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There has been some talk about this in the LHS/Intrepid groups.

The basic theory (this has not yet been done so its still theory) goes that you can take some 3.8 parts and throw them in your 3.3 and get more power. This is true, since they use the same block alot will bolt right in.

What exactly could work?

The 3.8 is a bored-out, stroked-out 3.3. That said... lets note the differences and what is not different.

Starting with the intake: The 3.3 and 3.8 use the same intake manifolds and heads for any given year. Thus a 1992 3.3 and 3.8 use the same heads and intake manifolds, the 2005 3.3 and 3.8 use the same heads and intake manifold... the difference thus is from year to year for these parts.

Since the 3.3 and 3.8 use the same heads, to stroke out the combustion chamber, the pistons and/or connecting rods and/or crank must be different. So... if you use the 3.8L crank and rods in a 3.3, you might be able to get a 3.5L V6 (not the same as THE 3.5L from the LHS- but rather a 3.3 making 3.5L of displacement). It is believed, however, that the connecting rods are identical. Thus we now have the crank and pistons to contend with. The piston measurements, from top of the pistons to the pin is (according to the intrepid boards): 42mm for the 3.3, 36mm for the 3.8. So part of the difference in stroke is made up by the piston & piston pin assemblies.

We know that: The 3.3 crank uses a 3.19" stroke, while the 3.8 uss a 3.42" stroke. Additionally, the 3.8 uses shorter connecting rods (since there is a longer stroke with the same deck height).

When it comes to camshafts, the 3.3 has used 3 or 4 types- the 1990-1993 type (whats used in the Dynasty OEM) which works with the "shrouded" heads... after 1993 the heads are not shrouded. Thus one might want to consider using newer heads in their Dynasty to use newer cams. The 1994 cam increases low end torque by a noticeable amount, increasing acceleration by 2 to 3%. However considering how similar all these varrius cams are, it might be easier to just pay a machine shop or cam manufactorer to custom grind a cam to your needs. The 3.8 has only used 2 or 3 cam types, but they are identical to the 3.3 cams and are interchangiable.

So, all this said- the best 3.8 parts to use in a 3.3 (pending tests to make sure it would work) would be the crank, connecting rods. After that, a newer style (say 1997) heads & cam from either a 3.3 or 3.8 would be ideal for increasing low end torque and acceleration.