EMC step rate configuration

I'm finishing up my grizzly/EMC conversion... How cool it feels when
you
jog your first axis!

Now I'm thinking I've made a big design mistake: I used some surplus
motors
with pretty high resolution encoders, which I'm driving with the
wonderful gecko G320's, and are coupled to 10 TPI acme screws
with 2:1 reductions. Working through the math, I end up with
MANY MANY (Way too many!) steps per inch. Way more than I
can use... (like 100000+ steps per inch)

Configuring EMC, I'm finding the relationship between MAX_VELOCITY
and INPUT_SCALE to limit my max speed. I'm using the default
PERIOD, etc setting in EMC on a K6-266. Obviously, if I set
the velocity too high, EMC hangs during startup, since I've
set things faster than the pulses could be output.

Short of changing encoders/motors (which I've done temporarily on
my Z axis, just to get a tolerable speed for tool changes), what are
my options? I don't care about speed while I'm machining much (it's
not a production type machine for obvious reasons), but jogging, etc
is slow.

Some things I've thought of:
1) Adjusting the EMC parameters to maximize what I can do. I'd like
advice, potential period/cycle values, etc. I've been sticking
to MAXVEL * INPUT_SCALE = 5000, but need to figure out what
setting is forcing the 5000 (obviously I'm limited by what
the intel hardware can do, and the executive speed, plus
non-realtime overhead).
2) Modify the pulse generation routine to "double pulse" and divide the
input
scale by two. To get a usable pulse width, I'll be increasing the
execution time of the critical section, so I may run into hard
realtime
deadline problems here.
3) Add simple external circutry to "pulse multiply" and divide the
input scale.
I suppose I could program a pic or use some logic/timers to do this,
but
I've got everything wired up so nicely...
4) Others?

Thanks to everyone who has helped me out tremedously in this project...
When
I finish things up, get my limit switches on, etc I'll take pictures and
describe my Z implementation, etc. I end up working on it on the
weekends,
figuring out sunday what other parts I'll need, placing the McMaster
order
sunday night... Parts arrive friday.. The cycle continues ;)

The bi-polar "deathstar" power supply already had the 0V terminal
isolated, and
works great... (other than the lights dimming!).

Thanks again
murph