 gas.  I'll just do a carb and engine rebuild more often.  Maybe once every 10 years instead of once every 20.

[Steve G.]

  There is no  E0% gasoline easily available in Canada as of July 2023 thanks to the current federal government. Anyone who voted  for this current  ‘situation’  is responsible.  I live 12 miles from the USA where it is still available.

  I check tire pressure every 7 days. I run 42 psi.

  Air density is thicker in the winter. This causes extra wind resistance, but also higher air density  increases engine power. Drive from sea level at Kona on the big island Hawaii to Mona Kea  at  13,800 ft with invisible density, the rental car barely makes it.

  Ice and snow causes wind resistance. There are many instances in winter where there is no snow or ice on the vehicle, but fuel economy is still less.

[hardrockminer]

In general I would say 42 psi is a bit high, but it depends on the tires to some degree.  I normally run around 32 to 35 on my truck.

Most folks idle their vehicles in the winter after starting, but don't do this in the summer.  This hits their gas mileage.  A good wheel alignment will also help gas mileage, but this applies year round.

[Steve G.]

  I’ve run 40-42psi in my tires since I was 16. My last set of tires on my truck lasted 175,000 kms.

[Galactica]

  I’ve run 40-42psi in my tires since I was 16. My last set of tires on my truck lasted 175,000 kms.

On my truck I run the tires at the spec pressure.  Can’t remember what it is off hand.  My tires are wearing like iron.  They are ok I guess for grip in the dry, but absolutely SH*T when there’s even a tiny bit of moisture on the road.  Slip and slide like on snot.  I can drift corners at will.  Just pray I don’t have to make any emergency manoeuvres.

I’d gladly give up some wear for better grip.  And that applies to both my summer and winter tires.  In the fall I intend to get some better snowflake tires that I’ll run all year round.  I only put on 5-10K km per year.   

Running higher pressures may give you a tiny bit of extra fuel economy but it would be very incremental and would (to my mind) reduce overall grip.  I’d rather give up a tiny bit of gasoline for better overall performance. 

[Steve G.]

  Regardless of what tire ‘type’ you use , you gain .2%  increase in MPG for every 1 psi tire pressure. Different tire types have different levels of rolling resistance, but that ratio remains the same regardless of tire type. One may mock .2%, I do not considering the city of Vancouver has the highest gasoline prices in North America, specifically because of taxes. Yes, Inuvik probably has higher gas prices, I’m saying a place where there isn’t a 2000 mile delivery by truck for fuel.

 My 0% ethanol fuel source will confirm summer fuel delivery on Monday. Their refinery is in Western Minnesota using Alberta oil.

[Steve G.]

  March 1st, it's confirmed that ethanol free summer blend gasoline is now available at all stations in WA State Whatcom County.

[EPL]

Ethanol free is available at my local Home Depot  store (Victoria) - in the lawnmower/garden tool section, comes in a 3 litre tin, for a mere $28 plus tax!  Says that it is 92 Octane and has 'preservative' in it.

[Steve G.]

Ethanol free is available at my local Home Depot  store (Victoria) - in the lawnmower/garden tool section, comes in a 3 litre tin, for a mere $28 plus tax!  Says that it is 92 Octane and has 'preservative' in it.

   Aspen fuel.