BBC swap into Burb??

[lawdog49]

I have located a decent 84 2wd dually, with a low mile 454 and a recently replaced TH400.  How difficult would it be to swap this drivetrain into my 91 4wd Burb that currently has 350/700r4?  Would I have issues with the transfer case bolting to the transmission, length/etc.?  Could I use my TBI and swap in BB injectors after getting a BB TBI intake?

[VileZambonie]

Are you planning on just swapping in the bb or the 400 too? Because if you were going to put in the 400 you'd have to convert it to 4wd and change the output shaft. I would just run the 700R4

[lawdog49]

if the 700 will hold up- i would rather run it.  i guess if it blew i could rebuild it heavy duty or get an aftermarket HD 700.  sounds like swapping in the 400 would be too much trouble- and i do like the overdrive. 

i can get the dually pretty reasonable- and could part out the rest-57K on the truck and engine, the 400 trans recently replaced due to the owner failing to check fluid levels and burned it up.  it is an 84, so not TBI.  would i be able to get an adapter or different intake and run my TBi with bigger injectors?  i think the engine is low enough in mileage and in good shape to make it worth acquiring.  i think the Burb would be so much better with BB torque since it's so heavy.

[VileZambonie]

You can definitely beefcake the 700R4. I put them behind 454's plenty of times as long as it's not too crazy. TBI adapters are available from trasdapt and a few other vendors

[Captkaos]

I agree, swap the BBC only and keep the 700R4, with a BBC in front of it, you will probably want it.
The TBI on a normal 454 has the same Throttle body/injectors as any other motor.  The 454SS was the only one with a bigger TB and injectors.