Swapping an 81 454 into a 74 pickup.

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rumblebox

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Is there anything I should know regarding fitment before I do this? Is it as simple as it should be?

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HotRodPC

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Of course you're aware the exhaust will have to be changed. Fan shroud is likely to be different.
 

rumblebox

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Got those covered. Doing headers and E fans

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Honky Kong jr

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The extra weight may also need to be considered. If your front springs are weak with the SB they are gonna be a lot weak with 300+Lbs more sitting on them.
 

rumblebox

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The extra weight may also need to be considered. If your front springs are weak with the SB they are gonna be a lot weak with 300+Lbs more sitting on them.
I should have clarified its going in place of another 454.

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Honky Kong jr

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I should have clarified its going in place of another 454.

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Oh then it should be a slam dunk. That was pertinent info.lol
 
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HotRodPC

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Oh it's just a drop in swap them. Piece of Cake. You can do this one in your sleep.
 

rumblebox

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Oh it's just a drop in swap them. Piece of Cake. You can do this one in your sleep.
Just making sure there are no subtle differences between the year models.

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gmachinz

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The only thing I can think of is to correctly add the HEI 12V coil lead from the firewall bulkhead. 1974 is a one year only style bulkhead connector.

In 1974 there aren't any provisions for a 59-series male terminal-only 56-series. On your '81 GM used a larger terminal for both the coil feed and the main BAT bussbar feed off the firewall junction. I'd recommend upgrading the alternator tho to at least a 63-amp unit if not already equipped.
 

rumblebox

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I got the 6 trans bolts off, and it will not break loose from the block. Are there any im missing?

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gmachinz

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Did you unbolt the torque converter from the flex plate?
 

rumblebox

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Did you unbolt the torque converter from the flex plate?
It's a manual. It just needed a lot of persuasion since it hadn't been out in like 30 years

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gmachinz

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It's a manual. It just needed a lot of persuasion since it hadn't been out in like 30 years

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Ah...I didnt catch that part!
 

rumblebox

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Back to its former glory, and then some, soon enough.
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rumblebox

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Nice rod cap...
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