Letters from readers, March 1943
At the Brains Trust someone raised the hoary question as to whether it is a bad thing to brake when cornering. Mr. Pomeroy pointed out that the application of brakes on a bend may tend to promote an over-steering characteristic (this, of course, would particularly apply with a torque tube or radius arm lay-out), but otherwise the discussion was not carried very far. It is, nevertheless, an interesting one, and it would be instructive to learn the views of experienced drivers.
I think it probable that the adage about not braking when bending dates back to the days of loose road surfaces, thin tyres and rear-wheel brakes. To apply the brakes under such conditions meant a rear-wheel skid, which is bad driving, because its correction wastes time. In very skilful hands, however, this characteristic of early braking could be put to powerful effect; for by locking over rather before the corner, and clapping on the brake, the car could be thrown into a broadside, continuing to motor sideways towards the corner. In this way it was miraculously endowed with the effect of powerful four-wheel brakes and slowed up rapidly; it also arrived in the corner already pointing in the right direction for a rapid departure without more ado. Contemporary literature suggests that Bruce-Brown was an early exponent of this technique, and Archie Frazer-Nash put it to powerful effect in hill climbs of the early 1920’s.
Another invaluable use of rear-wheel brakes when cornering lies in their ability to correct an unexpected front-wheel skid. This was well known to Frazer-Nash owners, and I have found it most useful on the Itala. For this reason I think it most desirable that the hand brake should operate on the rear wheels only.
With modern road surfaces, fat tyres and four-wheel brakes, there seems to be little objection to braking when negotiating a corner under normal circumstances; but if the corner is being undertaken at the limits of adhesion, any strenuous application of the brakes will remove the margin of safety, and the vehicle may go skating off at an inconvenient angle. The conclusion, therefore, appears to be that it is quite safe to use the brakes when cornering, provided that they are not going to promote a skid.
Almost under the same heading as braking when cornering comes the use of the accelerator when cornering. Mr. Lowrey recently expressed a preference for accelerating round a corner, but I think that if this is carried to its logical conclusion it will be found to be a bad thing. Given a sufficiently powerful motor car, acceleration in a corner will have just the same effect as rear-wheel brakes—it will dis-adhere the back wheels and promote a side-slip.
It seems to me that it is only bad driving to skid one pair of wheels independently of the other. Either a front or a rear wheel skid puts the car out of position, and therefore needs correction, and this wastes time. If one is arranging to traverse a corner beyond the speed at which the tyres will continue to hold on to the road surface, it is essential to lose all four at once, and to an equal extent. To do this on a car with a lot of over-or under-steer is difficult, but on a properly balanced lay-out the car will then go round the corner in a steady “drift” (the nose pointing to the inside of the bend, and the front wheels rather more so) which needs no correction, and therefore wastes no time. The amount of acceleration desirable, and the extent to which the front wheels have to be pointed to the inside of the curve, will, of course, depend on whether the car is inherently an oversteerer or an understeerer.
I wonder if these views would be generally accepted.
I am, Yours etc.,