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

wanderinthru

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Ran across a late 60's C 50 with a 366, and a 465(?) 4 speed. Were the 4 speeds 465's then?
How much trouble would the interchange be? Motor mounts, electric, and radiator is what I see?
Say 366, unless the engine is all but new inside it will be bored to 427. Am I correct to understand bore, pistons and rings are the difference in the 2?

Thanks guys!

Shakey
 

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That 366 is going to be a 4-ring tall deck engine. You can make it a 427 by boring it out... but why bother? If you are going to go into the motor that much, why not just get a Mark IV 454 in decent condition? If it is a 4-speed manual in a late 60's C50, it will be a 465. They could also have come with several different 5-speed manuals and also a 5-speed allison automatic.
 

AyWoSch Motors

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Ran across a late 60's C 50 with a 366, and a 465(?) 4 speed. Were the 4 speeds 465's then?
How much trouble would the interchange be? Motor mounts, electric, and radiator is what I see?
Say 366, unless the engine is all but new inside it will be bored to 427. Am I correct to understand bore, pistons and rings are the difference in the 2?

Thanks guys!

Shakey
The 366 is a taller deck height. I believe it shares a head with a standard big block, but that's pretty much it. There aren't any aftermarket "speed parts" made for it, just stock style replacement parts.
As far as fitting it into a squarebody, I've never seen it done, but I dont see why it couldn't be done. The bottom end of block is the same dimensions as a normal big block, so it should fit physically, and you'd just use a standard 4 core big block radiator.
And the trans is the same, so it should fit with no issues, plus, the bolt pattern is the same, so you could put any trans you wanted in it.
 

wanderinthru

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That 366 is going to be a 4-ring tall deck engine. You can make it a 427 by boring it out... but why bother? If you are going to go into the motor that much, why not just get a Mark IV 454 in decent condition? If it is a 4-speed manual in a late 60's C50, it will be a 465. They could also have come with several different 5-speed manuals and also a 5-speed allison automatic.
What is a Mark IV 454?
 

AyWoSch Motors

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What is a Mark IV 454?
A standard 454, aka Gen 4, first generation for the 454, also included the 396 and 427. I think the 366 is also technically a gen 4, but not sure.
Gen 1s are the 349 and 409.
They made Gen 5 454s also, those are the mid to late 90s TBI and vortec style.
 

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Two, key parts, are different besides the block. Since the block is taller, the intake manifold is wider, and the distributor is taller. As stated, no aftermarket intake or dizzy.

The engine could have a 2 barrel carb or 4. The 4 barrel was a square bore, very small bores.

I don't remember that engine ever having an HEI dizzy, but you could covert the point dizzy to something else. The distributor is one part that may not clear the stock firewall. The dizzy was even taller in the engines that had the Holley governor. The rotating control was mounted in the dizzy right below the breaker plate.
 

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Two, key parts, are different besides the block. Since the block is taller, the intake manifold is wider, and the distributor is taller. As stated, no aftermarket intake or dizzy.

The engine could have a 2 barrel carb or 4. The 4 barrel was a square bore, very small bores.

I don't remember that engine ever having an HEI dizzy, but you could covert the point dizzy to something else. The distributor is one part that may not clear the stock firewall. The dizzy was even taller in the engines that had the Holley governor. The rotating control was mounted in the dizzy right below the breaker plate.
Wrong.

No problem buying distributor or an aftermarket intake for the peanut port tall deck engine. The new intake will work with most aftermarket heads out of the box
There are kits that are spacers that allow a standard deck intake to be used, (spacers/gaskets).
This Dart intake requires a slight bit of machining for stock heads.
You can get an aftermarket intake that is cast with a "low hole" for the stock standard height distributor or a longer one that drops right in the tall deck location.
This application done with a Dart AirGap intake.

https://www.summitracing.com/parts/CRT-M4530 is the fuel pump used.

You must be registered for see images attach
 

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Can you not stroke and bore the hell out of a tall block? 540 anyone? 496 crank and garbage can pistons?
 

wanderinthru

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Wrong.

No problem buying distributor or an aftermarket intake for the peanut port tall deck engine. The new intake will work with most aftermarket heads out of the box
There are kits that are spacers that allow a standard deck intake to be used, (spacers/gaskets).
This Dart intake requires a slight bit of machining for stock heads.
You can get an aftermarket intake that is cast with a "low hole" for the stock standard height distributor or a longer one that drops right in the tall deck location.
This application done with a Dart AirGap intake.

https://www.summitracing.com/parts/CRT-M4530 is the fuel pump used.

You must be registered for see images attach
That 366 is going to be a 4-ring tall deck engine. You can make it a 427 by boring it out... but why bother? If you are going to go into the motor that much, why not just get a Mark IV 454 in decent condition? If it is a 4-speed manual in a late 60's C50, it will be a 465. They could also have come with several different 5-speed manuals and also a 5-speed allison automatic.

Two, key parts, are different besides the block. Since the block is taller, the intake manifold is wider, and the distributor is taller. As stated, no aftermarket intake or dizzy.

The engine could have a 2 barrel carb or 4. The 4 barrel was a square bore, very small bores.

I don't remember that engine ever having an HEI dizzy, but you could covert the point dizzy to something else. The distributor is one part that may not clear the stock firewall. The dizzy was even taller in the engines that had the Holley governor. The rotating control was mounted in the dizzy right below the breaker plate.
Ok, big reason for this engine, first it's free. Truck is a bobtail grain truck that will be converted to a trailer to tend wheat drills. Trans questions were because it has the PTO needed for this same 75. Second this is my welding/work truck, it doesn't need to be a hot rod, but move alot of weight around at 55 mph and less more often. From what I have understood and experienced is these tall deck engines are awful stout down low. Believe the truck it's going into is geared 4:10, probably weighs between 8 and 9 thousand. Understand the big block will make it even heavier.

Far as carbs go, well it's set up on propane right now, so will get a carb that can be mounted to the intake thats on it. If memory is correct the propane "carbs" were made to fit stock intakes?>?

Thanks guys, This isnt a done deal yet, am working at coming up with the worth of the old truck.

If the old cab were in better shape, I would just put a bed on it, convert it back to gas and make it my welding/haul truck.
 

AyWoSch Motors

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Ok, big reason for this engine, first it's free. Truck is a bobtail grain truck that will be converted to a trailer to tend wheat drills. Trans questions were because it has the PTO needed for this same 75. Second this is my welding/work truck, it doesn't need to be a hot rod, but move alot of weight around at 55 mph and less more often. From what I have understood and experienced is these tall deck engines are awful stout down low. Believe the truck it's going into is geared 4:10, probably weighs between 8 and 9 thousand. Understand the big block will make it even heavier.

Far as carbs go, well it's set up on propane right now, so will get a carb that can be mounted to the intake thats on it. If memory is correct the propane "carbs" were made to fit stock intakes?>?

Thanks guys, This isnt a done deal yet, am working at coming up with the worth of the old truck.

If the old cab were in better shape, I would just put a bed on it, convert it back to gas and make it my welding/haul truck.
Sounds like a perfect deal to me. I'd go for it.
 

wanderinthru

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Sounds like a perfect deal to me. I'd go for it.
Sounds like yet another project for an old fat man. Lol, may help, give me the HP to go ahead and break the old truck in half????
 

Bextreme04

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A standard 454, aka Gen 4, first generation for the 454, also included the 396 and 427. I think the 366 is also technically a gen 4, but not sure.
Gen 1s are the 349 and 409.
They made Gen 5 454s also, those are the mid to late 90s TBI and vortec style.
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.

Ok, big reason for this engine, first it's free. Truck is a bobtail grain truck that will be converted to a trailer to tend wheat drills. Trans questions were because it has the PTO needed for this same 75. Second this is my welding/work truck, it doesn't need to be a hot rod, but move alot of weight around at 55 mph and less more often. From what I have understood and experienced is these tall deck engines are awful stout down low. Believe the truck it's going into is geared 4:10, probably weighs between 8 and 9 thousand. Understand the big block will make it even heavier.

Far as carbs go, well it's set up on propane right now, so will get a carb that can be mounted to the intake thats on it. If memory is correct the propane "carbs" were made to fit stock intakes?>?

Thanks guys, This isnt a done deal yet, am working at coming up with the worth of the old truck.

If the old cab were in better shape, I would just put a bed on it, convert it back to gas and make it my welding/haul truck.
I'd still be looking at just getting a running 454 from any square or a TBI truck out of a junkyard. They are basically the same engine as that 366, except without the tall deck. The 366 and 427 are different block castings and you can't bore out the 366 to a 427 without thinning the cylinder walls significantly. The 454 dyno sheet looks identical to a 366 dyno sheet, just with about 30 more of both HP and Torque everywhere in the chart. The tall deck does absolutely nothing for power. The only benefit to the 366 will be that as a medium duty engine it has a forged crank and rods. Boring it out a little bit and running higher compression pistons will wake it up a lot. A decent low RPM torque cam and decent oval port heads will help it even more.

Here's a site that I came across that seems to have a lot of specific info about those engines. https://www.tradecraftspecialties.com/bbckb
 

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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.
 

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