For cheats in this game, use the DOS utility DEBUG.  
First backup your game, then type the following from 
the DOS prompt:

ren apb.exe cheater.cht
debug cheater.cht
Then for infinite lives, type:
e 14fe 90 90 90 90
For stop timer, type:
e 725 90 90 90 90 90
For infinite health, type:
e 72a 90 90 90 90 90
Then type:
w
q

Then rename CHEATER.CHT back to its previous name.