Magnum...not cracked!!!!!

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71scamp78

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Ok I got a 96 magnum engine tore apart and it appears to me the heads are not cracked between the two exhaust valves like 90% of them are. Here's a pic of one head they both look the same and I don't see a crack all I see is the impression of the old head gaskets. So did I get lucky or what
 

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Pull the valves out and you might see something.

I've had a couple that had valves pounded right in that didn't warrant a look.
 
They crack right here in the seats, and usually all four corner cylinders.
 

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71scamp78 said:
On the four corner cylinders so 1 7 2 8..that's weird
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I thought so.
I am just taking a guess from investigating the whole thing, but it looks to me like the Induction "hardened" seats are just a little too hard causing them to be fragile under heating and cooling cycles.
Kind of like dropping a hot marble in cold water.
 
pull valves, have them tanked and mag'd. The seats get microscopic cracks hard to see with naked eye sometimes, specially if yoiu have old eyes like mine....almost forgot, cross your fingers too:D
 
I think the 90% figure you quoted is exceptionally high and due to internet gurus. I have had and torn down about 6 pairs and none were cracked. I also have a friend who has never found one cracked. Not that I am arguing that they do not crack, but I think it's exaggerated.
 
This could also be another location thing. Maybe in colder climates than the south east, they crack more, since there is more of a temperature change. Just food for thought.
 
RustyRatRod said:
This could also be another location thing. Maybe in colder climates than the south east, they crack more, since there is more of a temperature change. Just food for thought.
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I thing RRR might be onto something as they rarely are not cracked here in Wisconsin.
have heard of more than a couple guys going threw several sets of heads to find 2 un-cracked. for rebuilding.
 
I think its more of an aluminum/plastic chinese radiator issue. Now, that said, hotter or extreme cold climates will stress out a pos radiator much more than a temperate climate so in reality, its probably related to both extreme climate and pos factory rad.

In the end, if you count on them being cracked you wont be disappointed when they are. If you consider the price of a valve jov, valves, springs etc... then EQ's at under a grand are a deal. You also get the bonus of a nice HP increase just by bolting them on.

Pishta, it only matters as much as your engine does...if it drops a valve, seat or fills cylinder with coolant, will it matter? In our shop, we dont even use factory mag heads anymore, they all get EQ's.
 
hope everyone is well, have a quick question what do the engine remanufacturers do with the heads for magnums? hopefully use the good ones, I am getting ready to put my 318 reman motor in , swapped head gaskets to 028
 
They repair those that they can. I have seen weld repairs and plug type repairs. They work well if done right.
 
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