A trio of college students discovers street racing becoming deadly when they discover a racer was a serial killer.

Good hook, but add an adjective for the protagonists and create huge death stakes along with a compelling force of antagonism.

Something like:

"A trio of car-savvy college students discover the deadly consequences of street racing when their competitor is an infamous serial killer hellbent on revenge."

I feel like the name of the story is key.

What if this group was "A trio of gear-head college students..." to help with focus? In your story - what is making this deadly? What are the stakes if they lose? Also, would help if you had a big bad rival.

Take care.