Original or crate engine? 1976 k5 blazer Cheyenne

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Grit dog

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Yes, you're right. We're just saying it's not AS big a deal in the squarebody market as it is with say, Hemi 'Cudas. Plus the factory didn't stamp numbers on stuff like they did for the cars so it's harder to prove anyway
I know there was no such thing as numbers matching engine in GM pickups through at least ‘72. Do you know when they did start stamping vins on blocks?
Another consideration is once 1973 happened and through the 80s, basically all cars and trucks were so schitty with low power and emissions crap that no gearhead really “wants” a stock 178 hp small block with too many vacuum hoses and other crap on the engine.
Unlike the muscle car era and later models 90s-2000s when emissions got less complicated and horsepowers got bigger.
JMO
 

legopnuematic

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Numbers matching drivetrain for these trucks isn’t is important for 95% of them. Low mileage/well documented/odd combinations it might play a larger role in value. The reality is, there was never a “performance” package for a squarebody, no LS-7 454s sort of thing. They are all pretty equal minus emissions equipment levels.

With that said, if you have a good 350 core, std bore and so on, I’d be more inclined to build that provided you have a good automotive machine shop available to do the work. Crate motors have gotten quite expensive, even on the low end for stocker replacement engines, and you might get one that’s .01 overbored, or .06. 7.5:1 compression because it has short rebuilders pistons in it type of thing.

Personally I think going fuel injected is kind of a fools errand in most scenarios. The aftermarket TBI setups are not really an upgrade, power/reliability/mileage wise. Multi point injection on the other hand has the potential to be pretty good, but you are at the mercy of whoever sold the kit if parts are needed. Carburetors can be fixed with a rock and get going enough to limp home most times.
 

TotalyHucked

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I know there was no such thing as numbers matching engine in GM pickups through at least ‘72. Do you know when they did start stamping vins on blocks?
Another consideration is once 1973 happened and through the 80s, basically all cars and trucks were so schitty with low power and emissions crap that no gearhead really “wants” a stock 178 hp small block with too many vacuum hoses and other crap on the engine.
Unlike the muscle car era and later models 90s-2000s when emissions got less complicated and horsepowers got bigger.
JMO
I don't. I know you can run the numbers on the engines and if it jives with the VIN of the truck it's likely original but no way to know for sure. Hell, I don't know if they EVER started doing VINs on the engines. Even in the LS stuff, I'm not sure.
 

legopnuematic

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Partial vins yes:

From the 1979 service manual as I have it handy
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psyburn74

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Wow.. lots of opinions and good advice. Haha.. I have pros and cons about both types of drive train options and what to do. The original engine lacked power and it could barely kit 75mph at full throttle i hated that but the truck is original it smokes and the transmission leaks but still have original hub caps and the sticker. With a new engine and transmission i would get more power and overdrive which is important with today's speeds. Of course I would replace the transmission with a better one not necessarily a 700r bit it would need an overdrive. But if i have to cut into or modify the body in anyway to accommodate the new drive train that will affect my decision. The idea of this project is not necessarily and daily runner but a nice project truck that I can be proud of and show off.
 

Sad Sack

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I want to know if I Should I replace my 76' Blazer engine with a crate or keep the original and rebuild? My plan is to try to keep the value of the truck. Its all original, no modifications but it needs some work including an engine. Its planed as a project truck so it i plan to keep the rest all original, except what needs replacing eg. Carpet, dash. So should I replace the engine and transmission with a fuel injection crate and 700r transmission or rebuild the original carburetor engine and 350 transmission to get the most value when reselling? Thank you -Psyburn74
All depends on your budget and what is wrong with the original engine. Is it tired as is no compression? Threw a rod? Head gasket issues? Need more info.
 

Memaloose

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My two cents is to leave it original but that's how I am. I'd rather build a custom vehicle and have the original. There's something I find in all original vehicles, kind of like historical technology. When I was young, in my teens and twenties, I didn't keep anything stock, once I got into my 50's my views changed.
 

bucket

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Totally. Agreed. Besides, anyone who’d “upgrade” to an OE TBI or TPI still listens to too much Motley Crue, probably has 2-3 broke down Camaros in their front yard and has a can of aerosol hair spray on their vanity… unless they’re bald!

Damn. That thing about TPI and broken Camaros hits close to home, lol.
 

Grit dog

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Damn. That thing about TPI and broken Camaros hits close to home, lol.
Hahaha, comment not meant for anyone in particular.
OTOH, I have basically no use for most 80s automobile technology. No getting around it being a transitional period where, IMO, a good amount of simplicity and reliability was lost for several years.
I wrote off any benefits of early fuel injection combined with the rest of the electronics and the mother of all emissions clusters (except for early tier iv dieeel maybe) a long time ago.
 

bucket

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Hahaha, comment not meant for anyone in particular.
OTOH, I have basically no use for most 80s automobile technology. No getting around it being a transitional period where, IMO, a good amount of simplicity and reliability was lost for several years.
I wrote off any benefits of early fuel injection combined with the rest of the electronics and the mother of all emissions clusters (except for early tier iv dieeel maybe) a long time ago.

Yeah, I get it. I love TPI, but my current goal with my hot rodded Camaro is to run the TPI off an LS style engine management with coil-near-plug ignition.
 

xm20k

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I would not be concerned with numbers matching on a 1 of 1.5 million mass produced work truck we aren't talking about a super rare vehicle here. Myself if I wanted to just drop a ready to go engine and not worry about building it myself and breaking in a flat tappet cam I'd go with one of these. Roller, 350HP vs the stock 160HP and takes a mechanical fuel pump and comes with everything but carb and exhaust and maybe some minor items.

 

Grit dog

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Yeah, I get it. I love TPI, but my current goal with my hot rodded Camaro is to run the TPI off an LS style engine management with coil-near-plug ignition.
I’m not that creative. But it sounds cool!
 

edgephoto

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I would just rebuild the engine I already own. To find a good machine shop/builder see who builds race cars at your nearest track. Those guys know what they are doing. It will not be cheap but you can have some input and build it exactly as you want vs. a mass produced crate motor.

There is nothing wrong with the 700R4 transmission IF you replace the stock internals that are failure prone with upgraded parts. Do some searching around and you will find a ton of guys use these in drag cars.

One place is Bowtie Overdrive. I put one of their units behind a Jag V12 years back. Was very happy.
 

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