I would get some 3.90s if I were to ever change gears.

 

I think around 24-2500 RPM at 75 MPH

 

where you getting the gearing done?... i had mine done at Tucson Differential off of 29th... the eaton and gears were like 1100 after labor...

 

Okay, so I'm NOT going to go with 3.90's, to me the extra $ would be best spent elsewhere. Here's some info that should spark some interest. From richmondgear.com:
at 75mph and 285/50/20 (31.22") tire
3.73's 2108rpm
4.10's 2317rpm
4.56's 2577rpm

and for around town at 45mph
3.73's 1265rpm
4.10's 1390rpm
4.56's 1546rpm
Now I'm begining to lean toward the 4.56's. Here's some more food for thought: with 4.56's and 6400rpm shift setting
1-2shift @42.6mph
2-3shift @76.7mph
3-4shift @130mph

My truck will never see 130mph, so I think this gear would definatley be 1/4mi compatible and street friendly. My friend and I compared it to his car (96 Z28) and with his 25.6" tire and 4L60E it's like him having 3.73's. F-body guys have those ALL the time on the street. I'm still looking for your input and suggestions though.

 

Western Differential. Mark the owner is hooking me up with a sweet deal on a posi unit. He does really good work, and he made the awesome custom 9" for my Camaro. I've talked to Tucson Diff. in the past, he's done some of my dad's trucks for his fleet. He tends to set them up a little tight....so I've heard....I've also heard the opposite so who knows?

 

2500RPMs more or less.

 

well if you ever see nitrous or smaller diameter slicks.. i think you'll run out of gear with 4.56s

 

At 75mph with 4.56's and 31.22" tire the rpms would be about 2500, compared to 3.73's and 2100. 4.10's would put you at 2300rpm. That's what was meant.

In third gear with 4.56's at 6400rpm I would be at about 130mph. My truck will NEVER see that, especially in the 1/4mi! Even with a 28" slick in 3rd gear at 6400rpm I would be at 117mph. I'll never see that in the 1/4 with this engine, even with nitrous.

I just think that 4.56's might provide me with the torque multiplication I need to be on par with a 5.3L and 3.73's. It will at least be fun to drive around in town.

 

if i read correctly you have a converter. 4.56s and stall converter.. + n2o = <-- your tires

 

I see about 2500rpms in my truck at that speed, that's what was meant