I'm just kinda shootin this one out here, but.........Why in the world would you wanna lift an ls1 6 or more inches?
We're talking about one or the best race engines you could work with.
When is the last time you seen a corvette lifted off the ground on some big knobby tires?
You don't. But you do see them close to the ground on some nice slicks smokin up the track.
Personally, if you were going for an engine with good performance and torque, I would go with the 6.0 LQ4 and a 4L80E swap. With a nelson tune and a good locker that baby would pull you right up a mountain side.
Leave the LS1 for racing. Plus you'll save some money by going with the LQ4.