Of course the pre-trib rapture is biblical. There’s all kinds of proof for a pre-trib rapture.
http://www.raptureforums.com/Rapture/index.cfm
“Although the pretribulation rapture theory is very popular today, given arguments that are offered in support of this doctrine we must declare Pretribulationalism to be contrary to the clear teachings of Scripture. Simply put, there is not one shred of evidence that can be found in the Bible to support the pretribulation rapture.”