Convert to 350 vortec

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Miez

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Hi all,
My 350 in my 78 C10 is a bit tired and I’m considering swapping with a 91 350 vortec I have lying around.
The vortec needs a rebuild first.
Which parts should I get at minimum?
I’m in The Netherlands and can get parts easy from the USA through work for at least this year.
So I would like to get as much as possible without taking the vortec apart today.
What parts would you guys recommend?
I already have the gasket kit, alternator, waterpomp, oil pump, bolts, Edelbrock performer intake and a Holley 600.

What camshaft should I get for a bit more horsepower?

Any other parts I already should get? I get that i should take it apart first to decide what’s needed internally like bearings at minimum but maybe more like pistons etc and the block reworked.

What electric fuel pump should I get to make work in my C10?

Anything else you can think about?

Cheers!
 

Hilllbilly

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Check for cracks.
 

xm20k

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If you're planning to put a carb on it check to see if the fuel pump pushrod hole is drilled some were some weren't. I've seen them have block off plates were the pump goes and were not drilled for some reason. A mechanical pump is easier to deal with when running a carb. Can keep the stock fuel system intact.

What are your plans for how you are going to use the truck?
 

Miez

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The truck is not my daily driver, hobby and fun car only. However I would like to have it running in a decent way. Long time ago I had a Ford running a bit rough in idle because of the cam. I’m fine wit that as long it runs reliably.

The hole for the mechanic pump is not open. It doesn’t have that plate, just casted solidly. Is it doable to drill it open when I’ve taken it apart?
 

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I wasn’t aware the Vortec engine/heads was in existence in 1991. Before you start, are you sure it’s a Vortec if that’s what you’re after?
 

xm20k

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Now that I think of it, 86 and up are 1pc rear main roller cam blocks but the "Vortec" is 95 or 96-02. GM got confusing right before they discontinued the SBC in factory vehicles.
 

AuroraGirl

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Now that I think of it, 86 and up are 1pc rear main roller cam blocks but the "Vortec" is 95 or 96-02. GM got confusing right before they discontinued the SBC in factory vehicles.
The blocks of cars were roller, but the trucks still had flat tappet

The engines block , drilled for the keepers or whatever, yes.

The vortec wont have any provision to drive the push rod, if you have a machined boss you can use a mechanical fuel pump to simply act as a fuel pressure regulator/return block. Id suggest electric in tank (like a TBI pump) for it would be near the PSI and it would stay cool

since this is a tbi engine thats donor, not a vortec, that does change some things. but the name vortec dates to 1984 or 1985 with the 4.3l v6

The word had to do with the way the heads flowed air, the name came back for the engines starting in 1996 for the v8s
 

75gmck25

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GM confused us all by using the Vortec name multiple times. As already mentioned, a ‘91 would be a throttle body injection (TBI) engine, and it may have the word Vortec on the valve cover. The L31 Vortec engine, with Vortec 64cc heads did not come out until about ‘96.
 

Ricko1966

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If it is a 91 engine, swap your intake and ignition over,you will have to grind on the manifold in the 4 center bolt holes because they come in at a different angle NBD. Take the arm off your old fuel pump bolt it in place on the new block. I'm assuming the bolt holes are drilled and tapped. Now all your fuel lines and bypass will still work. Install an electric pump of your choosing.,pumps push better than they pull mount it low,below fuel level,near the rear,better yet in tank. But that will get you going
 
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Miez

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I wasn’t aware the Vortec engine/heads was in existence in 1991. Before you start, are you sure it’s a Vortec if that’s what you’re after?
I might have been wrong with the year. Maybe it was a 2001 express van where the engine came out of.
It’s casting # is 10243880 and it has a plastic intake manifold.
 

Miez

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If it is a 91 engine swap your intake and ignition over,you will have to grind on the manifold in the 4 center bolt holes because they come in at a different angle NBD. Take the arm off your old fuel pump bolt it in place on the new block. I'm assuming the bolt holes are drilled and tapped. Now all your fuel lines and bypass will still work. Install an electric pump of your choosing.,pumps push better than they pull mount it low,below fuel level,near the rear,better yet in tank. But that will get you going
It’s the performer 2116 intake I already have. I bought it new and was told that’s the one fitting on a Vortec engine.
For ignition, can I use the Mallory I have in my 350 in the truck currently?
 

xm20k

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Like I said GM did some weird stuff near the end mines a 02 last year and it has the pump boss and was drilled for the pushrod, and I run a carter high flow pump. If the boss is there just not drilled and you're rebuilding it anyway you could maybe have your machine shop drill it and tap the bolt bosses if they aren't done already.
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Agree with @xm20k The engine in my nephews truck used an 880 block and had the fuel pump hole drilled. The engine in my 96 Tahoe also has it and the water pump bypass hole in it that seems to be hit or miss too.

Just remembered-unless something changed throughout its run, the factory cam won't have a fuel pump lobe on it
 
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75gmck25

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Pull the valve covers and get the casting numbers off the heads. That is key info you need . If they turn out to be L31 Vortec heads, then pull the intake manifold off and also verify whether it has a roller cam spider.
 

bucket

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If it has the plastic intake plenum and a plastic timing cover, it's for sure what we all know as a Vortec block and heads.
 

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