Audi 80 Question??

Just a couple of questions.
1. What is the difference between a B3 and a B4
2. Also what is the my powerful engine that can be fitted into a 1989 Audi 80.
Many Thanks
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.