Project tempo nightmare{logic pro}

[Richierich]

I'm supposed to remix a song with no tempo info.
I've tried setting the tempo from the session's audio drum loop track. I trimmed the loop to 4 bars and set the song tempo to region length. After a few bars the tempo loses synch.
The drum loop was consolidated in protools, and sounds like poop. The song begins with an ad libbed intro{no tempo}, than the loop comes in and plays until the end of the song. I don't have the original file, just a consolidated region with 16 bars of silence at the beginning. Any ideas how I can get this to work? Please?

[Richierich]

I got it. Simply put a bpm insert on the drum loop track. Timed the project tempo to the reading and lined up a new drum loop to the old drum loops first transient.
Thanks to SFninja's youtube tutorial.