The V4 is a four stroke V4 engine, is like a half V8 :)
Here you have some pictures on the engine:
[ame="http://www.google.se/search?q=saab+v4+engine&bav=on.2,or.r_qf.&bvm=bv.52109249,d.bGE,pv.xjs.s.en_US.8f7UbUMizFk.O&biw=910&bih=428&dpr=1&um=1&ie=UTF-8&hl=sv&tbm=isch&source=og&sa=N&tab=wi&ei=H90xUuLNJebw4QSYtIHgBQ#hl=sv&q=saab+v4+engine&tbm=isch&um=1"]saab v4 engine - Sök på Google[/ame]