yeah expensive compared to z6 with forged internals. Lets put it this way. If you are looking for power go with the z6 forged internals, thicker head gasket to lower compression (i think it is thicker), ARP head studs, tune it, throw a t3 turbo on that bitch boost it at 15 psi or higher and you will have a car putting out a lot of power right there and there are still mods you can do. But if you are building a show car swap the b-series, turbo it, do a wire tuck paint your valve cover, tune it and run like 5 psi. I wouldn't wanna run too high of boost on any stock motor. Unless you got money to burn.