Opinions on an Engine Swap for 81 C10

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Backfoot100

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It should also be noted that there really isn't any need to have a newer block to run a roller setup. You can run a roller cam on an older block by using retrofit lifters with the link bar and having a cam button on the timing cover. You also need a melonized gear on the distributor and a correct roller cam.
Very true. I did exactly this retrofit when I built a 383 stroker for my boat.
The only problem is the retrofit setup is rather pricey. You go this route you also need to measure and replace the push rods because the roller lifters are much taller than flat tappets.
 

TPISly-C10

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6L LS so cheap, reliable, powerful, good on gaz millage, easy to maintain ect....but i understand the nostalgic value of the old small block! ;)

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ceejay

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6L LS so cheap, reliable, powerful, good on gaz millage, easy to maintain ect....but i understand the nostalgic value of the old small block! ;)

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That sure is pretty.
 

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#3 (KISS) method, everything as mechanical as possible to keep the aftermarket parts vultures at bay!!!
 

ceejay

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Found a block on Facebook marketplace today. Any opinions? It's $100.

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Bextreme04

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Found a block on Facebook marketplace today. Any opinions? It's $100.

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It's either an L31 block or a crate engine block. I'd go check it out and see if it has a fully reamed fuel pump rod hole. Take a rod with you and see if it slides right in. If so, you have a great base to start with. If its a crate engine block that is machined for the fuel pump rod, you can order a full 383 rotating assembly, new summit vortec heads, nice hydraulic roller cam and lifters, and then hit up a junkyard for the spiders, plates, and bolts for the hydraulic roller setup.
 

MikeB

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I'd go with option #3. I ran the basic 350/265hp Goodwrench engine in a 69 C10 for several years, and it worked great with an Edelbrock #1406 600 cfm carb and dual exhausts. It made good torque at low-mid RPM and got decent fuel mileage. I also put them in a friends' vehicles -- a 55 Chevy car and a 51 Chevy pickup, both with 600 CFM vacuum secondary Holley carbs and headers. Yes, the heads and cam are anything but performance parts, but the engine is certainly not a dog, especially if used to replace a tired, stock 305.

That was back when you could buy the engine for $1200-$1500, but the price has gone way up since then. Today I might go with GM #19420873, a 330hp 350 with more compression and better heads. Or maybe an entry level 350 from Blueprint or ATK.

As for a used L31 Vortec, odds are the heads will have hairline cracks. Several years I bought a used L31 engine, and it turned out both heads had minor cracks. I ended up buying new GM Vortec 062 heads, a balanced rotating assembly, GMPP RamJet roller cam, and on and on. Turns out I spent almost as much as the 330hp 350 crate motor would have cost!

On that $100 #880 block, do what was suggested above. Then, if it has a standard bore, I'd jump on it. If over-bored, I'd want to mic the bores to make sure they don't need to go out to anything more than +.040". Keep in mind that the block may also need to be decked and line honed, depending on its history.

And if you don't have the budget for a roller cam setup, there's nothing wrong with a flat tappet cam if it's properly broken in using something like Driven BR30 break-in oil. None of the engines I mentioned above, along with others that I've built, have had valvetrain issues.
 
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Rhett Croley

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Is there a brand of crate you would recommend? Blueprint? GMPP?


I put a Blueprint 350 sbc in my son's '87 k10 a few years back. It came with new cast block, carb, intake and flywheel. Basically it was a vortec motor with a cam with a dyno sheet showing 375chp for $3800 delivered. It ran great but dropped a cylinder at @3k miles. Blueprint took it back and sent me another. It's been running great since. Not too thrilled about 2x remove and install but they made it as painless as possible and overall I am happy with the purchase.
 

greyghost

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Right now, I have an extremely tired 305 and I'm ready to swap it out. Now I've bounced around different ideas, but not sure on which route to take. I think I've narrowed it down to wanting a 350. I don't want to do LS swap or big block. I've done some research and I've come down to:

1. Buy a used 350 sbc from same era and slap my accessories on and roll.
2. Buy a Vortec 350 sbc from '97 - '00, possibly swap in a better cam, put carb intake on it and be done
3. Buy a crate 350
4. Buy a used 350 block, get it machined, rebuild it, etc.

The problem I have with 1 & 2 is the motors around me are all 200k+ mile motors and I'm concerned about the longevity.
The problem I have with 3 is price.
The problem I have with 4 is that I've never rebuilt an entire motor. While I really want to learn how to, this is my daily driver and I'd rather rebuild one on the side and take my time and learn.

What would you guys do/have you guys done? Of course I want more power, and I'm trying to stay under $1500 for everything.

Thanks.
some time has past , n curious to know how project is moving along and cost of to present/finished? to add lil info to thread of doing rebuild yourself is not something i'd recommend without some education beforehand eg. highschool engine class, college coarse of mechanical theory. some of tools needed for SBC will not be cheap, micrometers 1"- 4" , inside mic gages or telescoping gages, pullers, ring compressors n file, dial indicator, torque wrench, feeler gauges, cyl. hones small n large, hand tools metric n fractional sockets 1/2" ,3/8, 1/4, wrenches 1/4- 1 1/4, spring compressors. not to mention electronic testers , well over thousand in quality tools, storage box? in todays technology era, LS to me is cheapest route, finding a 2000+ silverado wrecked, low miles, working tranny, buy the who truck for under 500, if you have the storage work at your pace, engine, tranny, wiring harness ecu, getting ecu modified for swap is not difficult, depending on vehicle, stock gauges, fuel pump n tank .fuel injection, so on. carb more expense intake, regulator this is my way for my '81 swb in process gathering all necessary parts for project keeping budget as cheap as possible, search local first , fb , auto trader, newspaper, salvageyards...hope your project is finished, if not soon to be, i'm on 1 yr unless the auto gods step in early n project must move forward sooner...
 

greyghost

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Right now, I have an extremely tired 305 and I'm ready to swap it out. Now I've bounced around different ideas, but not sure on which route to take. I think I've narrowed it down to wanting a 350. I don't want to do LS swap or big block. I've done some research and I've come down to:

1. Buy a used 350 sbc from same era and slap my accessories on and roll.
2. Buy a Vortec 350 sbc from '97 - '00, possibly swap in a better cam, put carb intake on it and be done
3. Buy a crate 350
4. Buy a used 350 block, get it machined, rebuild it, etc.

The problem I have with 1 & 2 is the motors around me are all 200k+ mile motors and I'm concerned about the longevity.
The problem I have with 3 is price.
The problem I have with 4 is that I've never rebuilt an entire motor. While I really want to learn how to, this is my daily driver and I'd rather rebuild one on the side and take my time and learn.

What would you guys do/have you guys done? Of course I want more power, and I'm trying to stay under $1500 for everything.

Thanks.
expect alotta luck for $1500 w/ economy. I got a 2000 chevy metro 400K still runs, but very rough, i think couple burnt valves, new tires, i have spare engine from my '92 has rebuilt head ,simple head swap 2 or 3 yrs left in her..50mpg...your not gonna rebuild nothing of quality for 1500. cept buying used car. a LS swap is your cheapest route, way more HP on pump gas, eliminate $8 octane booster every fillup,OD tranny, just watch or talk to local police for 2000+ chevy truck that got rolled over weekend, $300 you got whole truck, motor mounts $20 modified ECU $50 or ck amazon $1500 sb 350 gen II change cam out to add 40-50 hp, headers another 10-20hp. without a warranty dont expect much. plenty books on sbc, not difficult , money is in tools, save ya from paying middleman, still $1000 in special tools, but $500 in new parts, micrometers, ring compressor , spring compressor , torque wrench, I rebuilt my 327 yrs ago spent less than grand parts n tools, but in todays economy , noway...this is why I'm going LS 5.3 gen 4 in my '81 swb, getting all parts first '87 fuel tank, , ECU, Flywheel n mnts from amazon, tank LMC , using all 81 acc. i can , no ac. have door wings n floor vents. truck was 300 w/blown up tranny, 4sp factory in '81 , HD clutch. and hoping to be started in 1 yr time, no rush, after all parts, are acquired . thats start date, tank first and installed, then ECU and wire harness next, then mounts n clutch, possibly new bell housing depending on clutch disc needed, spline n size dim.keepin it simple until i know condition of 5.3. good or bad next one is ready to go cheap...take engine course at local trade school, only pay for parts needed, all tool free or discounted. i took mine in high school, 5 groups of 3ppl we each got a local persons motor to fully rebuild, they paid for parts n we got education...win win...good luck. keep us all updated on your decisions..
 

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