Have you swapped a 350 for a 454? Advice needed

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Marc Rexroad

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I am done building my 454 and putting it in my 1979 cab and chassis. Sm465 trans, 350 non AC currently.

I like to put lots of thought into what I do and am wanting the voice of experience as to what hurdles I might come across.

Can i use the mounts of the 350? I have the right pulleys and brackets rounded up.

Can someone please shoot me a pic their whose routing off the water pump? Want to make sure I don't mess up the cooling flow.

Should I pull just the engine or pull the sm465 with it? What about putting it back in....install trans on engine first? Just did a clutch not long ago and would rather not experience that trans line up from underneath again.

Should I just buy the stock 454 fan shroud or is there another cheaper option?

Anything you can add please do so. Thanks in advance!
 

AKguy

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When I swapped the 350 for the 454 on a TH400/equipped 1980 K frame, I had to relocate the engine to mount holes back about 3/8”. Not sure that helps your situation. Here’s my hose routing.

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Alaska 79 K-10

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Yes you can use the 350 mounts. But if there is a plate between the mount on the block, use that too! This is needed for proper spacing with the frame mounts.

I leave the transmission in place.

I converted over to the factory shroud
 

Marc Rexroad

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Thanks so much for the replies! I noticed that both engines that I received the pics of differ in the hose routing. The one has the small one in hose going from water pump to intake manifold and the other one does not. So it must be able to be done either way?
 

Craig 85

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1985 K30 454

Pre A/C
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Post A/C
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bucket

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Yes you can use the 350 mounts. But if there is a plate between the mount on the block, use that too! This is needed for proper spacing with the frame mounts.

I leave the transmission in place.

I converted over to the factory shroud


Your engine compartment is wonderful to look at. Clean, simple and detailed, without being flashy.
 

sirweesarunch

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This is the lower 454 hose , It actually works on the 6.2 diesel as well.


Sent from my iPhone using Tapatalk
 

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Thanks so much for the replies! I noticed that both engines that I received the pics of differ in the hose routing. The one has the small one in hose going from water pump to intake manifold and the other one does not. So it must be able to be done either way?

I used the routing specified for my setup in the manual. I ended up not being able to use my original shroud from the C20 frame as the original fan sits too tall. I am converting to electric fans anyway.
 

GMFORLIFE

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What kind of hoist lifts a big block and a transmission?
I always install the engine separately.
I always use new mounts and install new springs.
Any other items that can be done easier with engine removed..do it now.
 

bucket

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What kind of hoist lifts a big block and a transmission?
I always install the engine separately.
I always use new mounts and install new springs.
Any other items that can be done easier with engine removed..do it now.

The 2-ton hoists from Harbor Freight will lift a big block with trans on it. The old orange ones are plenty capable, along with the newer gray ones. I believe they still have coupons to buy one for $179.
 

RecklessWOT

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What kind of hoist lifts a big block and a transmission?
I always install the engine separately.
I always use new mounts and install new springs.
Any other items that can be done easier with engine removed..do it now.
Any engine hoist as far as I know. Even with the added weight of a transmission attached, we're not talking anywhere near a ton, let alone 2 tons which is what most hoists are rated for. What are we talking, 1,000lbs max? Any hoist will pick that up, a chain fall would probably even do it no problem.

I usually pull them together but install them separately. Idk maybe I've always been lucky but I've never found lining up engines and transmissions under the vehicle to be incredibly difficult. Sometimes it can be annoying, but not horrible
 

Marc Rexroad

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Thanks for all the opinions so far. The sm465 was a challenge to line up when I did the clutch but only took about 45 min. The sm465 is about 250 pounds so yes that would make it quite a load.
 
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