This reminded me of the rises and falls of some race tracks and the need to analyse each corner to decide which ones need the most care and attention in order to get a better lap time. If you have a corner with a long uphill straight after it, like Hell Corner at Bathurst or the sweeper at Hampton Downs, then getting the maximum possible speed through it is vitally important for a good lap time. These are the corners that need to be analysed and concentrated on. Being just a few kays too slow at the exit of these bends will kill your lap times as you just can not make up the speed as easily on the uphill straight. Downhill corners followed by shorter straights, like the Fox Hole section of the ring or the Corkscrew at Laguna Seca are less critical. Your car will quickly reach its maximum speed along such small straights anyway, so a slower corner exit can be recovered more easily.
How does all this relate to the real world as we trudge along on our daily commute or the drive to the beach?
With a bit of practice you can anticipate the hills ahead by increasing your speed gradually as you travel along the flat. That way your momentum might just help up the hill without needing any extra acceleration. Once at the crest of a hill, you can then squeeze the gas pedal a little more to rebuild the speed with a minimum amount of energy. If you can then lift off the gas completely on the descent you are literally on a free ride and your fuel economy will improve.
Think of how your cruise control works. Naturally the car can’t ‘see’ down the road like you can. It will wait until the hill starts and then blindly strive to maintain the set speed, even until you are past the peak and over the other side. Some late model systems will even brake on the downhill part to bring you back to the target speed. It’s all quite wasteful, simply because the system can’t look ahead to anticipate what’s required. I’m yet to try one of those new sat-nav linked cruise systems however.
Obviously if you have a line of traffic behind you, big fluctuations in your speed will drive everybody nuts, so moderation is required. If you practice this enough you can also start to anticipate intersections ahead by lifting off early and coasting for a while before you need to brake to a stop. It really doesn’t take much to do but it does pay you back when it’s time to go back to the pump. The interesting thing is, you will notice that your average travelling speed is barely affected. Something for nothing is always a bargain.