4 wheel drive set up good or bad? sb400 700r4 4:11 gears

[Hazieview]

Hey guys I'm looking at buying a suburban and swapping out the engine in it with my sb400. MY sb400 will make around 580lbs of torque at 9.5:1 compression, according to are rough estemations.

So the setup will be:
1985 Chevy Suburban
4x4
8" Lift (all suspension)
38" Tires
sb400 (580lbs of torque)
700r4 (he said it has kevlar clutches)
4:11 gears

Well do you guys think it will be okay?

(not sure what kind of transfer case or torque converter)

Thanks!

[72chevyk10]

with 38" tires I would put in more gear then a 4.11.. 4.56 absolute minimum imo

[b454rat]

if indeed he is making that much torque, he won't need a steeper gear. He will need a better tranny and t-case, like a 4-speed or 400 and a 205 case.

How do you figure your motor is making that much torque??

[Hazieview]

Originally Posted by b454rat

if indeed he is making that much torque, he won't need a steeper gear. He will need a better tranny and t-case, like a 4-speed or 400 and a 205 case.

How do you figure your motor is making that much torque??

Because I built it...? Oh and the guys that work at the machine shop with about 30 years experience who ordered the parts and machined it for me confirmed it.

Kind of off topic here. If you want you can PM me.

I was wondering about the gears too. It has 40" tires on it.

[Mr. 250r]

i have a 91 3/4 burban on 38.5s with the stock tbi 350 and 4.10s and a 4l80e/np241 it does fine except for an occasional bog down but a new motor is coming in so im not worried about bogging anymore

[special-K]

Sounds like it'll work ok. Your gears will be in the mid-lower 3s after your tires,so that'll work fine for street.O/D may be a bit tall. 4.56s would probably be best. The transmission can be built to take it. 700r4/NP208s are pretty common,then came the N241 in '89. There are 4L80E/NP241 combos from '91 3/4 Suburbans and CrewCab 3/4 & 1 tons. You want to get the electronic speedo stuff from the donor,too. I think the same for the 90/91 700r4/N241s.