Objectively measuring and defining subjective steering "feel"

[vcebrad]

I recently read an article on the new C6 Corvette and noticed GM got high marks for many things, but steering "feel" was not one of them. Many of the BMW's, especially the previous (mid 90's?) model M3, are widely touted as having nearly perfect steering.

What is it about steering system design parameters that make that tiny difference and push a great car into the realm of the nearly perfect? Are there books out there on automotive steering system design? Are there experts who make fortunes at BMW, know enough to write the books, and are impossible for GM to lure away? How does one objectively measure and design in a certain steering feel, when it seems to be a subjective criteria?

 

[GregLocock]

That could be due to a whole lot of different reasons, in no particular order, and not a complete list: tyres, suspension geometry, RWD or FWD or AWD, boost curve, friction, suspension calibration.

It may even be a deliberate choice.

Typically I find AWD cars have lousy steering feel, but are quicker, thereby demonstrating that the ability to feel what the tyre is up to is not necessarily the most important thing.

One of the more reliable indicators that you are approaching the limit of the tyre is that the SAT gain drops off, or in other words, the pneumatic trail reduces. But you should bear in mind that through the wheel you are feeling the total force due to both tyres, so the inner tyre can mask what the outer one is up to.

Cheers

Greg Locock

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