High Performance Diesel.

Speaking in generic terms, since there are so many fuel systems, injection systems and all around differently designed engines out there, here is a basic explanation.

Step 1. Get gages! Hook them up before you do any modification.  This way you have a baseline of what the engine should see under ideal conditions.  A fuel psi gage between the lift pump and the injection pump will let you know if the injection pump is being starved of fuel.  This is also a "must" since the injection pump is lubricated and cooled by the diesel fuel.  If the injection pump goes bad, you're looking at some big bucks to replace it.  An EGT (exhaust gas temperature) gage with the pyrometer mounted between the turbo and exhaust manifold will let you know how hot it is in the combustion chamber.  Too hot of a temperature could mean burnt exhaust vales, guides and seats,  burnt seals on the turbo, and even melted piston!  A boost gage will let you know how much air is being forced into the combustion chamber.  More boost will also cool the EGT's down some. 

More Fuel.  The easiest way to increase diesel power is to increase the fuel in the combustion process.  You can either increase the amount of fuel being injected by changing injectors, or increase the amount of pressure the injection pump is providing to the injectors by changing injector pumps.  Another way is to increase the duration of the injector spray.  This is done through the injection pump itself also.  On the newer electronic engines with ECM's that tell the injector pump what to do, you can interrupt the signal between the ECM and the injector pump and reprogram it to make the injector pump inject sooner (advance fuel timing) and inject more fuel (fuel injection duration).  More fuel will generate more power and more power means more heat.

More Air.  If you add more fuel you must add more air into the combustion process.  You can get a free flowing air cleaner to do the trick.  If you have went to the extreme side of "more fuel", then you need to look at getting more air by getting a bigger turbo.

Bigger exhaust.  All this extra heat must be dealt with now.  If you make an engine breath better, you have to make it exhale better also.  A free flowing exhaust will be needed.  This could mean getting rid of the muffler, or adding an extra inch or two to the diameter of the exhaust pipe from turbo to tailpipe.  This will also lower your EGT's. 

As you can see, with out going into great detail, it is very easy to get more power from a diesel.  Just remember, to get more power, you need more fuel.  If you get more fuel, you must have more air.  If you have more air coming in, you have to make more air leave.

E-Mail me any questions you might have.