350 to 454

[68c20lwb]

i am buying a 84 454 4 bolt main tommorrow, going to replace my 74 350 2 bolt main. includes everything except for the carb and alternator. 454 was mated to a SM465 as is my 350 which makes it even easier!

[Turo209]

Nice... I did the same to mine... I got a 454 from a el camino ss that was wrecked... On these trucks u have to move the engine mount back 3 inches cause a big block bottom pulley is going to be very close to the front cross member.... Goodluck
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[68c20lwb]

ive heard from lots of people that it is a direct drop in?

[Fullpower]

Originally Posted by 68c20lwb

ive heard from lots of people that it is a direct drop in?

...............Answer: Affirmative.
On a 1974 chevy pickup, the 454 WILL indeed bolt right in place of a 350.
You will of course need the proper FLYWHEEL with balance weight for the 454.
Motor mounts, distributor, starter, alternator will bolt up.
Fuel pump, water pump and of course exhaust headers will need to be spec'd for the big block.

[68c20lwb]

well i have a 68 pickup, i have the correct flywheel that was mated to a SM465 just like mine. so i do need a fuel pump, have a water pump and exhaust headers. the motor mounts are the same, but the same location?

[Captainfab]

The '68-'71 trucks used a different motor mount bracket on the frame as well as a different motor mount for the big blocks. Those positioned the engine in between the small block location and the I6 location. Of course this wouls also require you to move your bellhousing crossmember forward. That can be a lot of work. Physically the 454 will bolt in, in the same location, and with the same motor mounts as the 350 did. It just won't be in the factory location. Consequently, factory big block components may not fit correctly. I'm not sure if your headers will clear the small block motor mount brackets or not. The big block motor mount brackets had an indented area for the exhaust manifold clearance.

[68c20lwb]

I have the big block top bracket, and the small block bottom bracket. so do you think my valve covers and or dizzy cap will hit the firewall?
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[68c20lwb]

The headers are also shorty headers by the way, so they should fit.
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[Captainfab]

I don't think the '68-'71 big block motor mounts will work with the small block frame brackets.

Originally Posted by 68c20lwb

I have the big block top bracket, and the small block bottom bracket. so do you think my valve covers and or dizzy cap will hit the firewall?
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[crazy longhorn]

Originally Posted by Captainfab

The '68-'71 trucks used a different motor mount bracket on the frame as well as a different motor mount for the big blocks. Those positioned the engine in between the small block location and the I6 location. Of course this wouls also require you to move your bellhousing crossmember forward. That can be a lot of work. Physically the 454 will bolt in, in the same location, and with the same motor mounts as the 350 did. It just won't be in the factory location. Consequently, factory big block components may not fit correctly. I'm not sure if your headers will clear the small block motor mount brackets or not. The big block motor mount brackets had an indented area for the exhaust manifold clearance.

I agree with Captain fab on this....your BB will set in the sb stands/mounts, but it will be header clearance that is the issue. On the sb mounts/stands, your BB will be an inch or so too far foward(not too big an issue on the nose), & all on the back should clear. If you are running streetrod shorties, you might bolt it in & see how it goes. You might also opt for a set of POL tubular brackets/mounts to gain a little clearance. The last suggestion is only speculation on my part, as I have not tried it to verify.....crazyL

[68c20lwb]

Thanks guys, thanks to all of you. Keep uP with the information and suggestions, it is really helping me out! I love this forum and it is so helpful!
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[crazy longhorn]

Originally Posted by 68c20lwb

Thanks guys, thanks to all of you. Keep uP with the information and suggestions, it is really helping me out! I love this forum and it is so helpful!
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Post up any pics you can, & any ? as you go.....that way we can ALL learn a new trick or 2 crazyAl

[1970C10truck]

Originally Posted by crazy longhorn

Post up any pics you can, & any ? as you go.....that way we can ALL learn a new trick or 2 crazyAl

I'm also interested. I have been thinking about the same swap and can't seem to get any information that jives with what anyone else says.

[Captainfab]

Here's a pic of the '68-'71 big block motor mounts and brackets.

[68c20lwb]

Originally Posted by crazy longhorn

Post up any pics you can, & any ? as you go.....that way we can ALL learn a new trick or 2 crazyAl

here is my 454 thread...

http://67-72chevytrucks.com/vboard/s...d.php?t=453732

[68c20lwb]

thanks for that photo of those mounts, anyone selling them?