Newbie building router ?

Well here is the setup:-

Alzanti pvp134 drivers.
Superior Electic 110oz 5.1v stepper motors
4mm pitch leadscrews with bronze anti backlash nuts
all running on linear ball bearings and hardened shafting
machine approx 1250mm * 850mm

Question
I will be driving the leadscrews through toothed belts
and pulleys to the leadscrews.The motors are only capable of approx 3
r.p.m .
Would i get away with gearing 1:2 on the pulleys so as to give me more
rapid traverse (ie 1440mm/min) or would this reduce the torque below
what would be needed to drive the machine?.I know these motors are
not ideal but they are cheap (£15.00 ea).
any advice would be greatly appreciated as i can not afford to get
this wrong

thanx in advance
mark