we did a compression test on my non running gsr engine and got horrible compression numbers, is it possible that the motor may not be blown?

like can anything else cause the motor to have no compression? (like inside the head - valve timin ? maybe be off by 180?)

 

could be a blown head gasket
holes in pistons
messed up valves

 

If it sounds to smooth when you crank it your cams could be off and you're not building compression.

 

the timing could be off, or valves