305 Swap To ???

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85longblack

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Hello. New guy here. I recently bought a 1985 C10 with the 305 (sadly). I do not want to jump on the LS bandwagon (no offense) but I do want to swap it out for something beefier. I am not looking to drag race and the truck will not be a daily driver. It is a toy for me and the wife to cruise in. Are there any major benefits to using a Vortec set up as opposed to ordering a somewhat built 350? How difficult and expensive is the Vortec swap? Thanks for any help.
 

Shorty81

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Welcome from Ohio. I'm old school, I'd recommend big block. I'm old, drive around gently and my 496 is surprisingly better on fuel than my last truck with a 350.
 

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SquareRoot

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I have Vortec. I wouldn't do it again. For the money there are better options. If you have a 700 trans, you have two issues.
 

Turbo4whl

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I also would recommend a BB. When I pulled the 305 out of my '82 I slipped in a 1971 402 BB. Bored .030 over made it about a 406. Mild RV cam made it a torque machine.

Many BB's to chose from and they slip right in. You need different rubber engine mounts and they bolt to different holes that are already in the cross member you have.

Best to get an engine that still has the engine accessories, ie the PS pump, alternator etc, as the brackets are not the same as the small block.
 

RecklessWOT

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Vortec engines are decent, but they're nothing so amazing that I'd go out of my way to swap in. Getting a beefed up crate 350 is the easiest most straightforward thing you can do. Pull that 305 out and use it as a boat anchor (or sell it to someone who needs to run one for their class of racing), slap the crate motor in and call it a day.

Though like others have said, I too personally am a fan of big blocks (and just like you I am not fond of LS swaps). It's all up to you, but yeah I wouldn't waste the time/money going with a vortec, they're good engines for what they are and sure there are some advantages, but a built regular 350 would be awesome and your easiest/cheapest route.
 

85longblack

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I had honestly not given much thought to a big block but
all of your comments make perfect sense. All I know for sure is that 305 has to go!
 

tadslc

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I am in the process of changing out my 305 and went with a crate 350. Absolutely the simplest, least expensive option.
 

84c10Tony

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I am not looking to drag race and the truck will not be a daily driver. It is a toy for me and the wife to cruise in.
If you would like some great info...check out Rich Weyand's posts here, awesome intelligent guy with common sense.

"Simplicity and Torque".

My ol' 84 with a 305/700r4 cruised just fine, (even better with a Detroit Tru-Trac and 3:73's). Got 18mpg right off the bat during break in.
Best was 22mpg with tailgate between 45-60 deg.

The 3:73's Really woke up the 305, I can almost imagine running it with an RV cam, intake and long tubes.

I would have enjoyed Rich's suggestion for the win...I didn't get to it.
Growing up around hot rods in east Detroit, cruising Gratoit Ave etc., in mild to wild, his idea for low cost basic fun is the best I have seen.

How ever one looks at, Enjoy!, we only get so much time, so much money.
 

Asgeir

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I was in the same boat, for my 84, it had a 305 that was dead. Got a 350 SB TBI from a 87 and made it a 383. I was 50/50 on the LS swap, wanted to keep it old school.
 

potent rodent

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i would go 383 a lot cheaper to build than a big block, trust me i know from experience.
 

Ricko1966

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So you're not going to drag race it,you do want to cruise in it. Buy a rust bucket 5.7 tbi burb,swap gas tank, wiring,engine and rear end, small cam,underdrive pulleys,headers,electric fan. Decent milage excellent drivability,and enough balls to tow with. Yea not all burbs had better rear gears but 10-1 you're going to end up with better gears. This is really a dirt simple swap
 

quaddriver

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The big one
Is GM still selling the toluca 350 drop in (check out jegs and summit or jim pace) that makes 260? hp using duals and a 4bbl - something that will be childs play, even if you install 2 cats.

the L31 head vortecs tho...you cannot beat the breathing without going LS or spending twice (or more ) the budget on foreign heads for a gen1 SBC. not a single pair of the gen1 heads flow worth a damn without 20 hours under a grinder, humps and casting proofs be damned

your best bang for the buck will still be a boneyard LS...they make more power just sitting there and you can install dizzys and carbs all day and in case you wanna go EFI everyone is flashing. I just inherited a '13 GMC WT with the 4.8 that makes more factory hp than every SBC ever installed in a truck and most that were installed in a car. hard to say no...

someone mentioned the 700R4...85 was a magic year where the pump was beefed up but there are more mods SINCE that you will want and most are DIY if you have a few tools lying around.
 

Ricko1966

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Big block small block ls, will always be a debate. Naturally aspirated. a very mild 454 makes more horsepower and torque than a factory ls1 ls2 ls3 ls 6. Nothing complicated about the swap. No modifications neccesary. As for reliabilty I guess people don't remember thousands of people each year used to jump into big block motor homes, and drive them across country with out fear.
 

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