Attitudes about altitude






Old-car lovers sometimes make dumb mistakes, but being afraid to drive your old car at high altitude does not have to be one of them. After all, altitude is relative.


After living in Denver most of my life, where it is an average of 1 mile above sea level, I have a different view as to what is “high altitude.” My body has adjusted itself after all of these years. However, a fact of life is that our old cars won’t adjust themselves. We have to do it for them.


Those of us who live in the Rocky Mountain Region don’t think anything about the altitude. We are used to it and have adjusted our lives (and cars) accordingly. There is really no secret to how we do this; it is mainly common sense.


Many of you reading this article from other Regions will be coming here to Denver for the 2001 Grand National and don’t want to bring your old car because you are afraid it won’t run or start at Denver’s altitude. Your car will actually run better than you expect and a minor adjustment that I will talk about later will even improve that. If you plan on driving one of our mountain tours, a little more adjustment may be needed.


No matter what you do, your car will have a little less power than it does at lower altitudes and sea level. This is true with “modern iron,” too. It really can’t be too bad, however, or all of us who live here would be walking, riding bicycles or using horses instead of horsepower. It may surprise some of you, but there are cars, buses and trucks here and we do just fine. (Even the Indians are friendly.) When people from this altitude go to a lower altitude for vacation, the amount of additional power is very noticeable in newer cars as well as our older ones.


Let’s go over a few things that will make life a little easier for your old LaSalle or Cadillac at this altitude, starting with coolant. Make sure your cooling system has the proper mixture of antifreeze and pure water. A 50/50 mixture is ideal for all climates, even tropical. On the older cars that are not equipped with a pressure cap it will help to install a 4-pound or 7-pound cap. Make sure you get one with the proper depth. This minor modification can raise your boiling and overflow temperature as much as 20 degrees. Also you may experience a little more expansion of coolant, but don’t worry about it.


Your ignition timing is probably the most critical and the easiest to adjust for altitude. The reason being is that in thinner air you have a little less compression pressure causing the fuel mixture to burn slightly slower. To compensate for this, your timing should be advanced about 8 to 10 degrees. On the old flatheads, this can usually be done at the fine tuning adjustment that holds the distributor down. Just loosen the quarter-inch bolt on the front of the distributor tower and rotate the upper section counterclockwise to the stop, or 10 degrees more than you have it set at for lower altitude.


If you don’t have this much adjustment left, you may need to reset the timing with a timing light using the timing mark on the pulley. Set it between the timing mark and the “I” in the IGA mark. You can tell you went too far if, when starting up, you experience a little “kickback.” This quick little adjustment not only will make your car have more power at highway speeds, but it will run cooler, too. When you get back to a lower altitude, you may want to set it back if your car seems to be a little harder to start.


As for carburetor adjustment, you may not need much, if any, for a short stay. If you have a Stromberg carburetor, you may want to check the jets and make sure they are no larger than .050 and preferably .048. You may find that when you return to a lower altitude, your car will run better, but possibly a few degrees hotter.


Tire pressure at a cold 32 psi at lower altitude will read about 34–35 psi at this altitude. This should cause no more problem than a little stiffer ride and better handling on mountain curves. If you do change your tire pressure, be sure to change back when you get to a lower altitude.


So much for your car; how about your body and all of this talk about “high altitude sickness?” Actually, unless you engage in strenuous athletic activities, you won’t feel much difference in Denver’s altitude. You may sleep a little better and tire out a little bit quicker. Be sure you drink a little more water. Our sports teams give a lot of hype to this high altitude and thin air thing, but it is more a scare tactic than factual.


If you take our trip up to Georgetown and/or up Mount Evans, you need to be a little more cautious. Even our natives feel the difference at 10,000 feet. Just don’t overexert and don’t forget to take extra water to drink. Be sure to take a jacket, especially if you want to play in the snow.


The biggest problem we have is after a trip or two to our area, so many people find they like it so much, they end up moving here. Not only that, there is so much to do and see here that many longtime residents still have many new adventures yet to do.


See ya next month.