Engine turns over and over and over and over... doesnt start....

[BaLListic]

ok well we put in an engine today... basically its a 100% stock 87 5.0... the car turns over fine and sorta acts like it wants to fire and never really does.... could this be bad gas from sitting (2.5-3 years) or is my timing out... well anyway we drained the gas and put new in and now we just need to drain the lines... but anyway we are getting spark and fuel so there should be fire..... and the timing has been checked and re checked... and we arent getting a mis fire.. so im thinking it was just the old gas?? should i try some starter fluid to see if it will get the thing off its ass or what???