The "High Pressure" turbo engines have a lower compression

engine to start with and have some other internal differences

to handle the additional stress. Example: HPT engines displace

2.3 liters instead of 2.4 -- the piston bore is smaller so the

cylinder walls are thicker. The extra cylinder wall "metal" is

needed to handle the higher thermal stresses. They also have

stronger pistons and different valves (sodium filled).

So, you can't really bolt-on to have the same engine. But, IPD

sells an ECU upgrade that allows your turbo to build more boost

pressure which means more power. That would be the way to go.

IPD is at www.ipdusa.com. There are other chip tuners, too.