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79' Chevy Big 10
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I am starting a rebuild on my 350 for my Chevy pickup 79 model Big ten and I could use some help from experts on where to start, it's all factory stock, the engine block number is 3970014 if that helps. I would like to have a econo -rod , this truck has the 3/4 ton rear-end, known as the "heavy half". I had copper head gaskets in mind to be a good fit. Where do I begin, need some direction, guidance. Help!
 

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For the money , convenience , reliability , , look at crate motors . They start at around $2 k & go from there . OR , see if there's a local engine builder that has a good rep & is reasonable . With the initial outlay in tools , parts cost , lack of good machine shops & the learning curve , especially on old small blocks , its honestly hardly worth it any longer ...YMMV
( honestly thought I'd never say this !)
 

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I am starting a rebuild on my 350 for my Chevy pickup 79 model Big ten and I could use some help from experts on where to start, it's all factory stock, the engine block number is 3970014 if that helps. I would like to have a econo -rod , this truck has the 3/4 ton rear-end, known as the "heavy half". I had copper head gaskets in mind to be a good fit. Where do I begin, need some direction, guidance. Help!
If your engine is tired and need of a rebuild you need to access what type of engine you want. If you just want a stock 350 then yes as mentioned previous a crate engine is one option. If you want something more, you need to do some homework. You said the rear end is a 3/4 ton unit. What gear ratio is it. The code should be on the RH axle tube. It is stamped on the tube. You will have to get the numbers and letters and reference the letters in a manual or online. If you want a more customized engine for your truck, as mentioned find a reputable machine shop. I personally have my block work machined on a CNC. It is more accurate than what you have dimensionally now. If you find a shop like that they can help you with your selection of parts and they can get them for you. You can also ask on this site. There are more than capable people on here to help you. Don't be afraid to interview the machine shop, the more you understand the more satisfied you will be with the end result. Just my $.02 hope it helps.
 

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If your engine is tired and need of a rebuild you need to access what type of engine you want. If you just want a stock 350 then yes as mentioned previous a crate engine is one option. If you want something more, you need to do some homework. You said the rear end is a 3/4 ton unit. What gear ratio is it. The code should be on the RH axle tube. It is stamped on the tube. You will have to get the numbers and letters and reference the letters in a manual or online. If you want a more customized engine for your truck, as mentioned find a reputable machine shop. I personally have my block work machined on a CNC. It is more accurate than what you have dimensionally now. If you find a shop like that they can help you with your selection of parts and they can get them for you. You can also ask on this site. There are more than capable people on here to help you. Don't be afraid to interview the machine shop, the more you understand the more satisfied you will be with the end result. Just my $.02 hope it helps.
Crate motors of ANY performance level are available ( some with warranty) from Blueprint engines , Shafiroff performance, White performance, Competition products , jegs & summit , Pace performance . just to mention a few . Where I live , the closest performance engine builder is 100 miles ( and he's not that good & horribly overpriced !!)
 

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There are plenty of shops in the DFW area.
I lived in Little Elm for awhile, but was only doing bodywork back then. Not hotrod, so no recommendations here.
 

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1979 Big ten chevy 2 wheel drive truck, is this the trailering special? If so, they are very unique as in 78/79 if the vehicle was designated for pulling a trailer from the factory, it was emission exempt. Easy way to tell is check the intake manifold, it should not have a EGR valve. It should have a 12 bolt rearend but with larger drum brakes and 5x5" bolt pattern. front disks are the wider 1.25 rotors, larger radiator.
A stock rebuild with a cam of 260 or less duration (summit 1102), Edelbrock rpm dual plane intake, vacuum 600 carb should work well. The cylinder heads are most likely 624 castings, these were a light weight casting and very prone to cracking. Better heads with 64 chambers would wake it up. If it has the long tailshaft turbo 350, they are a good trans, if it was designated for trailering it would have a slightly modified modulator and govener for higher rpm shifts. simple rebuild on these transmissions are cost effective. It would be a great daily driver with increased torque from the higher compression and mild duration cam. I had a 78 and it worked out well. Forget about copper head gaskets, i always use Felpro brand composite gaskets and never had a failure. You may think it is a 4 bolt main block, but not necessarily so. Gm used many 4 bolt blocks in trucks but the assembly line never stops, so if you discover it is a 2 bolt, don't fret. SBC's don't have bottom end problems unless severely abused or lack of oil changes and maintenance. Just my opinion, good luck on your project.
 

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Guess I am not sure what is meant by "econo-rod" so maybe that needs further explanation.

The things that needs to be done first are simple. Determine exactly how you plan to use the truck when it's finished. This is totally your call and it can be anything that you want. Next determine what the budget is going to be for the project. Budgets can be broken down into individual projects such as a rebuilt engine, then a rebuilt trans, then paint and body work, etc. And the last in this case is to determine if the engine you have is a rebuild-able candidate. Not much point in trying to rebuild an engine that has too many issues to be successful. You will need to figure out what the condition of your engine currently happens to be. If it is running, does it burn oil, smoke from coolant leaks, start easy or hard, have decent compression or is it broken in some other manner? If it is not running, why? Or do you know? This can make it much harder to move forward with this engine.
 
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I assume by econo-rod you're looking to do this on a budget. Good thing is the chevy 350 gives you a solid base, but a lot of what you spend also depends on how hands on you are. How good is the engine from what you know? Is it a 4 bolt main or a 2 bolt? leaks? compression? bearings & cam? Do you know how to check these things, or know someone who can do these checks for you? Assuming the engine is a 4 bolt main that checks out and has no serious issues, you can do a simple top end upgrade, definitely a cam and a manifold, heads/valves if you want to splurge, open up the exhaust with some headers and throw in a hotter ignition. Depending on who does the work you you can get this done on a budget, most of these parts are available from summit and even on ebay if you don't mind looking around. If the engine is a 2 bolt or its leaking and tired then it might just be better to look at a crate motor, machine shops can get very expensive and you still have to buy all the parts. hope this helps, keep us posted on your progress, good luck!
 

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It’s not that the 350 is a dud when ‘built’ even in those heavy, square late 70’s pickups ( I owned a 78 Scottsdale once upon a time after building a pretty stout 350, I pulled it out for a 454) so where I sitting is putting a 383 stroker is only a few bucks more and will deliver a lot more torque which is what most pickup owners are searching for.

The 350 for the year have and really from 1972 to 1996 is a pretty neutered motor even without EGR as on some models. The root problem being low compression, a lazy cam, hardyly any ignition advance, lean carburetion combined with really lazy burning, overly large combustion chambers. These are the thinks that need to be addressed, emission equipment takes all the blame but compared to the lack of the performance fundamentals in the design of the major components of these engines, power losses to emission equipments is somewhere in the minor noise level. You need to fix the fundamentals not the bolt on factory junk. Not that you shouldn’t remove that stuff if you can, but removal alone won’t change much in terms of torque and power. This applies to your 350 and whether you use it as a 383 base build.

I have no idea what copper head gaskets would do by themselves, they are usually applied to high output engines that require the cylinders be O ringed to insure the compression seal, otherwise these things tend to leak what you can’t afford to lose.

Basically you need to get the compression up, these days that falls pretty hard on cylinder head and piston selection. Everything else just tails into that. To that end your basically looking at heads whether factory like the L31 Vortec of 1996 or the plethora of import and domestic aftermarket heads. The piston crown shape makes the bottom side of the chamber; the factory round dish being the least efficient burner of mixture, the flat top or D dish are quantum’s better at converting mixture to power. The other criticality is squish/quench clearance between the surfaces of the piston crown and the step of the combustion chamber. The less area overlap as occurs with a round dish piston combined with a greater clearance for any piston shape the more prone the engine is to detonation and preignition. So maximizing the effects of squish/quench builds what is called mechanical octane which permits getting more power from the fuels at the corner station. Done right this makes the fuel behave as if it’s octane is 4 to 7 points higher than its pump rating.

To pull this off takes some prior planning as the squish/quench clearance needs to be from .035 to .045 inch for a street engine. This counts the distance of piston crown to the deck and the thickness of the head gasket. For a cast iron head this isn’t too hard to deal with as there a several steel shim gaskets that are .015 to .019 inch in thickness that gets a standard block and piston/rod assembly beck clearance of .020 to .025 inch into the neighborhood of the total clearance. But if you choose an aluminum head then you’re looking having to use a thicker composite gasket the thinnest being .026 inch. This forces you into getting the block’s head decks milled (called “decking“) so this trip wire need to be thought out ahead of time.
Most makers of aftermarket heads also duplicate what the make in aluminum in cast iron as well, so there is some flexibility here.

The L31 Vortec factory head uses a unique intake bolt pattern so these add an intake purchase to your parts list most aftermarket heads are machined for the 1955 through 1986 bolt pattern and the Vortec 1996 through current crate engines of that style. The 1987 through 1995 is an oddball that looks like the early pattern but changes the angle on the bolts by the plenum, just something to watch out for as there are sellers that try to pass off these oddball 87-95 LO3 and LO5 heads as Vortec’s, so you need to keep your wits about you when head shopping. The LO3 and L30 are the shrunken head versions for the 305 in those years.

Come back with questions, they are easier and cheaper to answer than it is to correct bad decisions.

Bogie
 

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I've had good luck using the basic Goodwrench 350 crate engine. It's not a hot rod engine, but with a small 4 bbl, headers, and a proper ignition curve, it works surprising well. I have installed them in a 69 C10, 55 Chevy car, and a 52 Chevy pickup . Transmissions were TH350 and 700R4. Axle ratios ranged from 3.08 to 3.55.


All the external parts from your 1979 350 -- brackets, exhausts manifolds, flex-plate, etc. -- should bolt right on. It will rev to around 4500-5000 RPM, but its strength is low-mid RPM torque, just what a 3/4 ton pickup needs for working in the 2000-3500 RPM range. A VERY mild performance cam will make a bit more TQ and HP at slightly higher RPMs.
 

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Discussion Starter #12
It’s not that the 350 is a dud when ‘built’ even in those heavy, square late 70’s pickups ( I owned a 78 Scottsdale once upon a time after building a pretty stout 350, I pulled it out for a 454) so where I sitting is putting a 383 stroker is only a few bucks more and will deliver a lot more torque which is what most pickup owners are searching for.

The 350 for the year have and really from 1972 to 1996 is a pretty neutered motor even without EGR as on some models. The root problem being low compression, a lazy cam, hardyly any ignition advance, lean carburetion combined with really lazy burning, overly large combustion chambers. These are the thinks that need to be addressed, emission equipment takes all the blame but compared to the lack of the performance fundamentals in the design of the major components of these engines, power losses to emission equipments is somewhere in the minor noise level. You need to fix the fundamentals not the bolt on factory junk. Not that you shouldn’t remove that stuff if you can, but removal alone won’t change much in terms of torque and power. This applies to your 350 and whether you use it as a 383 base build.

I have no idea what copper head gaskets would do by themselves, they are usually applied to high output engines that require the cylinders be O ringed to insure the compression seal, otherwise these things tend to leak what you can’t afford to lose.

Basically you need to get the compression up, these days that falls pretty hard on cylinder head and piston selection. Everything else just tails into that. To that end your basically looking at heads whether factory like the L31 Vortec of 1996 or the plethora of import and domestic aftermarket heads. The piston crown shape makes the bottom side of the chamber; the factory round dish being the least efficient burner of mixture, the flat top or D dish are quantum’s better at converting mixture to power. The other criticality is squish/quench clearance between the surfaces of the piston crown and the step of the combustion chamber. The less area overlap as occurs with a round dish piston combined with a greater clearance for any piston shape the more prone the engine is to detonation and preignition. So maximizing the effects of squish/quench builds what is called mechanical octane which permits getting more power from the fuels at the corner station. Done right this makes the fuel behave as if it’s octane is 4 to 7 points higher than its pump rating.

To pull this off takes some prior planning as the squish/quench clearance needs to be from .035 to .045 inch for a street engine. This counts the distance of piston crown to the deck and the thickness of the head gasket. For a cast iron head this isn’t too hard to deal with as there a several steel shim gaskets that are .015 to .019 inch in thickness that gets a standard block and piston/rod assembly beck clearance of .020 to .025 inch into the neighborhood of the total clearance. But if you choose an aluminum head then you’re looking having to use a thicker composite gasket the thinnest being .026 inch. This forces you into getting the block’s head decks milled (called “decking“) so this trip wire need to be thought out ahead of time.
Most makers of aftermarket heads also duplicate what the make in aluminum in cast iron as well, so there is some flexibility here.

The L31 Vortec factory head uses a unique intake bolt pattern so these add an intake purchase to your parts list most aftermarket heads are machined for the 1955 through 1986 bolt pattern and the Vortec 1996 through current crate engines of that style. The 1987 through 1995 is an oddball that looks like the early pattern but changes the angle on the bolts by the plenum, just something to watch out for as there are sellers that try to pass off these oddball 87-95 LO3 and LO5 heads as Vortec’s, so you need to keep your wits about you when head shopping. The LO3 and L30 are the shrunken head versions for the 305 in those years.

Come back with questions, they are easier and cheaper to answer than it is to correct bad decisions.

Bogie
Thank you so much for all your input, I am learning more from you by read/listen to ur advice. Only I hope to f a way to show my gratitude and yes, I'll continue to post my progress.
 
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