From: Brad Cox <coxb@trimofran.org>
>What this driver suggested was that I set the rear shocks at their lowest
setting, and set the front shocks >at near their highest (stiffest) setting.
Their premise was that this will "plant" the front wheels, and >if I
encounter understeer, then throttle out of it. Well, this is basically the
opposite of what I have >been taught.
Of course it is basically the opposite of what you have been taught. Because
it's nonsense. I have been driving FWD cars sine 1969, and have yet to
successfully use power to get out of understeer.
>I know that to induce oversteer in a FWD car results in a "sacrifice" of
sorts,
In and autocross environment, what are you sacrificing? You want the car to
oversteer off-throttle and understeer slightly on-throttle. Most "untuned"
FWD cars understeer under all throttle conditions. Not the setup for fast
autocrossing.
>I started thinking maybe I shouldn't be using the shocks to help with
oversteer at all, and that's what >they were talking about. But at this
point, the shocks are all I have to work with besides tire pressure. >Right
now, my car does not have front or rear swaybars. The sway bars I'm about
to purchase, combined with >my spring rates, should provide enough oversteer
so that I don't have to depend on shocks and tire >pressures for it.
That's good. But don't sell tire pressure short. What always worked the
best for me is to get the front to stick as well as possible, then
over-inflate the rear tires until I get balanced handling.
Some people would rather under-inflate the rear tires to achieve balance,
but I hate the mushy feeling and the sometimes snap changes in balance. I
find over-inflating the rears gives a much crisper, more linear response.
>So, what I need to do is let the springs and sway bars provide the
oversteer, and use the shock settings to help "plant" the front wheels.
This isn't exactly what they said, but does it sound right???
If you are able use spring and swaybar changes (Street Prepared) you want to
use them to achieve balance. Shocks should be stiff enough to control
bouncing. Making them harder is not a real gain, especially on rough lots.
I have always thought of very hard shocks as something Stock Category folks
have to do, because they are not allowed to tune the suspension the right
way, with the spring & swaybar rates.
I'm sure there are folks who can fill you in on the fine points of
Street-Prepared shock rates. I'm not one of them. I know that you should
use the springs & swaybars to tune the steady-state balance and THEN shocks
to tune the transitional response.
Phil Ethier Saint Paul Minnesota USA
1970 Lotus Europa, 1992 Saturn SL2, 1986 Chev Suburban
LOON, MAC
pethier@isd.net http://www.visi.com/mac/
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