Vortec 350 questions

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Jarhead79

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I've been looking around for a 350 to rebuild and came across one a co-worker has for $250 bucks, now I'm no expert on engines at all but I do know I can use the heads on my current 350 as an upgrade, but I'm curious as to whether or not I can just rebuild the vortec and upgrade it little by little and then carb it like my current 350, I'm trying to stay away from computers and rewiring etc. Are there any differences in the blocks from 79' to say 99 up vortec?
 

DoubleDingo

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I think the blocks are the same or very similar. I bought a crate motor in 1998, and they asked if I wanted it ready for carburetor or fuel injection. Back then it was more difficult to put a carb on vortec heads, and I didn't have access nor could I afford a fuel injection system, so I went with the carburetor long block. The only difference between the two were the heads. Nowadays there are intake manifolds made just for putting a carb on vortec heads. The rep at the dealer where I bought the block said to order internal engine parts for a 1996 block. I have the block on my patio right now, and I cannot see any difference between it and my other small blocks except it has provisions for driver side and passenger side dipstick.
 

Jarhead79

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Ty for the info, I'm just torn on building a motor or rebuilding my current, I'd rather build one and swap than pull mine then build it, I like driving my truck too much but have another to drive. Just have to get to a starting point and dive in! Lol
 

kleedus

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a vortec is a factory roller cam motor you can get the ht383 cam and run stock roller lifters.

the ht383 cam is not a monster cam it should run good

and you can get a 383 crank and make it a 383

the gm performance parts ht 383 is rated at
•Horsepower: 340 at 4500 RPM
•Torque: 435 ft/lbs at 4000 RPM

I had a vortec 350 rebuilt at a local machine shop and I had him copy the ht 383 specs

and the vortec heads would be a lot better you can get cheap carb intakes on ebay. I think they are pro comp intakes I bought one good quality.

the motor pictured is a 99 vortec 350 with a old metal timing chain cover and the carb intake
 

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kleedus

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oh ya if you run the roller cam you will need to use the distributer drive gear from a vortec distributer or a bronze one. or the cam will chew it up
 

77 K20

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The old metal timing chain cover would be nice- as the vortec covers did not have a timing indicator on it. The HT383 cover is made of plastic and does have a timing indicator on it- but it is worthless. Barely sticks out and only hits the back edge of the balancer and it is almost impossible to see it.
 

85c10owner

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oh ya if you run the roller cam you will need to use the distributer drive gear from a vortec distributer or a bronze one. or the cam will chew it up

GM recommends a melonized distributor gear when you use their camshafts. Most aftermarket cam companies offer roller camshafts with the cast gear option to allow use of a stock gear. You just need to ask the company you get the camshaft from.

As far as differences as mentioned the timing cover is different. And most if not all vortec blocks have the mechanical fuel pump boss but are not drilled. This is a easy fix at a machine shop. And you will need a flexplate/flywheel for a 1 piece main engine as the 1979 blocks are 2 piece. They are balanced different as well. Other than that there is no reason why you couldnt rebuild the vortec engine and put a carb intake on it and run it.
 

Jarhead79

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Cool info guys thanks, this will probably be a long term build unless something happens and I gain a few grand extra in the not to distant future. I'm not hp hungry but 350/400 is my goal for now, I'd love to do an Ls swap but I just don't think it is in the cards right now. I'll keep looking into this though, I still need to get a drive set up for the belt and other sorted stuff I'm sure, just need to get the motor and internals sorted out and a place to disassemble and reassemble. Don't think my landlord would appreciate it in my living room! Hahaha although I did store my Harley at one point in here! Lmao
 

dougbert

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Check the link in my sig area for the FJ60 where I put a 1973 fully rebuilt 350. Has a lot of documentation on how I built it with roller CAM, etc.
Post as a Bill of Materials, part numbers and costs for each part.
Spent way too much.

I used Vortec II heads from GMPP (stronger/better than the stock Vortec I heads) in my build.

After building that thing, I wouldn't do it again. I spent too much money on it.
I will go Gen III 5.3L for a cheaper engine in the future, but I learned a lot from doing that SBC that has helped in doing my 5.3L install into my 1984 K1500, also in the sig area

dougbert
 
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Jarhead79

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Well I got some good news from a customer at my part time job at Oreillys that builds cars, he has a spare 5.3 truck with computer and wiring harness for $600, not sure if the trans is available with it but will be finding out, we are supposed to get together and discuss it, might even be able to get it installed reasonably, as much as I'd love to do it all myself, this may be the easiest! Fingers crossed!
 

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