Hi again Jerry (and Bea?)!
How are
you going to set up your suspension for both autocross and rallycross? Kind
of opposite ends of the suspension spectrum, no?
Surprisingly not. I have a set of STI struts on the car now. They did
lower things a bit; maybe 1/2 inch, but they work super on bumpy/rutty
dirt roads at speed. The chassis stays fairly flat, and tracks like
it's on rails. Larger bumps, rocks, and washboards just disappear into
the suspension without altering the trajectory much, if any. In fact,
I'd say the WRX is a far better offroad/rallycross tool than an
autocross car; not too surprising considering it's origins. I have
installed a factory rear diff protector, an aluminum skid plate under
the engine, and huge mud flaps. Everything else is pretty well tucked
in, and not too likely to sustain crippling damage from chance
encounters with terra firma. I have picked up a few bumps and scrapes
to the underside, but mostly from taking the car over jeep roads goin'
fishin' (where it works amazingly well, all things considered, and you
wouldn't believe the looks you get from the 4X4 crowd ;-)
For autocross, the superior tracking provided by the AWD makes it
difficult (at least for me) to get that last little bit out of the
tire adhesion; it slips into understeer so transparently that it
encourages application of more throttle, especially in sweepers. While
this feels fast, and is huge fun, it's just _not_ the fastest way
around. On dirt, OTOH, you are always drifting (if you're going fast),
and then the AWD system works for you in a big way, helping to keep
you on track even if you get overly enthusiastic with the go pedal.
In all honesty, I have mostly been driving my well sorted little MR2
in CSP this season, with my 16yo daughter as a co-driver. It's
probably not as competitive in it's class, but it's simply more fun to
autocross, and fun is the name of the game as far as I'm concerned.
Plus the girl-child is a beginning driver, and I want her to learn to
work the RWD car first, as it demands more precision from the pilot.
Once she gains some proficiency/consistancy in the MR2, I'll turn her
loose with the rex.
I'll mention that I do disable the WRX ABS for aggressive driving
(especially on dirt, snow, and ice), as it's way too sensitive. Bumps,
washboards, and slick surfaces have it activating as soon as you touch
the brake pedal, which dramatically reduces the amount of braking
effect. This is a good way to explore the ditch on the outside of the
turn, or to give the course workers something to do!
Finally, rallycross, at least as sanctioned by the local SCCA group,
is pretty much just an autocross on dirt; either a large dirt parking
lot, or the south forty on Doc's farm (literally). Ruts, grooves, and
loose berms do form after the first couple run groups, but basically
the courses are pretty smooth, and tighter/slower than your average
autocross. Dust is often a bigger issue than anything else. We had
several rallycross events on ice last winter (my favorite; I actually
get to win sometimes), but I've been told that the property owner got
upset when some fool burned a couple donuts in their field, and may
not allow us access this winter.
Bummer.
ByeBye! S.
Steve Jernigan KG0MB
Laboratory Manager
Microelectronics Research
University of Colorado
(719) 262-3101
