Assuming we could get somebody to build a different camshaft for the Durmax what do you think it would need? What do you think it would do? What are the specs on the factory camshaft?

Seems to me the camshft is highly overlooked. You can try and cram all the air in want but once those little doors are shut, ain't no more air goin in.

I don't know what the stock cam specs are but I would bet that they are fairly significant. Since drivability, idle quality, and emissions will not be effected with a large profile due to no vacuum requirement and since only air is going in nothing should be effected.
I would guess duration @0.050" lift to be around 240-250 assuming our engines have rollers in them. This is only a guess. I never looked at diesel camshafts much but have played with gas cams ALOT!! 240deg is significant for a street gas engine (non-roller).
It is true that with more duration/lift we could cram more air into the engine given a certain airflow. Typically, boost goes down when you increase cam spec because more air is getting into the engine. However, since the air is not the limiting factor given the larger turbo's available changing cams is probably not the best way to go. I would like to see the effect of a larger cam with a stock turbo and a heavily fueled engine:rolleyes:
One other draw back to high lift/long duration camshafts is valvetrain durability. If you want to hold the valves open longer you need to open them sooner and faster and maybe more. This creates the need for strong springs. Hence more energy required to open them and longevity will suffer. The only saving grace with a radical cam is the low rpm's we run at.

Well thats enough :blahblah: for now.

Just guessing but I bet the lift is already perfect. These new heads and new engineers do a pretty good job of building a cam with optimized lift.

I would think duration would be the main spec to change.

Less boost more power :eek: foreign concept around here.

4 valves per cylinder
turbo
=
little cam timing restriction