Crate engine swap advise please?

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73 C10

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Hi,

I'd like to swap in more hp. It's going to be a daily driver. I've got about $2500-$3000 to spend, but I'd like to stay under to $2500. I looked at the Summit catalog. I like the vortec but it's about $3000 and would require buying headers. I would also like to stay carbureted.

What can I do?
 

Old77

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If you're wanting to stay in the 2500-3000 range then either rebuild what you have or find another 350 for cheap and rebuild that swapping in some performance goodies for more HP. Another option is to search CL and do an LS swap (either 4.8 or 5.3) but you'll want to stay fuel injected on those but it's a better route for DD purposes. Why do you want to stay carb'd?
 
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350runner

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Old77 said:
If you're wanting to stay in the 2500-3000 range then either rebuild what you have or find another 350 for cheap and rebuild that swapping in some performance goodies for more HP. Another option is to search CL and do an LS swap (either 4.8 or 5.3) but you'll want to stay fuel injected on those but it's a better route for DD purposes. Why do you wanted to stay carb'd?
This^^^ plus the local warranty helps....

Sent from the dust in front of you!
 

DoubleDingo

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Vortec doesn't require headers. My stock exhaust bolted right up no problem. You'd like the vortec 350.
 

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My vortec was $2000 to my door.
 

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If you're wanting to stay in the 2500-3000 range then either rebuild what you have or find another 350 for cheap and rebuild that swapping in some performance goodies for more HP. Another option is to search CL and do an LS swap (either 4.8 or 5.3) but you'll want to stay fuel injected on those but it's a better route for DD purposes. Why do you want to stay carb'd?

LS motors can be run with a carb just fine.

https://www.youtube.com/watch?v=jvp00bKq6mI

You must be registered for see images attach
 
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Old77

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Yes I know they can be run with a carb but thanks :handshake: just not sure why you would when fuel injection is light years better
 

MikeB

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A couple things:

It's pretty to hard to beat the base GM Goodwrench engine for $1500-something delivered. Add an aftermarket intake, small 4bbl carb, and dual exhausts, and you have a very nice daily driver & cruising motor. And all your accessories will bolt up. I speak from experience, having installed three of them over the years, one in my own 69 C10, the others in a 73 Nova and 51 pickup. The power has always been a pleasant surprise, given the mundane cam and heads.

Regarding stock 73-87 exhaust manifolds bolting up to Vortec heads, well, yes they will. HOWEVER, the Vortec exhaust ports are raised, so your stock manifolds will probably cover up the top .100"-.125" of the port openings. And that's where exhaust flow is the most intense! The good news is cast iron manifolds an be easily opened-up to match the port height. Just make sure to use a 1.5"x 1.5" gasket.
 
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Green79Scottsdale

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OP... Look at buying the long block for $1500 and swap in a better cam before doing anything else. A Summit cam can be had for under $100, bringing your total in under $1600. Everything else from your truck will bolt up to it. Some carb re-tuning will be required, but that is about it.


Regarding stock 73-87 exhaust manifolds bolting up to Vortec heads, well, yes they will. HOWEVER, the Vortec exhaust ports are raised, so your stock manifolds will probably cover up the top .100"-.125" of the port openings. And that where exhaust flow is the most intense! The good news is cast iron manifolds an be easily opened-up to match the port height. Just make sure to use a 1.5"x 1.5" gasket.

Good info on the Vortec heads. I did not know about that.
 

Skweegle89

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I just dropped that $1500 crate in my k10 and I'm happy with it. I won't do a cam swap until the warranty is up, but it's got good torque down low the way it is. I took my high rise off and put a performer intake on and some new headers. Put a nice quadrajet on it from @Quadrajet Power and it runs like a top.


Sent from an old rotary telephone.
 

Green79Scottsdale

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I just dropped that $1500 crate in my k10 and I'm happy with it. I won't do a cam swap until the warranty is up, but it's got good torque down low the way it is. I took my high rise off and put a performer intake on and some new headers. Put a nice quadrajet on it from @Quadrajet Power and it runs like a top.


Sent from an old rotary telephone.



I forgot to mention that swapping cams right away voids the warranty, good point. For stock replacement, what you did is spot on. The OP mentioned more horsepower, that is why I mentioned the cam swap.




On another note, if you don't mind setting up an electric fuel pump, the L31-R long block is a great value at around $2000. Vortec heads, roller cam, four-bolt mains, one-piece rear main seal, and 9.5:1 compression. The $1500 long block I am thinking of has none of this.
 

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Good info on the Vortec heads. I did not know about that.

I didn't either. Now I want to grind my exhaust manifolds to improve flow. And the truck already runs leaps and bounds better than it did with the stock heads and cam. I could just imagine what doing some gasket matching grinding would do for added performance...:)
 

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Good info on the Vortec heads. I did not know about that.

You can see what I'm talking about here. Notice how the ports are raised relative to the bolt holes, especially noticeable in this picture on the two center ports.
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And here's better gasket for a 96-99 350 C1500 350. I think it's 1.5" x 1.5". FelPro #1444 would be a better choice, because it has a steel core. But they may not seal some some headers with goofy port shapes. Cast iron manifolds have lots more sealing surface area.

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68post

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On another note, if you don't mind setting up an electric fuel pump, the L31-R long block is a great value at around $2000. Vortec heads, roller cam, four-bolt mains, one-piece rear main seal, and 9.5:1 compression. The $1500 long block I am thinking of has none of this.

I think this is by far and away the best GM crate deal ! (And I'd really be tempted to change the cam one this one too. Only 191* intake duration :yawn:)
 

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