mechanical question(non-srt10)

[savageR]

I have a 77 chevy blazer 4x4 that I am fixing up for my son to drive when he turns 16. Is still a couple years out till he will be old enough. I have already got all the body work done, and a new paint job. I am now working on the interior and drivetrain. I want the truck to be reliable/bulletproof for him. It doesn't have to make a ton of power but just be sufficient for what it is. It currently has the original 400(6.6L)/350 auto combo, with the np203 transfer case. Is the stock set up worth putting money into? Or should I swap it out for something else? I don't see alot of aftermarket stuff for the 400.
Thanks

 

[eddie102870]

id say a 283 with a 2 barrell

 

[Texas Yellow Fever]

99.9% of aftermarket stuff for 350s will also work on the 400. I THINK the only difference (other than the obvious) is that the 400 is externally balanced (IE different harmonic balancer that all other small blocks) and there are steam holes from the block to the heads which supposedly have a tendency to cause blown head gaskets (although I don't really believe that). Depending on what your intentions are the 400 is a perfectly good choice, you can put an aftermarket fuel injection system on it to improve the MPG. Or step up to a crate engine (350/383 etc) from GM and drop it in. The mounts etc are the same as any other small block so doing a swap is a snap...been there, done that...got the T-shirt.

 

[FastRam]

I have a 77 chevy blazer 4x4 that I am fixing up for my son to drive when he turns 16. Is still a couple years out till he will be old enough. I have already got all the body work done, and a new paint job. I am now working on the interior and drivetrain. I want the truck to be reliable/bulletproof for him. It doesn't have to make a ton of power but just be sufficient for what it is. It currently has the original 400(6.6L)/350 auto combo, with the np203 transfer case. Is the stock set up worth putting money into? Or should I swap it out for something else? I don't see alot of aftermarket stuff for the 400.
Thanks

Do you want to alter the suspension, larger wheels/tires? The TH350 is a decent trans and you should be able to find plenty of aftermarket stuff to harden it. The NP203 xfr case is also decent (chain drive OK). Not sure what upgrades can be done to it but I have seen others double up these with a NP205/Atlas gear reduction units. Engine worth anything? Maybe. But how does it run now? Granted you'll find a gizzilion parts for a 350ci from many sources. Summit/Jegs offers a decent selection for the 6.6L. I say if the 400 isn't broke, don't fool with it. You should be able to find the basic upgrades for it (headers/intake/carb/distirbutor/cam/wires/coil, etc.)

Also, if you plan to do any suspension and tire/wheel upgrades, becareful with your axle assemblies. Not sure what you have. But if you have a 10 bolt rear, the biggest tire/wheel combo, without detonating the rear is a 35 x 12.5incher with a 10"D wheel. Most likely you have a 10 bolt front. The outer axle stubs on these are really weak and prone to failure if worked too hard with oversized tire/wheel combos. If you plan on lifting the vehicle, depending on how high you go, plan on drivesahft work to eliminate any driveline vibrations. Another weak spot is the frame area where the steering box attaches. It is prone to shearing and failure if too large a tire is used in the rough stuff. Backing plates to strenthen the frame/box mount are available from several suppliers or can be fabbed up.

Good luck with it.

 

[includemeout]

I have a 77 chevy blazer 4x4 that I am fixing up for my son to drive when he turns 16. Is still a couple years out till he will be old enough. I have already got all the body work done, and a new paint job. I am now working on the interior and drivetrain. I want the truck to be reliable/bulletproof for him. It doesn't have to make a ton of power but just be sufficient for what it is. It currently has the original 400(6.6L)/350 auto combo, with the np203 transfer case. Is the stock set up worth putting money into? Or should I swap it out for something else? I don't see alot of aftermarket stuff for the 400.
Thanks

The 400 is a good engine ( basically a bored and stroked 350) the heads are the same except for some small steam pocket holes in the heads( other heads can be drilled using the head gaskets for templates ( if you need to)
The damper and flex plate has a counter weight (unique to to the 400)

I assume you are in a smog area so changing the engine may require the smog system from another engine would have to be used.

After market parts (headers , manifolds and accessories are the same as the 350). just check with the supplier. If you rebuild the engine, I would suggest
a lower compression piston set so you can run regular gas all the time and new seats and valves for the new fuel formulas.

Gas mileage can be helped by installing Warn lock out hubs on the front axel

The tranny is good, but, a turbo 400 is much better, but the turbo 350 can be rebuilt to hold up just fine.

There are bearing kits to put a 350 crankshaft in that block (makes a 366cu in) many like this set up as it eliminates the need for the 400 damper and flex plate.

Remember the first vehicle usually gets trashed so I wouldn't get to carried away. Just my .02 cents
Oh, try Peterson Publications for the Chevy parts and building book they sell as it has every combination of parts that can be used in the Chevy engines along with many pr oven mods.

 

[FATJACK]

The 400 engine is great, very high torque for a small block. Perfect for a 4x4 application.