Max Torque Big Block

I have to say that although deisel power sounds attractive the reality is nobody puts enough miles on a motorhome to pay off.
The early 6BTs only put out around 400 ft/lbs and at such a low rpm it would require a rear gear change.
Then consider how hard they are on A/T and that pushes the price up even further. Then you have to cool that beast !
For around 5 grand you could build a stroker BB easily... Its the head requirements and cam profile that are in question.
And just how much torque can you get out of a BB that would survive motorhome conditions.