FEATURE ARTICLES

More Miles Per Gallon Per Classic Car Show

By John Gunnell

Don't let pricey gas ruin your hobby this summer. By doing some routine service, practicing good driving techniques and planning ahead, you might be able to keep fuel costs affordable and attend as many shows as last year.

This summer you will have more fun with an old car, like this '36 Pontiac, if you take some basic steps to maximize its operating efficiency to save gas.

Maintenance

We know that a well-maintained car will run better and more efficiently. A tune-up provides peak efficiency. The spark plugs, points, rotor, condensor, distributor cap and timing should be taken care of. Adjusting the carburetor is very important. An overly-rich air/fuel mixture can kill fuel economy.

Properly adjusting the mixture and idle speed screws on this vintage Stromberg carburetor will prevent an over-rich mixture and control fuel flow.

Check the vacuum fuel pump on your vintage car for signs of leakage. Some modern gasoline will eat through old diaphragm material. In addition to wasting gas, a leaky fuel pump is dangerous. Get a rebuilt pump or a pump rebuilding kit with a modern diaphragm material that's unaffected by today's gas.

This brand new AC fuel/vacuum pump for a '51 Buick will likely leak modern fuels and should be rebuilt with updated seals and diaphragms.

Recently, a group of hobbyists taking an automotive night school class were offered the use of a Motor Vac Carbon Clean machine. This has a small fuel tank that holds a gallon of gas and a solution that cleans carbon from an engine. The teacher said cars get three to five more miles per gallon after a Motor Vac treatment. The procedure takes and hour. Repair shops charge up to $150 for it. The high school shop does it for student practice and charges $10 (cost of the cleaning solution + gas). You may find a school offering it near you.

New ignition parts such as these points, distributor cap and rotor will help achieve more complete fuel combustion and up your old car's fuel economy.

The correct amount of air in your tires and proper wheel alignment decrease road resistance and increases fuel economy. Check tire pressures each time you leave for a show. Tubeless tires arrived around 1955. If you are using tubeless tires on a car with non-tubeless rims, you may get slow leaks. Rotate your tires and check and reset your wheel alignment regularly.

Filling your tires to the correct air pressure was just as important to good fuel mileage in 1942, when this photo was taken, as it is today.

Sensible Driving Practices

It pays to drive sensibly. Accelerating quickly or stopping on a dime wastes gas. Such driving practices can lower gas mileage by 33 percent at highway speeds and by five percent around town. Sensible driving is also safer.

Don't speed. Fuel economy decreases at speeds over 60 mph. Most vehicles get optimum mileage at 35-45 mph. You pay 10-cents per gallon for every five miles an hour over 60. At 60-plus fuel economy drops 7-23 percent.

Avoid idling your engine. Idling is the same as driving and getting no miles per gallon. Monster mills waste more gas at idle than four bangers. When your muscle car ain't moving, shut it off. Avoid the driveway "warm up." Instead, drive slowly for the first few blocks to bring your engine up to operating temperature.

Shift properly. Many older cars, sports cars and muscle cars use manual transmissions. Shifting into high gear as soon as possible, without lugging the engine reduces drag and uses less fuel. On cars with automatic transmissions, stay out of lower gears and avoid using the "kick-down" gear to show off your car's acceleration.

Many older cars had overdrive. Use it. When you use overdrive gearing, your engine speed goes down and you save gas. Cruise control is rarer on old cars, but should be used when available. Using cruise control helps maintain a constant highway speed, which usually saves gas.

Packard was the first automaker to offer air conditioning in the 1940s. By the '60s it was becoming a more common option. Today, it's rare to find a vehicle without it. The older air conditioning systems aren't as efficient as the ones today. With the air conditioning on, your old car's engine uses more fuel. You can increase gas mileage tremendously by using the A/C only when really needed.

The way you drive your car has a strong influence on fuel economy. A light touch on the accelerator, proper gear shifting and route planning save gas.

Plan Ahead

Planning can increase fuel economy, whether it's plan-ahead driving or spending more time planning your route to a car show. By thinking about what's coming up, you can anticipate moves that might waste gas and avoid them.

When driving, think about that red light ahead. Take your foot off the get and let your vehicle coast to a stop. Use the vehicle's own momentum to get you to the intersection. If you know that a big hill is coming, increase your momentum before you start up the hill, rather than gunning the accelerator near the top.

These days you can do a really good job of planning your route to a car show. Computer programs like Map Quest or online planning services like Map Quest can print you out turn-by-turn instructions from any starting point to any destination. Many times you can pick the quickest route, the shortest route or the most scenic route. Usually, the shortest route will use the least gas.