350 to 366 swap in a 75 C 30, How much of a PIA?

wanderinthru

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Remember, free is not always the best way to go.

Just because it was free to start with does not mean it won't end up costing you way more in the long run.

If it were me to be doing, I would look for a gen 4 or gen 6 454 and go from there.
It might be more up front, but it has a better chance of being finished and running with far less hassle.

I found this out while building aircooled VW engines.
I got a smoking deal on a forged rotating assembly, but the extra machine work that it takes has the whole thing sitting on the shelf. It is waiting for me to spend the $1000 on a new engine case.
Then the other $5000 in parts can be used, but it is a waiting game.
Makes sense, though I can do most if not all of the machining myself.

@Bextreme04 , Do appreciate it, will study the info on the site. Finding a 454 local has been challenging, have found a few, but seen to be way over priced, or rebuilt for a hot rod type application. Hell just bought 13 Chevy engines, 6 small block v8's 2 running, 4 292's 2 running, rest ate 250's all with bell housings, couple with radiators, and a diesel out of a 1466 International for a grand. I am a tight ***.
 

Bextreme04

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Makes sense, though I can do most if not all of the machining myself.

@Bextreme04 , Do appreciate it, will study the info on the site. Finding a 454 local has been challenging, have found a few, but seen to be way over priced, or rebuilt for a hot rod type application. Hell just bought 13 Chevy engines, 6 small block v8's 2 running, 4 292's 2 running, rest ate 250's all with bell housings, couple with radiators, and a diesel out of a 1466 International for a grand. I am a tight ***.
I get it, the being able to do the machining yourself is a big one. It's interesting how different things are prevalent in different areas. I seem to see a ton of 454's around here for dirt cheap and never see any 366/427 or 292/250's. Everything is either a 350 or a 454 and you can't throw a rock without hitting a dozen "ran when pulled" adds asking for $150 to take it off their hands.
 

wanderinthru

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I get it, the being able to do the machining yourself is a big one. It's interesting how different things are prevalent in different areas. I seem to see a ton of 454's around here for dirt cheap and never see any 366/427 or 292/250's. Everything is either a 350 or a 454 and you can't throw a rock without hitting a dozen "ran when pulled" adds asking for $150 to take it off their hands.
Tons of old bob tails around here, 366's were real popular in them. These I bought were old irrigation engines, that's all went electric submersable now. Got in the trailer load deal, because of a set of camel hump heads for the race car. Though I do believe 3(?) of the v8's are 283's or 327, which I want for the race car as well.
Do appreciate the info.
 

bucket

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Around here, 454's are still a bit difficult to find and when you do, it's around $1200 for a basic one with somewhat unknown running condition.

A 366 probably isn't much to write home about, as it's barely any larger CI than a garden variety 350 that can be built so cheap. But on the other hand, it's still a free big block, lol.
 

AyWoSch Motors

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TBI is Gen V, Vortec is Gen VI... they are different. For instance not all Gen V are roller cam, Gen VI is all roller cam and no mechanical fuel pump boss.
Ah, didn't know the vortec 454 was considered a gen 6. Good to know.
I got most everything else right tho, Haha.
Is the 8.1 BBC that they used in Avalanches in the early 2000s also considered a gen 6?
 

AyWoSch Motors

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Makes sense, though I can do most if not all of the machining myself.

@Bextreme04 , Do appreciate it, will study the info on the site. Finding a 454 local has been challenging, have found a few, but seen to be way over priced, or rebuilt for a hot rod type application. Hell just bought 13 Chevy engines, 6 small block v8's 2 running, 4 292's 2 running, rest ate 250's all with bell housings, couple with radiators, and a diesel out of a 1466 International for a grand. I am a tight ***.
Holy cwap, that's quite the haul.
You willing to sell any of the 292s, my buddy that bought your grill guard has been looking for one.
 

wanderinthru

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Holy cwap, that's quite the haul.
You willing to sell any of the 292s, my buddy that bought your grill guard has been looking for one.
Oh yea, all of them are for sale, why you think I bought them? Lol. They are set up for natural gas, will need a carb, some have HEI, some are still points. he get that grill guard on?
 

AyWoSch Motors

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Oh yea, all of them are for sale, why you think I bought them? Lol. They are set up for natural gas, will need a carb, some have HEI, some are still points. he get that grill guard on?
Nope, was about to, them the engine in that truck brok a pushrod and ate threw the cam, so now the engine has to come out.
As soon as he gets that back together, it will be going on.
 

wanderinthru

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Nope, was about to, them the engine in that truck brok a pushrod and ate threw the cam, so now the engine has to come out.
As soon as he gets that back together, it will be going on.
Of course, what kind of engine?
 

AyWoSch Motors

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Of course, what kind of engine?
454.
92 k3500 dually, TBI. Cool truck... when its running.
Itll be fine, we already pulled it, and tore it down. Hes gonna put in new bearings, because he doesnt trust them after it having so much cam shavings in the oil. Needs new rear main, new lifters, new pushrod, and hes probably gonna do some sort of RV cam or similar upgrade while it's out.
 

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Ah, didn't know the vortec 454 was considered a gen 6. Good to know.
I got most everything else right tho, Haha.
Is the 8.1 BBC that they used in Avalanches in the early 2000s also considered a gen 6?
No sir.
The 8.1 is kind of its own animal from what I remember.
Our junkyard has had several big blocks in it over the last couple of years.
I have parts from 4 of them and a complete one waiting to be rebuilt.
 

bucket

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The glorious 8.1 was the "LS-ified" big block. As far as the electronics and fuel system, it's just like swapping in an LS.

So when people say "sheetcan it, LS swap it", that could mean an 8.1 big block @SquareRoot
 

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Ah, didn't know the vortec 454 was considered a gen 6. Good to know.
I got most everything else right tho, Haha.
Is the 8.1 BBC that they used in Avalanches in the early 2000s also considered a gen 6?
8.1 is a Gen VII BBC. While the Gen V and Gen VI are almost completely interchangeable parts-wise with a Mark IV, the Gen VII is almost completely different and shares much more with the LS engines than with the BBC family. The head bolt pattern is different, so cylinder heads are one of a kind on them. It also uses the LS pattern motor mounts and the internally mounted reluctor ring on the crank for spark trigger.
 

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That C50 may be running the SM420, it too has the provision for the PTO. If it has a bulge on the passenger side it's a 420.
 

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That C50 may be running the SM420, it too has the provision for the PTO. If it has a bulge on the passenger side it's a 420.
What year is the C50? 1967 should be the last year of the 420. We have a '67 C50 with the 420 and a '68 C50 with a 5 speed.
 

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