V6 Engine

A very good exercise for learning advance assembly features. I have taken this model with some edits. It consists of: a) Lower Block b) Engine Block c) Upper Block This V6 Engine has one final assembly and two sub assemblies as well of Piston & Rocker Arm. I have used Belt/Pulley which over defines assembly, however, it is working. I have also animated the model, but animation is not good because of slow laptop. Please give me suggestions to enhance my skills.