Getting a good solid 300 hp is quite doable with torque in the 450 ft lb range

With a good cooling system (Fan/radiator etc.) I think the 325 hp range is a goal that can be achieved.

Biggest issue is getting rid of the heat.

Unlike the direct injected engines (Cummins and Dmax) the 6.5 burns its fuel in the pre cup in the heads which really limits the ability of heat rejection.

With a high flow water pump and a good radiator and a very responsive fan/clutch assembly the heat issue can be dealt with.


Setting the bar at 325 hp is a very doable goal.

A 4911 mechanical pump can get the job done.


Another issue to contend with is getting a turbo that flows freely and does not hold in a lot of heat.

The 6.5 also does not do real well over the long haul with boost pressures over 15lb

This is do to the limited number of head bolts and the head gasket type.

Keeping the boost pressure at 15 pounds with a charge air cooler in the system the 325 hp level is attainable with fairly good longevity.

Looking at 18:1 static compression ratio is a very good place to start.

Running these engines at high boost with the 20:1 or more comp ratio takes things into the "sketchy zone" as far as long life goes.


325 hp and 500 pounds is likely very doable and still keep the thing alive over the long haul