One of my earlier points is as below. I expected some ??
I got the idea from Pat Prince @ Prince Race Car Engineering...keeper of the
flame under Tom Robertson's venerable 7 efforts and probable 1997 run-offs champ
:-). Also, later found same point in an article by Carroll Smith:
Quote:
CORNER ENTRY UNDERSTEER - car won't point in and gets progressively worse
excessive front tire pressure
insufficient front track width (compared to rear)
excessive front roll stiffness
front roll center too high or too low
insufficient front damper bump force
insufficient front downforce ( gotta change the angle of the clamshells;-)( MN)
excessive dynamic positive camber on laden (front) "tyre"
braking too hard and too late
* Insufficient front roll resistance--car may be falling over onto outside front
"tyre" due to insufficient front track width or diagonal load transfer under
trail braking Understeer can often be cured by increasing front roll resistance
even though doing so will increase the amount of lateral load transfer.
________________________
In the case of running outa bump travel; that appears to be a real problem with
the front suspension on 7s where they have been lowered. One would need a
shorter damper. If the car initially points then washes out, it could be
indicative of hitting the bump stops.
Marc Nichols wrote:
> I also found that my 7 was "falling on the front end" at turn in. =
Stiffer front
> springs actually improved turn in and balance.
Oooh boy. Now that is a really subtle one. A stiffer front bar =
*improved* the
turn-in? Wow, that is counter-intuitive, or maybe my poor little brain =
just can't
comprehend all the things that may be going on at the same time, during =
your
car's turn-in transition.
OK, here's a blind stab. Could it be that before, when you were "falling =
on the
front end" you were in fact, hitting the bump stops and thus abruptly =
washing
out the front end. Stiffening the front springs oughta *increase* front =
end load
transfer and thus promote push, but maybe this is moot, if hitting the =
bump
stops were causing a more sudden and dramatic problem?
!^NavFont02F06D8000ChI59HI78HMD90C39
Cheers!
E mail from Marc Nichols; Age & Treachery Racing, Ltd., Los Angeles
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