Camaro, but I'm obviously biased. LS swap is the way to go. 5.3s can be had from less than $500 from intake to oil pan with a harness. Expect nickle and diming though. I'm currently in the process of putting a LQ9 6.0 in the Camaro in my sig. I'd just do the swap first, and work with the turbo(s) later. Keep the stock exhaust manifolds. Alot of guys are cleaning them up and welding v-band flanges on them for their turbo setups. Thats why I'm keeping mine.