What is an MP5 ?
(or is this just a nickname people have created for the Protege 5)

 

It's just a nickname. Welcome to the boards by the way.

 

And i always thought it was short for Mazda Protege 5

 

Yeah man, welcome to the site. I don't pose often but have been on since I bought my P5 about a year ago. I see you're in the SoCal area. Me too (Carson). Did you just buy one (a P5). If so, what are your plans for mods? First thing I did is tint the windows and putting in some ten inch subs in the back. I just recently put in some interior accent lights . I am planning on a CAI and just putting on a bigger exhaust tip until I can afford a new manifold.
Keep posting!

 

it is

 

can you smell it? ahhhhhh fresh meat, lol
seriously now I think mp5 if I'm not mistaken stands for Mazda Protege 5 door.
oh yeah welcome to da club