Author: ltradmin

Link to article by Bob White.

Here is another technical article by Bob about his Ruf RS America

Two-part article published by Bob White about tires.

From the Driver’s Seat by Chuck Tucker ©2005 – Whoa

I’m just back from instructing at Mid-Ohio, where I was surprised by the results of a braking exercise we did with the first-time students. These students were hard-driving, autocrossing, gas-pedal-loving Car People – and none of them had any idea how hard they could really apply the brakes. Braking is a very useful skill. Being able to slow the car quickly, under control, gives you options that other driver’s don’t have. The goal is to make the wheels rotate about 15% slower than the car is going, but not to lock the wheels and slide. There are three elements: managing weight transfer, knowing when to let up, and braking straight.

If you jump on the brakes suddenly, putting full pressure on the brake pedal immediately, you will lock up the front wheels. Instead, build pedal pressure on the pedal gradually. As you apply the brakes firmly the car will begin to slow, weight will transfer to the front wheels, and the nose of the car will drop. Once this has happened, squeeze the pedal harder. With more weight on the front, you can use more pedal pressure without locking the wheels. This whole process, from first touching the brakes to full pressure, will take at least a second. It often feels like braking twice: press once to put the nose down, then press more to really slow the car.

If you press the brake pedal hard enough to activate the ABS, and you really need to stop the car, don’t let up. The ABS is doing at least as well as the best you can do, and you should let it finish the job. If you’ve never felt your ABS activate before, find a smooth, straight empty road or a big parking lot, get the car up to about 45mph, and stomp the brake pedal as hard as you can. Most ABS systems make a harsh buzzing sound and vibrate the brake pedal. Learn what that feels like, so that you don’t let up on the pedal, thinking something’s wrong, when you should be pressing it to the floor.

If your car doesn’t have ABS you may occasionally lock up a wheel. A locked wheel give a peculiar feel to the car that you’ll learn to recognize, and a characteristic sound. Suppose that 100% represents the perfect braking pressure, but you applied 110% and locked up a wheel. You need to reduce the pressure to about 75 or 80% to get the locked wheel rolling again, then squeeze down closer to 100% to slow the car. If you want to practice this, a wet parking lot is easier on your tires than dry pavement and will let you do the whole thing at lower speeds.

Finally, you can brake hardest when the car is going straight, and you cannot turn the car when braking at maximum pressure. I’ll explain why next month. Until then, keep your eyes up, drive safely, and enjoy.

From the Driver’s Seat by Chuck Tucker ©2005 – A Look Ahead

Eight years ago, my friends talked me into attending a PCA driver’s education event at the Putnam Park Road Course. In the classroom I heard that 70% of Americans consider themselves to be above-average drivers – but of course they aren’t. On the track I found that driving fast is much harder than it looks, and loads of fun. I got so hooked, I now instruct at PCA events. In From the Driver’s Seat I’ll share some of the lessons I’ve learned from the track. These tips can help you at the track, but they are primarily intended for every day driving on the street. I hope that they will make driving your Porsche more fun.

The first tip is this: look ahead – way ahead! Too many drivers lock their eyes and their brains down just a short distance ahead of the car. Often their attention span ends at the bumper of the next car, which they are probably following at some NASCAR-inspired distance you could measure with a ruler. When something unexpected happens – the car in front brakes hard, the light turns red – these drivers are surprised, unprepared, and often on their way to the body shop.

Good drivers look ahead. The good drivers at the track look surprisingly far ahead. They plan the path they will take around the next turn, spot potholes and slick spots, predict how the traffic will develop and position themselves to deal with it. They scan for potential dangers (Is the car rushing in from the side street going to stop?) and allow themselves room to avoid them (I’ll ease up on the accelerator until I see him begin to slow).

Familiar advice from driver’s ed is to imagine a piece of tape running horizontally across your windshield, halfway between the upper and lower edges. You should spend most of your time looking above the tape, and only glance below the tape from time to time. If you are going 60 miles an hour and your reaction time is 0.7 seconds, there’s no point in looking at anything closer than 60 feet in front of you (about four car lengths); if it suddenly changes, you can’t react before you hit it. By keeping your eyes farther out, you see things that you have time to react to. By looking much farther out, you see them when a small change in brake, throttle or steering will take care of them.

The next time you are on a curvy road, look as far ahead as you can. Keep pushing yourself to see around the next bend, even when the trees are in the way. The next time you are on the highway, try to look half a mile ahead. See the traffic patterns, predict how they will develop, and make lane changes that allow you and your fellow travelers to move smoothly up the road. The next time you have to follow close behind another car, look past them, or even through them (if their windows are clean), so that you can see what is happening ahead. As you look farther and farther ahead, you’ll be surprised how, even when you are driving quickly, events around you seem to slow down and become more manageable. And your driving will be smoother, safer, and more fun.

From the Driver’s Seat by Chuck Tucker ©2005 – Connecting

Last month I talked about looking ahead. Keeping your eyes well out in front of the car will allow you to anticipate events, and help you drive a smooth, controlled line. This month we’ll start on basics of car control. The first step is really basic: sitting in the seat.

Try this exercise. Take your car to a large, empty parking lot, and do some slaloms and U turns. You don’t have to go fast – 20 mph will be plenty – but turn hard enough that your tires start to make a little noise. Now notice how you are sitting as the car turns. Many drivers lean forward just a little bit to get good leverage on the steering wheel, bringing their shoulders away from the seat. This is bad. It requires that you use your hands, arms and the steering wheel to hold your upper body in place. You will drive better if the seat holds you in place, so that your arms only have to steer.

To find a good seat position, start by connecting your body to the seat. Burrow your bottom down into the seat bottom, and snuggle your back into the seat back. Keep this connection, and start adjusting the seat. Slide the base far enough back that your feet can easily move among the pedals, but far enough forward that you can press the pedals all the way to the floor. Then, with your shoulder blades touching the seat back, straighten one arm and lay it across the top of the steering wheel. Adjust the seat back so that wheel touches somewhere on your palm, between your wrist and your fingers. For street driving I like to be on the far end of this range, but I sit an inch or two closer to the wheel for track driving. You want to have good leverage on the wheel, with your arms slightly bent, but not be so close that you can’t steer quickly. If your car has an air bag, your chest must be at least ten to twelve inches behind the steering wheel. It may take a bit of fiddling to get all of this just right, so take your time. When you’ve got the seat adjusted, don’t forget to re-set your mirrors, and of course fasten your seat belt.

Now go drive the slalom again. Keep your body down in the seat and your back against the seat back, letting the seat support you. Imagine that you have five-point harnesses installed, so that the shoulder straps are holding you tightly against the seat back; that’s exactly why many autocross and driver’s ed drivers install harnesses. As you get used to sitting in the seat, rather than on it, you’ll find yourself more relaxed in the car, even under heavy cornering. You will focus more on driving the car, and less on keeping yourself in the seat. Best of all, you will feel more of what your Porsche is communicating through the seat and the wheel – which, of course, is half the fun.