OH SNAP! Effin badass cars mayne!!!!

The LQ9 had stronger piston rods and bolts, along with flat top pistons, which result in the higher CR numbers. The LQ9 can easily handle 8-10 psi. But if you are only going 8-10 psi, why go twins?

The 5.3L would respond well to FI too. You could save the $$$ on the 6.0L swap and use it for modding the 5.3L and get a nice LVL 5 tranny to back it up--cause the stock 4L60e is not going to like 8-10 psi at all. But with either motor, I would definitely go with all supporting bolt on mods with a nice turbo cam to get the best output. As for the intake...I would keep the stock truck intake--cause if you go the LS1/LS6 route, you will need to do the LS1 style accessory brackets to make it all work with the shorter intake.