the 4.8 is the same bore as the 5.3, shorter stroke right? So what do you get when you combine a 6.0 block and a 4.8 crank? what CI does that equal, does anyone use this for higher RPM's?

 

I've heard of some using a 4.8 crank in a 6.0 for a high revving engine. The 4.8 and 5.3 have the same bore but different strokes. All of what MJHoward said is right on; he knows his stuff.

 

Exactly right, bore is same but stroke is different. 4.8L is about 292ci while the 5.3L is about 325ci.
Like Stroker said some folks were using 4.8L cranks and rods on the 5.7L or 6.0L motors for a rev happy assembly.