rfn026

The concept of improved handling is very elusive. I'm back doing some work for Corvette Fever magazine and thought I might share some of the early drafts here on the Corvette Forum.

There are 5 things involved in handling:

Response
Precision
Gain
Progression
Balance

I elaborate on these five concepts in my Blog. I would love to hear from you on these five items.

Richard Newton
Autocross Performance Handbook

VetteDrmr

Richard,

First off, I really enjoy your writings in CF (Vette as well? I subscribe to both). I'm not national or regional material, just a guy that loves to autocross his Vette on a fairly limited budget.

There's one thing that I think you might consider: feedback. Primarily through the steering, it could also be the car's response that we feel through the seat.

Thoughts?

Have a good one,
Mike

Solofast

In your discussion you have missed force gain.

That is, the relationship between steering force versus lateral G. The onset of power steering boost and the slope of the force gain curve is what is important here. If the onset of boost is high (a common trick to get more "road feel" into a power steering system), then the car will feel heavy. If it is too low, the steering system will lack road feel on the straights.

This is a very important aspect since it is one of the key feedaback parameters in terms of the car telling the driver how hard he is pushing it. It effects how the car feels (sharpness) and what the car is telling the driver during cornering. Also, as you increase the lateral acceleration to beyond the peak, a really good steering system tells the driver that he is over the top by getting lighter, and with that the driver actually learns to back off on steering angle to maintain maximum cornering speed.

I had a RX7 (first gen) and with the manual steering there was a large increase in force with increasing lateral aceleration. On the straights, even without power steering there was actually lower steering effort to make slight corrections at speed. As lateral acceleration increased the steering effort went up faster (the slope of the effort vs G curve was steeper) and that made it a lot easier to know how hard you are pushing the car.

When I got my first C4 the first time I drove it on the highway my arms ached because the on center steering effort was higher and I wasn't used to it.

While most cars have an increase in effort vs lateral acceleration, the threshold is high (due to having power steering) and the slope is relatively flat, so that the steering effort doesn't get too light at speed.

As an aside, GM has recently figured out why BMW's have such great steering. They took one apart and found that BMW's have a very low residual friction in the steering system, which lets them have less boost and it doesn't mask as much the effects of force gain. That is, they could run more caster and get more force gain, while preserving lower speed parking effort. The result is lighter steering on the straights and a steeper force gain curve during cornering, and thereby a "sharper" less numb feeling to the car...

This is also why a Porsche feels so good, since there isn't much weight on the front wheels, they don't need a lot of power steering boost, and that allows them to have better steering "feel", a lower threshold of power steering onset and a steeper force gain curve.

anotherone

From one who is just reading thanks to all ; very informative.

0Randy@DRM

That was a very good read. There was a lot of info on steering feel and the feedback the driver feels with some good terms. Are you going to be getting into the other parts of "handling"?

Randy

C5inWV

I just got back from a weekend at Summit Point. My brakes were great and I had plenty of power, but my handling sucked. What I mean by this is that the car didn't transition well from braking to turning to accelerating past the apex. (Stock Z51 suspension.) I had to wait for the car to settle before I could get hard into the gas.
So I would like to say that a good handling car transitions well from one driver input to the next.

rfn026

There's a whole lot of BMW thinking in the C6 Corvette. Dave Hill once explained to me how the C6 was different from the C5. I looked at him and asked "What else have you copied from BMW." There's a reason he never liked me.

I'm going to get into a whole lot of handling issue in the future. Right now I'm just cleaning the old '85 after my weekend at Sebring. I've done a lot to the rear suspension with a combination of Rippe and Vette Brakes stuff. The amazing thing is that all of it actually works. My problem now is that I can get on the power so much earlier on the exit of a corner I'm having to learn how to drive all over again. Some friends would say using the word "again" might not be the truth.

btw - i love the fact that we can actually discuss some of the ideas here. When you write books and articles it's like sending words down the black hole. I just love all the comments and suggestions. The interactive nature of these forums is great.

Richard Newton
Autocross Performance Handbook

Fastguy

Not sure where this fits in but the way the car reacts to elevation changes and also how it functions under compressed suspension plays a major part in how quickly you get around the track.

bobmoore2

It seems to me that you all are talking about handling FEEL, that is, how the car feels as it approaches, reaches and exceeds its limits. Don't ignore the handling LIMITS or performance limits, which looks at things like maximum cornering Gs, braking distance, accelleration, etc.

It seems the concensus here that the BMW has better handling feel. (I can't comment, because I've never driven one.) However, the Corvette is still faster on the track, because it has higher handling limits. So this would indicate that the Corvette is a better handling car.

Am I out in left field or on the right track with this train of thought? (Sorry about all the cliche's.)


Another point of view when looking at handling is the application the vehicle is intended for. The best handling car at Indianapolis Raceway would be the worst handling car for the Baja 1000, and vice versa. When the application is autocrossing or HPDEs on a road track, then the Corvette is an excellent handling car. When moved to the street, the Corvette's handling is not as good, because it does not like rough, damaged pavement and its ride is too harsh for the average driver. On dirt roads or off road, the Corvette is terrible.

Comments, please...