Higher MPGs

Published in the August 2012 issue of “Die Porsche Kassette”

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With the price of gasoline at $3.50 and higher I get a lot of: “How can I get better gas mileage from my Porsche?”

I generally tell them: “I can sell you a Kit to increase horsepower which will make your car more efficient giving you better mileage, or just  follow some of my gas-saving tips”:

1.-  TUNE-UP

Keeping the factory-recommended maintenance service schedules is one of the best ways to gain fuel economy.  These scheduled maintenance services make sure that the spark plugs are in optimum condition, that the brakes aren’t dragging, that the engine breathes properly with a clean filter, that your oxygen sensors are reading the exhaust correctly and that your ECU is adjusting the fuel/air mix in the most efficient way, among other issues.

2.-  TIRES

Having your tires properly inflated can save you a couple of MPGs.  Check your owner’s manual or the tire-inflation sticker on the door jamb for your car’s recommended tire pressures.  Note that with our Porsches, we generally have different front-to-back tire pressures and remember that tires tend to lose a few psi per month, so make it a habit to check them frequently and keep them optimized.

3.-  GASOLINE

The lower the octane, the cheaper the gas, but does it save you money?Porsches in particular have higher compression engines than the larger displacement engines in domestic cars.  This higher compression requires higher octane grade in order to eliminate knocking.  Newer cars have knock sensors that retard the ignition to avoid knocking if a lower octane gas is used, but this makes the car less efficient, and in the end it uses more gas to drive the same distance and ends up costing you more.  Check your manual or the sticker inside the gas lid for the recommended octane rating for your car.









A lesser known tip is when to purchase your gasoline.  Buy it during the coolest part of the day.  Evening or early morning is best.  The lower the gasoline’s temperature the denser it is, meaning that a gallon of cold gas weighs more than a gallon of warm gas.  Gas pumps charge you by volume not by density.

4.-  MAKE IT LIGHTER

We all know that making a car lighter will make it go faster, but it will also save you gas.  So, check your trunk(s) and clear them as much as possible of the stuff you don’t need which will translate into savings at the pump.

6.-  A/C or AL FRESCO?

The air conditioner, unlike the heater

which uses the engine’s “free” heat to

warm you up, uses the engine’s power

to run the compressor, thus lowering fuel

economy. 

But if you’re driving on the highway, sometimes it’s better to close the windows and run the A/C.  Why?, Because of aerodynamics.  The detriment from driving with the windows down is greater in a Porsche, which has excellent aerodynamics, than in a Hummer, which has ... none!  The same applies to cabriolets.  You’ll get better gas mileage with the top up.

7.-  MOTOR OIL

Use the correct grade of motor oil specified for your vehicle. 

Following the factory’s recommendation can improve your gas mileage by 1-2%. 

The recommended oil and oil grade is specified in your car’s manual

8.- DON’T IDLE

Shut the engine off if you expect not to move for a while.  When a car is idling, it is giving you zero (0) MPGs.


9.- WARM UP

Avoid prolonged engine warm up.  Even on cold mornings 30 seconds or so is plenty of time, but never fully accelerate an engine until it reaches its operating temperature.

10.- PLANNING

Plan your trips.  Combine short errands into one trip using the shortest distance possible.

Following these tips you can easily gain 2-5 MPGs, guaranteed.


Here’s an interesting exercise:

If you drive an average of 15,000 miles per year and get 20 mpg, you will have used 750 gallons of gasoline.  At $3.50/gallon that’s a cost of $2,625.00/year, or $0.175/mile.

If you’re able to squeeze an extra 4 MPGs, that’s an extra 3,000 miles! 

(4 mpg x 750 miles = 3,000 miles).

At $3.50/gallon you just saved $525.00.

($0.175/mile x 3,000 miles = $525.00).


To learn more about saving fuel and your Porsche in general, please visit my website at: www.PedrosGarage.com.


Happy Porscheing,





Ⓒ2012 Technolab / PedrosGarage.com

MPGs                                                        by Pedro P. Bonilla GCR PCA

5.-  LIGHTEN THE LEAD FOOT

At the track you shouldn’t be worried about gas mileage, but in the city, you can save a lot of fuel by accelerating lightly.  Full throttle acceleration is a sure-fire way to drop your average MPGs.

Most cars’ fuel consumption reaches maximum efficiency at 55 mph in it’s highest gear.  Wind resistance increases exponentially with speed, so as your pace quickens, your gas tank starts to dry up faster.  Each 5 mph you drive over 55 mph can lower your gas mileage by 7% or more!  Look at your instant fuel consumption gauge (if so equipped) and that’ll help you drive in a fuel-saving manner.

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