Value of a 400/402 big block?

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Grit dog

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I know there are better options for building big power, but say a guy had an opportunity to get a good running 400 big block out of a ‘72 C10 for say, cheap….
Seems like a cool engine to drop into any square. Particularly an older one.
Obviously it’s worth whatever a decent running takeout motor is at a minimum, but cool factor, semi-period correct, and a big block…
I have no current use for it, but seems like I can’t pass it up for a couple hundred bucks considering my buddy is looking to get it out of his shop.
If I don’t take it, he’s liable to trade it for a set of headers or something….
 

Shorty81

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I know there are better options for building big power, but say a guy had an opportunity to get a good running 400 big block out of a ‘72 C10 for say, cheap….
Seems like a cool engine to drop into any square. Particularly an older one.
Obviously it’s worth whatever a decent running takeout motor is at a minimum, but cool factor, semi-period correct, and a big block…
I have no current use for it, but seems like I can’t pass it up for a couple hundred bucks considering my buddy is looking to get it out of his shop.
If I don’t take it, he’s liable to trade it for a set of headers or something….
I'd pick that up in a heartbeat.
 

Dooley

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If it was close I would grab it.
My 1972 GMC 3500 Wideside had one stock.
I wish i still had that truck. Factory in dash tach.
402, 8.5' long pickup box, under bed right side tool storage box, and auxiliary left side 18 gal. fuel tank.
 

Salty Crusty

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There's a reason many reject a 396/402 in favor of 454's: POWER

Even the 4.250" standard bore big blocks have issues with the big combustion chambers of big block heads, many builders notch the tops of the bores to help it breathe. This problem is magnified with the smaller bore 396/402 block. This causes problems with fuel efficiency and emissions. And you won't make as much power as an LS 5.3.

Now take that 3.766" stroke out of a 402 and drop it into a 454 block and you'll have a 427. Short stroke/big bore, the recipe for power.

It's sitting around in his shop for a reason...
 

45tt

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I recommend picking it up, even if you just flip it for profit.

I had one in my old 72 Custom Camper and I loved it.
 

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@Salty Crusty
For sure. He’s building a bigger, easier to build engine. For all the reasons you mentioned basically.
 

Grit dog

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I recommend picking it up, even if you just flip it for profit.

I had one in my old 72 Custom Camper and I loved it.
Yeah, can’t really just flip it on him. Bro code, right?
But thinking more about buying a cool solution to a problem I don’t have yet…
I wouldn’t want to build it either. Have looked into it and bang for the buck isn’t there compared to other/easier options. iMO
I may just find an excuse to hang a boat anchor on my engine stand for an undetermined amount of time. Lol.
In the meantime, as long as it’s not going anywhere it looks better taking up space in his shop than mine!
 

Salty Crusty

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And in a few years, you'll get to pass it along to another friend..and so on, and so on....
 

bucket

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When I was younger, a guy I know offered to sell me the 396 (402) from his '70 Nova SS. It ran and performed nicely. I still kick myself for not buying it.

I also kick myself for not trying to buy the 4-speed from him as well, lol.
 

Grit dog

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And in a few years, you'll get to pass it along to another friend..and so on, and so on....
Right? Probably after I have to build a cart to roll it into a moving van or something ridiculous!
And that’s why it’s still in his shop, but I’ll probably do something silly and buy it anyway
 

Salty Crusty

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^ been there, done that...if it's cheap, no harm, no foul. You might find somebody with a late 60's muscle car that wants it, it's a great feeling to facilitate someone's restoration.
 

Allan Abley

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Sounds like it is hard to pass on an offer like that.
 

JeffK10America

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I’ve experienced a 402 .. like to have one now for my chevelle . There good engines !
That’s a good buy for that engine!
 

Turbo4whl

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The 1972 402, if it still has the factory heads will have the same heads used on the 454s. Fully quenched combustion chamber that work just fine with hi-dome pistons. The earlier heads did have hot spots.

You will need to machine and add hardened exhaust valve seats. Mild RV cam will build lots of torque!
 

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