305 vs 350

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Iheartmy85gmc

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Hello all!
I am looking for everyone’s two cents on this topic. My issue is I am going to be replacing my engine at some point and I am faced with the question. Do I stick with the 305 my baby came with, or do I do the 350 upgrade?? There’s a lot of back and fourth online as to what’s the better option and I would like to know y’all s opinion. Please share!
 

DoubleDingo

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If you're replacing it go with 350. Direct bolt up if I'm not mistaken.
 

82sbshortbed

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I think the only difference between them is piston size. So I would go 350 for the extra horsepower. All your bolt on upgrades like intake, headers and such will cost the same. Might as well have extra horsepower for around the same cost.
 

4WDKC

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350 the 305 has smaller cylinders that limit performance head options.
 

HotRodPC

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Wow !!! Really??? There's back and forth??? That's a No Brainer. Take at look at the cost of a rebuild kit + machine work to rebuild your Wee O Five, vs buying a new crate 350 delivered to your front door, then ask yourself the same question.
 

shiftpro

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They never should have put a 305 in these trucks. The trucks are too heavy. You don't actually get better mpg with less cubes, you just get an overworked, under powered engine.
My 383 on propane uses the same amount of fuel as my 'pane 305, but has a lot more power!
 

Derrick

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They never should have put a 305 in these trucks. The trucks are too heavy. You don't actually get better mpg with less cubes, you just get an overworked, under powered engine.
My 383 on propane uses the same amount of fuel as my 'pane 305, but has a lot more power!
I never understood LP powered trucks is it more of a Canadian thing?
 

shiftpro

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I never understood LP powered trucks is it more of a Canadian thing?
What part don't you understand Derrick? I'm happy to explain..
Pane was equally popular in Canada as the US in the early 90s. It was a fraction of the cost of gasoline. Problem was the dual fuel conversions.. never worked right. The timing is different from gas to 'pane, so dual fuel was a terrible compromise.
IMO 'pane is far superior but hard to find stations that pump it, and the tanks are a drag if you don't have the room.
 

Frankenchevy

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e85!!!! lol
 

Iheartmy85gmc

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Definitely sounds like the 350 is the way to go! I thank you all for your imput. I looked around and found a remanufacturer that sells the 350 completely rebuilt and shipped for $1286 + $385 core charge that they pay shipping for too. That’s the best price I’ve seen so far.. not too bad I think.
 

Jrgunn5150

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What is that? Is that the fake gasoline that rots out all rubber gaskets and fuel line?

Boost juice.


Definitely sounds like the 350 is the way to go! I thank you all for your imput. I looked around and found a remanufacturer that sells the 350 completely rebuilt and shipped for $1286 + $385 core charge that they pay shipping for too. That’s the best price I’ve seen so far.. not too bad I think.

That's not a bad price, the Goodwrench 350 is up to like 1800 plus shipping nowadays.
 

1987 GMC Jimmy

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I forget the code for the truck 305, but it probably gets the silver medal for the types of 305s built. The heads on it are not bad at all, better than almost every other 305 head and some other 350 heads. I do agree, though, that they don’t really belong in the truck unless you did some pretty healthy upgrades, and doing stuff to a 305 is not as cheap or quite as universal as doing the same to a 350. I’d go with the 350 for sure, but with that said, the 305 doesn’t deserve all the hate it gets. I think if they wouldn’t have made the choked down emissions versions and would have kept them only for the types of trucks that would have come with a 4.1L, it wouldn’t have gotten such a bad rap. A K10 long bed should not have come with a 305, though.
 

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