77 Suburban build for AK

[Carl S.]

Hey all, new here, looking for info on building up my 77 C20 Suburban for surviving better in AK. It has a carbureted 5.7 with a thrown rod, np205 transfer case and a 4 speed manual with granny low. I'm going to put in a carbureted 454 with an engine block heater, swap the gearing in my diffs, and install a 12" lift. My main concerns is in regards to the engine swap.
1) Will some parts from the 350 be transferable to the 454? I'd want to move the power steering pump, alternator and mechanical fuel pump.
2) Any tips for helping the engine in the cold? Up until blowing a hole in the side of the block the 5.7 has started right up without an engine block heater, even when it's -50°f in the mornings. I want the same reliability in the new motor I'm putting in.
3) Will I need to upgrade my radiator from the one for the 350, and if so will I need or want cooling fans on radiator, the warmest it gets here is sometimes into the 90's, but usually only lower 80's.
4) I plan on mounting the engine and transmission lower down in the frame to help with driveline angles and to help lower my center of gravity, all of which are effected by the lift install. Have any of you done this, and should I use motor plates to mount it lower in the frame or custom brackets and do the rubber mounts? I realize that motor plates will stiffen everything up, how much will that effect driving it on the street?

Any advise or info you may have for an off road beater in Alaska is greatly appreciated.

 

[74 Shortbed]

Welcome to the site.

 

[1973c10]

Hey all, new here, looking for info on building up my 77 C20 Suburban for surviving better in AK. It has a carbureted 5.7 with a thrown rod, np205 transfer case and a 4 speed manual with granny low. I'm going to put in a carbureted 454 with an engine block heater, swap the gearing in my diffs, and install a 12" lift. My main concerns is in regards to the engine swap.
1) Will some parts from the 350 be transferable to the 454? I'd want to move the power steering pump, alternator and mechanical fuel pump.
2) Any tips for helping the engine in the cold? Up until blowing a hole in the side of the block the 5.7 has started right up without an engine block heater, even when it's -50°f in the mornings. I want the same reliability in the new motor I'm putting in.
3) Will I need to upgrade my radiator from the one for the 350, and if so will I need or want cooling fans on radiator, the warmest it gets here is sometimes into the 90's, but usually only lower 80's.
4) I plan on mounting the engine and transmission lower down in the frame to help with driveline angles and to help lower my center of gravity, all of which are effected by the lift install. Have any of you done this, and should I use motor plates to mount it lower in the frame or custom brackets and do the rubber mounts? I realize that motor plates will stiffen everything up, how much will that effect driving it on the street?

Any advise or info you may have for an off road beater in Alaska is greatly appreciated.

Welcome aboard

When I did me big block swap
I used the same power steering pump and alternator,
the alternator brackets are different
the fuel pumps are different
I used the same motor mounts
The flywheels are different one is internally balanced ( 350)
and one is externally balanced ( 454 )
The Distributor is the same
as for the radiator I put in a 4 core radiator with a stock fan
and fan shroud
I am sure I am missing some other thing but it a start

 

[Carl S.]

The 454 I have comes with a distributor and flywheel, so I don't have to worry about that aspect. I can get the mounts to reuse the alternator and power steering pump. Do I really need a fan shroud? I don't have one now on my 5.7...

Any input on how to mount the motor lower in the frame?

 

[bucket]

I don't think lowering the driveline will help much at all with center of gravity. Most of your weight will still be up high. And you would have to lower it a lot (like 6 inches) to solve the driveline troubles and run stockish shafts. And then there's the steering to deal with too. If you want that much lift, no matter what, you will have to spend money dealing with the 'big lift' issues.

 

[GTME94]

I was just looking at pictures of my engine installed without the front clip on the truck. There's not that much room between the bottom of the exhaust manifold runners and the top of the frame rails. You might get 3 or so inches lower and then the manifolds would hit the top of the frame rails.

 

[stlbob]

I run a carbed 454 and you will need that shroud it really helps cooling with these brutes.I use a simple magnetic heater that i attach to the oil pan,really helps the cold starts. What type of carb will you be running.? As others have said the whole lowering the engine and trans and Tc for a better driveline angle is just a can of whop ass you dont want to open.

 

[RThiel]

For Alaska I would double down on things as a mistake there can be deadly. Run a large radiator and fan with a winter front on it. There may be times when you're pushing the engine hard through snow, but not moving very fast. Put two block heaters in, two batteries, and make sure your air filter is protected from sucking in snow.