Newbie Q, tuning for max speed

[Damon Gentile <dgentile-at-spf.fairchildsemi.com>]

Hey folks, a couple of newbie questions here. Hopefully nothing too
dumb, I've been struggling with these for a little while now.

BDI 2.18 & PII 333MHz 64MB ram, running EMC_MINI with freqmod.o
with four NEMA23 116oz/in steppers. Only 12V for the moment.

I've tried a bunch of combinations thus far and think I'm doing
pretty good.

When I was running steppermod, I could get to about 42IPM (motor
sitting on the bench) before the motor would lose a step. Follow
errors were rare. I've since upgraded (?) to freqmod.  I've turned
down CYCLE_TIME to 0.004 and PERIOD to 0.00002.
What neighborhood would I want to be in for cycletime & period ?
but now I get follow errors at >35"/min. (about my comfortable
speed w/ steppermod). The follow error will trip before the
motor skips (within the resolution of my eye, at least) so this
looks a little better, not getting lost.   

What INI parameters are the biggest knobs to tune speed ?

How about FERROR & MIN_FERROR ?  P/I/D/FFxxx ? Still having some
trouble getting stripchart up and running.

To judge lost steps, I have it make a 200" move in one direction and
see if the shaft ends up in the same rotation that it started at.

Thanks,
-Damon
          
[TASK]
CYCLE_TIME = 0.004

[EMCMOT]
EMCMOT = freqmod.o
COMM_WAIT = 0.010
PERIOD = 0.00002

[TRAJ]
CYCLE_TIME = 0.010
DEFAULT_VELOCITY = 0.0167
MAX_VELOCITY = 1
DEFAULT_ACCELERATION = 5.0
MAX_ACCELERATION = 5.0

[AXIS_0]
P=1000
I=0
D=0   
FF0=0
FF1=0
FF2=0
FERROR = 1.000
MIN_FERROR = 0.010