Yes an LS-7 crate engine will have high compression and a big cam, the earliest ones were essentially the same as the engine in LS-7 Chevelles, as the years went by there were changes to use the latest replacement parts but they were still pretty much functionally the same, forged high dome high compression pistons, solid lifter high lift long duration camshaft that was essentially the 2nd design L-88 cam, big bolt rods with the boron rod bolts and the nitrided forged steel crank, pretty much the pinnacle of Chevrolet crate engines until the advent of the 502 crate.as Dakota tom said they did have some quality control issues for a while John Lingenfelter said in print back in the 80's that the LS-7 crate was a great engine provided you took it apart and cleaned everything and reassembled it with proper torques, he said you could clean it and literally get a handful of shavings out of it. As the others have recommended it is probably not the ideal engine for your intended application, a Gen 5 or 6 flattop piston shortblock with large oval port closed chamber Gen5 366/427T heads or Gen6 L29 Vortec heads they both have an ~100 cc chamber and will bump the CR up to 9-9.5 such an engine will make plenty of power for a truck with the right cam and induction, thats essentially what is in my 64 K20 now and it has more power than that old chassis can stand.
