RIP 340 Onto Magnum swap

autopar3000

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At 160K, I bet it still has a good crosshatch.
Mine did with 150k miles (240k km), but it was an ambulance that got fleet maintenance. On the other hand it probably spent a ton of time idling. It has the typical cylinder head cracks but that doesn't bother me one bit. I hear a lot about cracked Magnum heads and very little about those engines dropping valve seats.
 

plumkrazee70

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Sorry, haven't updated this thread. As luck would have it, I found a 69 340 local to me std bore for $100. It was just the block (no caps).

I took it to the machine shop, with my old caps, to see if he could fit them on to the new block.

He hot tanked the block, magnaflexed it, sonic checked it and it all turned out to be good.

He was able to machine the caps and line hone them no problem. So I'll just need a .005 under timing chain.

He is going to move forward with my rotating assembly in the new block.
 

RammerJammer75

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Sorry, haven't updated this thread. As luck would have it, I found a 69 340 local to me std bore for $100. It was just the block (no caps).

I took it to the machine shop, with my old caps, to see if he could fit them on to the new block.

He hot tanked the block, magnaflexed it, sonic checked it and it all turned out to be good.

He was able to machine the caps and line hone them no problem. So I'll just need a .005 under timing chain.

He is going to move forward with my rotating assembly in the new block.
That's a heck of a find!
 

go-fish

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What was the deal with your block? Needed a couple sleeves right?
 

plumkrazee70

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What was the deal with your block? Needed a couple sleeves right?

Yea, unfortunately. It was disappointing because it had been rebuilt in 2013, ran very few miles before we decided to do a complete resto mod. So the motor sat, even tho it was bagged and indoors, moisture got inside the cylinders and rusted.

The cylinders were already.040 and beyond cleanup at .060.
 
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