FULL DYNO RESULTS! LS POWER RULES! 4.8L & 5.3L UPGRADES + BONUS TEST. THE JUNKYARD LS MOTORS are perfect for NA or turbo mods. We show you HOW TO add over 130 hp, by replacing the stock (LR4/LM7) heads, cam and intake. Just how much power can be had with the right components? We show you on a 4.8L AND 5.3L, with a bonus intake test in each!