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Front and rear wheel drive

Dare points to a Slate story about front and rear wheel drive, titled “Why Front-Wheel Drive Sucks.” There are a couple of points in the story about oversteer and understeer that I want to address, as they’re a bit misleading, in my opinion.

First, he makes sweeping generalizations about front or rear drive cars and their handling balance. There are other variables which are in some cases even more important - like where your engine is. Mid- and rear-engine cars will tend to oversteer more than front-engine cars; it’s all about inertia and weight transfer.

He talks about how to recover from a understeer vs. oversteer skid, and mentions that you have to turn the wheel the opposite direction in each case. Well, as a race driver, this is way too hard to remember - when you’re at the limit in a car, and you start to skid one way or the other, you don’t think to yourself “hmm, ok, oversteer, turn the wheel in the opposite direction, right?”.  There isn’t time - it’s instinct. Here’s the secret - if you’re in a skid, whether understeer or oversteer, look where you want to go. Let me say that one more time, because it’s so important - look in the direction you want to go. Your hands will naturally turn that way too, and you’ll be doing the right thing.

If you look at the wall, you’ll hit the wall. Seriously.

So now that we’re steering the right way, we have to figure out what to do with the gas as well, and this is where there’s a valid point to be made in the article, but he doesn’t get it quite right. If you’re understeering (driving off the edge of the track/road), you need to lift off of the throttle a bit. This will shift more weight to the front wheels, which increases their grip, which will bring the nose back in. Don’t get crazy with the lift - too much and your understeer will become oversteer before you know it. So far so good - lifting is intuitive for most people in a skid.

If you’re oversteering (rear end is sliding around), it gets more interesting. Let’s consider a non-power oversteer, which means you didn’t induce the oversteer purposely by mashing on the throttle. The rear end is of course sliding because it doesn’t have enough grip. If you lift in this situation, weight transfers to the front of the car, from the rear. The rear tires now have less weight on them, which means they have LESS grip, which makes the problem worse. You actually need to give a little bit MORE throttle in this case - transfer more weight to the rear wheels, they then have more grip, hopefully enough to drive out of the skid. And you’re looking where you want to go, and you’re turning that way too.

The article says of rear-drive cars:

“But you can still feel the front end starting to plow wide a bit. What to do? Step on the gas!”

Well, this might happen when you’re driving to the grocery store, but if you’re anywhere near the limit, behaving like this is guaranteed to drive you right off the track. Don’t do it!

Any comments? I love driving, and talking about cars - it’s much more fun than working. :-)

This post is licensed under CC BY 4.0 by the author.