350 to 454 swap questions

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shealywhitt

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Whitt
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k10
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Hi all I’m a little new to this. I ended up with a 79 k10 with a sb350 and th350 trans and have been tinkering with it. Never ran right so I check compression and had zero on cyl 3 and 5. Pulled head and found an issue with the block between the two cylinders. Found a stock 454 for a reasonable price and bought it.

-It has everything carb to pan but no water pump, alternator, or power steering pump. Can those things be easily swapped from 350 to 454? Looks like they might could be?

- what headers should I go towards with the least modification and on a budget? Np 203 transfer case

-What motor mount modification needs to be done if any?

- And lastly is it even worth it to swap the motor to a 454? Its just a little project truck but I don’t want to spend a fortune to have it running and driving again.

Thanks for the advice I’m fairly new to this and new to the page. Didn’t see any other threads answering these questions so I appreciate the info. If there are other threads I apologize in advance!
 
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bucket

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Use the stock 350 mounts and brackets. You will need accessory brackets for a big block. Use headers for a big block truck, or headers for a '68+ Nova. You will need a new fan shroud for the big block, or convert to electric fans.
 

bucket

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I'll add to the fan thing. I highly recommend factory fans and shroud from either a Ford Windstar or '97+ GM fwd minivan. They fit well and work better than aftermarket fans, imho. And significantly cheaper.
 

HotRodPC

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Jep, x2 on the fans. Any OE fan will be better. Better quality and better design too. They flow better and are usually even quieter too. All good things, nothing bad. Just go to a Pull A Part type yard and get one. Sometimes even a dual fan assembly depending on what you get it from.
 

bucket

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Jep, x2 on the fans. Any OE fan will be better. Better quality and better design too. They flow better and are usually even quieter too. All good things, nothing bad. Just go to a Pull A Part type yard and get one. Sometimes even a dual fan assembly depending on what you get it from.

Yeah, the ones I mentioned are dual fans. You can get fancy with dual stage fan controllers too.
 

75gmck25

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My 350 has the stock steel bladed fan, factory shroud, severe duty fan clutch, Robert Shaw high flow water pump, and high flow 195 degree thermostat. Temps are completely stable, with only minor differences under load or with A/C on.

If you can find the factory fan and shroud for the 454, I would highly recommend it. Works and fits well and puts zero load on your electrical system. The Windstar or Taurus electric fans also work well, and they are relatively inexpensive (even new), but make sure your alternator is up to the job.
 

peats

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Hi all I’m a little new to this. I ended up with a 79 k10 with a sb350 and th350 trans and have been tinkering with it. Never ran right so I check compression and had zero on cyl 3 and 5. Pulled head and found an issue with the block between the two cylinders. Found a stock 454 for a reasonable price and bought it.

-It has everything carb to pan but no water pump, alternator, or power steering pump. Can those things be easily swapped from 350 to 454? Looks like they might could be?

- what headers should I go towards with the least modification and on a budget? Np 203 transfer case

-What motor mount modification needs to be done if any?

- And lastly is it even worth it to swap the motor to a 454? Its just a little project truck but I don’t want to spend a fortune to have it running and driving again.

Thanks for the advice I’m fairly new to this and new to the page. Didn’t see any other threads answering these questions so I appreciate the info. If there are other threads I apologize in advance!
You could probably install a known good used 350 for about $1,500. Might have to buy an entire vehicle to get the engine, just sell off what's left if that is the case. Craigslist or Facebook. I would want to see and hear the engine running. Take nothing for granted. Fresh rebuilds untested scare me on the internet.
 

HotRodPC

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Engine Size
454 - Turbo 400 - 3.73
You could probably install a known good used 350 for about $1,500. Might have to buy an entire vehicle to get the engine, just sell off what's left if that is the case. Craigslist or Facebook. I would want to see and hear the engine running. Take nothing for granted. Fresh rebuilds untested scare me on the internet.
I got one of those once. A guy bought a whole car for $500, a 75 Malibu. He was putting a SBC in his sister's Jag. He bought it just to rob manifolds, bracketry, crossmembers and such. He bought a long block so he needed all that stuff and it was cheaper to buy a whole car to get it and then parted the car out and made a few bucks and the carcass went over the scale for another $200 back. I bought the used running long block. He told me it smoked a bit at start up but it ran good and had good compression. He was spot on. We used that engine in my bro's El Camino. $100 long block 350. He ran it for 8 years towing a lawn trailer til it finally developed a light rod knock but it ran fine. He ended up buying a pick up truck and sold the El Camino AS IS with the rod knock, but we sure got the $100 worth out of that engine. It used about quart of oil every 1000 miles for those dried up valve seals.
 

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