This was a fun part. I prefer using 3dsMax for hard surface modeling because I find certain key tools more useful in speeding up my workflow. For example, the Modifier Stack, Edge Loop, Edge Constraints, Align and Array tools in 3dsMax are easier to work with in my opinion. I am a long time Maya user and also use it every day at work so I am definitely making a fair comparison. Don't get me wrong there are things about Maya I wish Max had as well, especially like it's quick snapping functions using the X,C,V keys. Overall though Max got the job done a bit quicker for me in this particular situation.
I also find instancing in 3dsMax more practical which is key for models like this engine. I have a bunch of instanced parts off to the side while the other instance is already positioned at an odd angle making editing those individual parts easier if needed.
There were a lot of fun shapes to model and all started with a basic rectangle or cyclinder. I kept everything quads which sped up the sub-d modeling using edge loop.
Here are some shots of my progress so far.
