switch out 350 for 454

i have been working on a my 1992 chevy silverado 4x4  for about 3 years now doing little odds and ends to make it an aggressive four wheeling truck but also a daily driver. the question is that i have not really messed with the engine yet because i am trying to get as much out of it for as cheap as i can. but my grandfater has a 87 chevy suburban that he is looking to get rid of and the engine just a needs a little work and i was wondering how hard it would be for me to switch out the 350 5.7 for that 454 big block or would it even be worth the time and trouble.

if any body as tried this or has any suggestions on if the tranny would have to go also please help.

thanks

It is basically a bolt in. Install a bigger radiator and I would swap tranny too because I would not put a big block on a 700R4 or 4L60 even though some do. Also, you might consider keeping small block and warming it up a bit and installing some deeper gear for big rubber (4.56 to 5.13 depending on tire size) and you will be surprized as to the power you can get out of it as the year 454 is really pretty mild and will not rev up much with any amount of power.  

It depends on were you live and the smog requirement. As far as I know you cant instal an older engine into a newer vehicle without running into legality problems.

Good point on the emmisions but it would not be hard to fix because HD emmision have changed little if at all durring that time frame so you should be able to bring 454 into compliance.  

yeah the engine is out of a 86 or 87 chevy r20 suburban that dosen't have a lot of miles on it and for the emmissions i live in the great state of texas. but the engine is a big block and i think i would have plenty of room. but as a transmission goes i would use the one that is in the suburban but i dont know that it would work do to it  being a 2 wheel drive and my truck being 4 wheel. but if you have any more suggestions i would be glad to hear them or if you know of any companys that sell parts that would help the switch i would appericiate it.

thanks

you would also need the wiring harnes from the donor vehicle(454)
you will need the hd fuel pump from the 454 donor
also the computer
do both of the trucks have hydrolic breaks ?
keep all the sensors on the harnes,they need to go with the 454 harnes.
your engine mounts are the same, as for your trans to  

O crap... just seen the dates on this post LIKE THREE YEARS AGO  

454, a 700r4 is a good tranny to have aswell I think you have the newer version too, atleast a shift kit and tranny cooler after that if it breaks just build it up it will handle the power, you will probably get 2-3 mpg. increase with the 454 over the 350