New motor... from 250 to 350

[justhorns]

I ran across a good built 350 for $1000. My truck is a base 6 cylinder 1981 that runs good, on an original 6 cylinder with 80,000 miles on it. I'm the second owner and bought from a friend who was the first. So, if I get the motor what upgrades must be done...

Tires, wheels, rear locker in my 12 bolt rear, new front brakes (already disc) and a power booster to get power assist.
should I bolt it to my saginaw 3 speed (on the floor now) or upgrade to a 4 or 5 speed?

A new dual exhaust is mandatory ( I wonder if I need cats?)

What does everybody think. My budget is limited so the project will be phased..

 

[justhorns]

Oh, and maybe fix the outside of the bed on passenger side

 

[WebMonkey]

nothing wrong with a good 350 transplant but the way you describe your truck, i'd leave the six in it.

i'd spend my project money on the other things you listed.

a locker in the rear of a 2wd might help out in a slick spot.
cosmetics are always nice.
i drove an f100 without assisted brakes so i can see the benefit of powered assist but might be low on the list.

sorry i couldn't be much help but if you're not towing/hauling up a hill, i'd save an engine transplant for last.

good luck
'monkey

 

[Grit dog]

Totally depends what you do with the truck or plan on doing with the truck.
None of the other stuff you mentioned is necessary for an engine swap except figuring out how to pass Denver emissions testing unless you already have it registered in a no emissions testing county.

A small block swap into that truck is about the most straightforward swap of any vehicle. At a minimum, if you have a complete running engine and a base model truck with no AC, power brakes or cruise, it’s a drop in as far as I know and you’d need to figure out radiator hoses, fan shroud, hooking up the throttle and an exhaust.
Do that first to have a running driving truck. The rest of the mods you mention are largely or completely independent of what engine is in it.

Considering or assuming what you are saying about budget, if it’s just a daily driver, you’re money ahead leaving it is is. Cost $0.
If doing a swap, the $1000 engine will be about half the total cost, before any of the “other” upgrades. Unless you’re very saavy in parts sourcing. Just a new exhaust is $300-600 bare minimum depending whether you go dual or single and whether the engine has manifolds or headers already.

 

[fast 99]

Before starting make sure a motor swap is legal in your state. Back when Washington had emissions, motor swaps were almost a no go. Could be done, but every emissions item for the year and motor had to be on it and pass a tailpipe test.

 

[justhorns]

well, the motor was going to need a full rebuild too, so I backed out. Thanks for the help. Perhaps someone has a good non- integral 6 cylinder head for the present 250-6

 

[Grit dog]

well, the motor was going to need a full rebuild too, so I backed out. Thanks for the help. Perhaps someone has a good non- integral 6 cylinder head for the present 250-6

Smart move. A milquetoast 350 that needs a rebuild is worth about as much as the Tuesday special at Papa Murphy’s Pizza….
Keep your eyes peeled for an actual deal that doesn’t require you to spend all your budget just to get a run of the mill running V8.

 

[Elliot W]

If you are sticking with a sbc (non LS) in the future and on a budget, I'd recommend staying with a 3 speed or 4 speed (you'd save around $1k not having to buy a muncie 4 speed). Yea the OD of a 5 speed is nice, but you'd need to switch over to a hydraulic clutch which can add up especially on top of your newly acquired engine. Getting a 5 speed would need (with estimates):
-transmission ($750)
-clutch master cylinder with heim joint and fittings ($100)
-an fittings and line ($50)
-clutch slave cylinder ($40)
-transmission crossmember ($100)
-possibly flywheel and clutch kit ($200)
-probably new driveshaft length ($varies)
-probably new slip yoke ($100)

Would be much easier to keep the 3 speed unless you really want that OD gear.

 

[KnockingDiesel]

I ran across a good built 350 for $1000. My truck is a base 6 cylinder 1981 that runs good, on an original 6 cylinder with 80,000 miles on it. I'm the second owner and bought from a friend who was the first. So, if I get the motor what upgrades must be done...

Tires, wheels, rear locker in my 12 bolt rear, new front brakes (already disc) and a power booster to get power assist.
should I bolt it to my saginaw 3 speed (on the floor now) or upgrade to a 4 or 5 speed?

A new dual exhaust is mandatory ( I wonder if I need cats?)

What does everybody think. My budget is limited so the project will be phased..

You’re in Denver? My in-laws live there, I have been there in the winter with ice all over, 2wd with locker requires extra attention on ice. I was parked on the street while it rained then Turned to ice at night. Next morning as I was pulling away I suddenly lost traction (drove onto ice) and back of my truck swing out 90 degrees. I didn’t punch it, I live in New Mexico we get cold and snow but not like Denver. My open diff and lsd trucks don’t react nearly as violently on ice as one tire spins before the other. Just fyi.

Also Denver had some strict emissions testing, I went with my brother-in-law to register a 2000 Dodge Durango. They put a sniffer in the exhaust, plug in obd2 and run it on a Dyno. So if your truck is not exempt that’s something to consider. Your truck is older so it maybe different for you. Some states exempt trucks after 25 years old or over certain gvwr.

I’m not trying to be disparaging just a something to think about.

 

[deucecoupe]

I'm finishing up a similar swap in an '84 C10. I'm getting past the emissions and cat converter requirements by converting to Oregon Special Vehicle plates. It is my shop truck and will easily stay under the 1,500 mile limitation for using the plate.

I had to buy: motor mounts, upper clamshells, headers and exhaust pipes, a tall water pump and pulleys to match my p/s unit, trans crossmember, brackets for p/s and alternator, and new body mounts. I'm using this opportunity to replace the brake booster and do a brake job. So not too bad cost-wise.

I've got a '70 250 head and two-barrel intake manifold if you decide to go that way. I'd make you a good deal if you want them, trying to clear out extra parts in my shop.

Good luck,

 

[justhorns]

I've got a '70 250 head and two-barrel intake manifold if you decide to go that way. I'd make you a good deal if you want them, trying to clear out extra parts in my shop.

Good luck,

I'm interested in the cylinder head. PM Me?

 

[GTX63]

One of our square bodies (1980) was originally a 6 cylinder that was swapped for a 350 just before we bought it. The guy had the oe exhaust manifolds, pumps and accessories from the truck the V8 came from, so, other than new motor mounts and some hoses, exhaust pipe and mufflers, his out of pocket was pretty good. And, from 6 banger removal to driving out of the garage with the 350 was Saturday morning to Sunday afternoon.

 

[justhorns]

I'm now working on replacing the integrated head with a head from a 1970 nova 250. Its gonna have headers, Offy intake, and an Edelbrock 4 bbl rebuilt by little girls.