3.73 stock gears in the rear....and the truck is also 4x4

 

3.73's aren't terrible. I'd do the converter first, then if that's not enough go for some 4.10's or 4.56's...

 

You've got a pretty good case of over-camming there, without the correct supporting mods it's gonna be a turd below 3500rpms. you REALLY need a 3k converter and no taller than a 28" tire. look into long-tube headers to help you pick up some low-end and having the cam advanced 4º will help things out in the lower rpm's too

 

I Agree.
I am running a similar cam in my 5.3L. Advanced 4 deg helped but i am still lacking in the low end with these 32" tires!
I think Headers would do it for me but alas, I am in Kalistan and their not quite legal.

 

4x4...he'd have to re-gear both diffs, right?

 

Hay , I just weighed mine , not more than an hour ago. The 245/70/17 weigh 67lbs. without lugnuts and caps, chrome oem wheels,.I have some replica chrome SS wheels , 285/50/20s and they weigh 76lbs..The reason that I weighed them is that the shocks on my truck don't seem to handle the stock ones very well and the added 10lbs. seems to put even more hurt on them.

 

Only if he ever wanted to engage 4wd

 

you still have to regear even if not engaged. both diffs have to spin at the same time

 

$$$CH-CHING$$$

 

you know exactly what the cam does....terrible before 3500k after that though...wow....advancing the cam 4 degrees, how is that done??? and i have the long tubes...