350 or LS

[Cruck]

350. That is what belongs in that truck. Bolts right in, no computer or sensors. JMO, many others will speak differently.....

It actually came with a 6 cylinder. I inquired about doing that but so many have advised against it. It will have more power than it originally had and is a bit more modern. Not sure why it was frowned on.

Compare milage on vortec suburban vs. ls suburban. Almost identical. Do injected SBC trucks start right up and drive? Yes. Did millions if people count on 350 burbs and Escalades as mom and kid transportion? Yes. SBC is reliable and not horrible on fuel with modern engine management. Buy a 5.7 lt1 roadmaster (lt1) swap in the engine,transmission ecm and engine harness. Cheap fuel injection,good engine management,and it's a bolt in. Or swap in a complete TBI or Vortec drivetrain. Including engine management.If your real goals are just easy,reliable,and decent mpg. If just an occasional driver stick a good carbureated 350 in it and call it a day. The difference in cost will pay for a lot of fuel. And people counted on carbureated 350s for decades,to run business, get to work, cross country on vacations. We still had vehicles we could count on ,before LSs

I read about adding vortec headers to the 350 block and modern fuel injection instead of a carb. How much more fuel efficient would that be?

My 350 was tired and worn out, took it out and had the shop bore it and made a 383 stroker. I love the way carb engines sound at idle. I did think about doing a LS swap, but making a 383 came out way cheaper then doing a LS swap and way easier. But honestly its your truck, do what you want.

This 383 idea sounds good. How much more power would it have? Would the fuel mileage be better?

Budget and capability of the folks doing the work is key. As is how many miles you plan on putting on it.
From my point of view, LS swap for a few reasons.
1 fuel mileage if you plan on alot of miles and going as far as swapping in an OD trans.
2 fun factor. You’ll spend as much or more from my research building a 350 small block that will rev like a stock LS and have the power that a LS with bolt ons will have.
3 being unique. IMO LS swap is still unique and not the norm.

Downsides are it is more complicated as is your situation of what the volunteers are willing to do for you.
I’m in the active contemplation phase of what I ultimately want to do with the powertrain in the 77. Difference being, it has a turn key new 350 under the hood and a fresh rebuilt TH350 that I could drive from here to your house with nothing but a gas card.

All that said, based on your first post, the bigger picture question is what is the truck going to take to get it to where you want it to be?
When you throw out terms like trashed, flooded, rusted out, that sounds like the trifecta of either becoming a parts truck, recycled metal or a complete restoration.
I view “projects” like this in 3 categories.
The “clean, runs, decent shape” only need “100 things”.
The “projects” need “1000 things.”
And a vehicle as you described needs “everything.”
As you’re admittedly new to this without any past frames of reference, this truck sounds like somewhere between the hypothetical 1000 things and everything. Simply because your untrained eyes are able to identify several major issues.
Quick numbers, bought the 77 this past year. Basically as it sits now. The PO resurrected it from 20-30 years of sitting, not flooded, not trashed, not rusted and all in one piece, fired up and limped it home. He is not a mechanic. He gave me $15k in receipts for a truck that has a reman stock engine with new accessories (mostly), stock rebuilt trans and new tires and brakes. Just a quick summary of how costs add up and how they add up to 3x as much when you hire out the work. That $15k includes $0 for body, paint, electrical, interior. It’s nothing but drivetrain and running gear work. And that work was done to a truck that was already in great original shape. IE no surprises or difficulties.
And he never even changed out the original diff fluid! lol
Not trying to dissuade you here, but rather get you to think about the whole process and not just the vroom vroom under the hood. That’s actually the easy part.

That is a lot of work and MONEY!!!

If your truck is in good shape, LS swap is cool now, but 20 years from now it will be a classic truck with the wrong engine.

Great point!!!

Based on your experience level, and the expertise of your crew, a mild 350 build would seem to make the most sense. Lots of info and all kinds of parts available to fit any budget.

The weakest points of the early GM 350 are poor flowing smog-era cylinder heads, low compression, and old design flat tappet cams that don’t mix well with modern oils. All the early 350’s have these limitations, even the mythical Corvette engine that someone's buddy wants to sell you for $***.

My suggestion is to start out with a Vortec 350 (it was the stock engine in mid 90’s and up), or plan to swap heads to use Vortec iron heads or a budget aluminum head. Also plan to use a roller cam (Vortec 350 already has one), or a roller cam conversion. Using that as a basis, it’s easy to build a reliable 325-350 HP 350 with very good street manners.

Someone mentioned to me that I should be using a block stamped 010. Is that a better version on something?

So I am taking a rebuilding class at the local community college. Not the one that is doing the work. I live in the Pacific Northwest and the truck is in the south. I have a running F100 here that is rather tired. It runs and drives but the engine needs a rebuild. My instructor suggested I do a 350 along with my F100 engine. He seems to think even with the cost of shipping the engine I would come out ahead.

The primary use of this truck will be get around when I go home. I head south 2-3 times a year. I am generally there a month or so. No hauling or heavy work in it. Mostly so the folks can stop complaining when I go more than 60 miles in one of their cars. My dad will probably drive it sometimes but not much.

 

[DoubleDingo]

Sixes are reliable. People don't like them because they're not v8. Decide which direction you want to go, block out the bs, and enjoy the rig.

 

[Ricko1966]

It actually came with a 6 cylinder. I inquired about doing that but so many have advised against it. It will have more power than it originally had and is a bit more modern. Not sure why it was frowned on.



I read about adding vortec headers to the 350 block and modern fuel injection instead of a carb. How much more fuel efficient would that be?



This 383 idea sounds good. How much more power would it have? Would the fuel mileage be better?



That is a lot of work and MONEY!!!



Great point!!!



Someone mentioned to me that I should be using a block stamped 010. Is that a better version on something?

So I am taking a rebuilding class at the local community college. Not the one that is doing the work. I live in the Pacific Northwest and the truck is in the south. I have a running F100 here that is rather tired. It runs and drives but the engine needs a rebuild. My instructor suggested I do a 350 along with my F100 engine. He seems to think even with the cost of shipping the engine I would come out ahead.

The primary use of this truck will be get around when I go home. I head south 2-3 times a year. I am generally there a month or so. No hauling or heavy work in it. Mostly so the folks can stop complaining when I go more than 60 miles in one of their cars. My dad will probably drive it sometimes but not much.

If you're not rebuilding your engine,then you do not want to start with an 010 block,thats an old high nickle,flat tappet block.You want to Start with a roller cam block. Adding vortec heads( not headers) without adding Vortec or other port fuel injection, isn't what I'd recommend unless you live somewhere where it never gets cold.Theres other heads that would be more suitable. The 383 will add about 10 percent more HP and Torque than an equally built 350,and about the same decrease in fuel economy,you will feel the difference. Fuel economy difference going EFI won't be huge,but it will atart and run like a modern car,and you need port fuel injectio,not tbi,not carbureator if you vortec heads,unless it never gets driven in the cold. On a budget,again I'd pull a running 350 and 700r4/4l60e,fuel injection,ignition,ecm and engine harness from a 350 vortec or 350 lt1 or 88 up 350 TPI. Very likely get away with rings,bearings,valve job and gaskets. If you need to buy a crank and pistons,anyway,then step up to 383. There is no reason to replace or regrind a good standard/standard crank. If it's out if spec that's when to consider an upgrade replacement. Unless of course the goal of a dependable driver with decent mpg and turns the tires occasionally isn't the real goal, in which case do the LS swap