Weak actuators

I installed 2 two-wire aftermarket actuators into a ford escort. I hooked them up to a viper 350 hv. The actuators came with prewired relays. When the actuators pull themselves shut (thus unlocking the door) they work fine. When they push themselves out (locking the doors) they fail to push out all the way. I have to push the button 3 times to get them to move all the way to the end. It seems as if they are not getting enough power (or are a cheap brand). Is there a way I can increase the power to them like by adding a capaciter to the line? Thanks in advance for any help

Kobaltic

I disconnected the actutors from the doorlocks. They still don't have enough power to push. They are completely clear of everything.

I simply hooked the blue and green wires off of the alarm to the blue and green wire on the relays. the inputs are 16 guage and the ouputs are 12.

ALSO, Make sure your acuators are not binding on the mount or door, like against an edge. The plungers should be able to move freely.  Also be sure to give the plungers approx. 1/4 inch slack in the down position to account for rod and lock movement.