Any ideas on this 340 block ?

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72SwingerJosh

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I found this ad for a 340 block on market place and it has me a little puzzled. It has a cast date for the year 1978. The block looks pretty rough and I’m not sure it would clean up or not. Anyone have any ideas about it? Here are the ads pictures, I cut and pasted them to here.
4F39E390-56F3-4724-A644-51569A638442.jpeg
EDCF7302-7448-4544-9A3D-557427F8F9B2.jpeg
2BD5A350-17DC-4DFC-94E5-22FBE6444AF6.jpeg
BE8463A4-7ADA-4E89-8EA1-7C9512C2D381.jpeg
D87CE085-AC7C-419E-A0F7-5F430DBC0F9B.jpeg
D81BAA8F-F198-4493-8031-3385A8E40942.jpeg
 
It’s possible it was an over the counter replacement block but that is just a wild guess. Other than that, I can’t even come close to explain it.
 
Yep, ‘73 block. Just curious, what are they asking for it?
 
I looked at that last week. Def. a 73 'but won't ship from Mo.
 
I wonder how much will have to be taken off the head surface and cylinders..?
 
Being as it's a 73 cast date & it's measuring 4.060 on the bore, it needs to be checked over by a good machinist & then sonic tested to see if it will clean up at 4.070 or 4.080.
 
Being as it's a 73 cast date & it's measuring 4.060 on the bore, it needs to be checked over by a good machinist & then sonic tested to see if it will clean up at 4.070 or 4.080.
I do agree, 400 dollars for that 73 340 block as it sets, seems very pricey for a block in that shape, could be a boat anker...
 
If you want/need a 340 block there is a vendor (Mega Parts) out of NW Wisconsin that have several 340 blocks on listed on various sites including FB Marketplace. They seem to be in better condition for similar money. Mega Parts has a website too with a lot of mopar restoration parts. I would think that they'd be willing to ship since it is a pretty good size business.
 
Whenever there’s that much rust, it’s rare to see one clean up at less than .040 over to get past the pitting.
 
Depending on the OP's location, there may be better candidates available.
 
I wouldn't pay $400 for that gamble.
If you found a non rusted standard bore block that passed a magnaflux and sonic test for $1,000 you would be money ahead in the long run if you must have a 340.
Good luck, and let us know how this turn out.....
 
I wouldn't pay $400 for that gamble.
If you found a non rusted standard bore block that passed a magnaflux and sonic test for $1,000 you would be money ahead in the long run if you must have a 340.
Good luck, and let us know how this turn out.....
I have some
 
I would not fool with that block.
Rough as a Corn Cob!!
You can find a decent one for a little more.
 
If some of you don't mind 8 sleeves I know where there's a sleeve to standard 340 block all machined and squared up and they want $1,000 for it
 
If you want/need a 340 block there is a vendor (Mega Parts) out of NW Wisconsin that have several 340 blocks on listed on various sites including FB Marketplace. They seem to be in better condition for similar money. Mega Parts has a website too with a lot of mopar restoration parts. I would think that they'd be willing to ship since it is a pretty good size business.
@tinman2 I'm curious why you disagreed? I've purchased small parts from them in the past with no issues.
 
I wonder when they stopped casting them ? Would 2-7-73 be a late casting ?
maybe one of the last ?
 
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