Is there any way to make the recruitment time less than 2 turns?

Is that possible?

Yes, it is. Go into the export_descr_unit file and change the red number. You have to do it individually for any unit, though.

Spoiler Alert, click show to read: 

type barb peasant briton
dictionary barb_peasant_briton ; Barbarian Peasants
category infantry
class light
voice_type Light_1
soldier barb_peasant, 60, 0, 0.7
attributes sea_faring, hide_improved_forest
formation 1.2, 1.8, 2.4, 2.4, 6, horde
stat_health 1, 0
stat_pri 1, 0, no, 0, 0, melee, simple, piercing, knife, 25 ,1
stat_pri_attr no
stat_sec 0, 0, no, 0, 0, no, no, no, none, 25 ,1
stat_sec_attr no
stat_pri_armour 3, 1, 0, leather
stat_sec_armour 0, 0, flesh
stat_heat 2
stat_ground 2, -2, 3, 2
stat_mental 0, low, untrained
stat_charge_dist 30
stat_fire_delay 0
stat_food 60, 300
stat_cost 1, 150, 100, 20, 30, 150
ownership britons

Note that the above EDU entry is drawn from vanilla RTW. I don't have Sparta installed right now.