Toddy, Thanks for the compliments! · The Gen V intake has longer runners with an improved shape and entry. It will outperform a ported Gen IV manifold. · Same lift, longer duration and acceleration. · The aluminum flywheel dissipates heat better and does not require as much thermal mass. · Exhaust changes include a single pass wash coat to the cats (for precious metal deposition) and a new resonator (see answer to post #9). · The Gen V head gaskets will work on Gen III & Gen IV and would be a cooling improvement but there also some holes in the head that would need to be added and one that would need to be blocked. · Fuel cut-off will remain at 6400 rpm. · Same basic rear differential with 3.55:1 gears and new stud shafts and half shafts for improved serviceability and function.