Hey guys, I am going to be buying a 07 nnbs vortec max as soon as my duramax sells. It has the l76 6.0 in it with 159k miles. From my research the dod/afm lifters are junk and are probably close to going out. So I figured I should delete that and do some mods to get some lost power from my duramax 600whp dmax lol.

Heres what I have planned so far. I have a few questions on some things and figured this would be the place to go.
-black bear tune 91 octane
-Texas speed long tubes and y pipe (is non catted very raspy and loud?)
-Texas speed stage 3 vvt cam

What heads does the l76 have? I figured if I have to take the heads off maybe it's worth swapping for 243? or if the heads are good, can I mill them down to bump compression up? The truck l76 has pretty low compression and I plan on running 91 anyways.

When looking at cams Texas offers a low lift and a high lift version. What's the difference between them?

 

Has LS3 heads, I'd keep em.

Difference between high lift and low is the lift, obviously, .05" in this case. I think the hp is like 17 different?

I find that a non catted Y can be very raspy, especially on cold starts. Care must be taken when selecting the muffler(s)

I have lifters if you need a set

 

I suggest not going with blackbear. Sometimes I question if that guy even knows what the heck he is doing. Trying to get them to do a custom VVT cam will just be testing your patience with all the waiting you are going to have to do with that stupid email tuning.