I have been thru a pile of magnum heads over the years that I've dismantled hoping to overhaul and more have been cracked than not.
And though I've seen lots of post on the forums saying "run em, the cracks are superficial and won't hurt anything" the machine shop won't touch them.
I've bought the EQ heads and have had mixed results. The first time I bought them bare and assembled them with parts scrounged from the cracked heads I dismantled. That set still is on an LA 318 that I converted to run magnum heads.
Nobody touched the bottom end, which is still stone stock from 1983 except for a mild cam swap. That lower end is now well over 200k. Still running strong. I sold the truck with that engine in it to my cousin, my son bought the truck back from him just for that engine which is now in a 72 fury wagon.
Then, based on my experience with my first set of these EQ heads my son bought a set of ready to run out of the box ones, for an LA360 the he did the magnum head conversion on, and within 6000 miles it was apart and made into a 408. Reason for that was that it burned oil from day 1 after he rebuilt that 360 bottom end.
This was a freshly rebuilt, everything went thru the machine shop and everything.
When he sent it all to the machine shop to be made into a 408 they said they had to do some work on the heads, I don't remember what exactly. But it seemed they weren't right, from the get go. (As I remember, it's been a few years)
Then I bought a set of EQ heads for my wife's Durango. Since my first set this was about 8 years later. They didn't get 6 miles and stuck a couple of valves. Again taken out of the box and bolted on. Bent #4 exhaust valve in the process. Machine shop said they've had heads that sat in the weather for 20 years that weren't as hard to remove as these were. Another set of "ready to run out of the box" that weren't.
Well yesterday I was at the first swap meet of the year and a guy had a single stock factory magnum head brand new, never been assembled, never been on an engine for not much more than scrap price. It came home with me.
I'm looking for a mate to it.
I have a possibility sitting here, I think I still have 1 used one that came back "not" cracked from back when I had the Durango engine apart.
Would it hurt to pair up this used head with the new one I got yesterday? Same casting number.
I'm not looking to race it, though I might do some towing with it depending on what I decide to drop these heads onto. I have a couple each 318 and 360 magnum core short blocks here.
Whether I find another NOS head or whether I pair it up with that used one I have here, I do plan on doing some light cleanup with the die grinder before I put them together, nothing crazy.
And though I've seen lots of post on the forums saying "run em, the cracks are superficial and won't hurt anything" the machine shop won't touch them.
I've bought the EQ heads and have had mixed results. The first time I bought them bare and assembled them with parts scrounged from the cracked heads I dismantled. That set still is on an LA 318 that I converted to run magnum heads.
Nobody touched the bottom end, which is still stone stock from 1983 except for a mild cam swap. That lower end is now well over 200k. Still running strong. I sold the truck with that engine in it to my cousin, my son bought the truck back from him just for that engine which is now in a 72 fury wagon.
Then, based on my experience with my first set of these EQ heads my son bought a set of ready to run out of the box ones, for an LA360 the he did the magnum head conversion on, and within 6000 miles it was apart and made into a 408. Reason for that was that it burned oil from day 1 after he rebuilt that 360 bottom end.
This was a freshly rebuilt, everything went thru the machine shop and everything.
When he sent it all to the machine shop to be made into a 408 they said they had to do some work on the heads, I don't remember what exactly. But it seemed they weren't right, from the get go. (As I remember, it's been a few years)
Then I bought a set of EQ heads for my wife's Durango. Since my first set this was about 8 years later. They didn't get 6 miles and stuck a couple of valves. Again taken out of the box and bolted on. Bent #4 exhaust valve in the process. Machine shop said they've had heads that sat in the weather for 20 years that weren't as hard to remove as these were. Another set of "ready to run out of the box" that weren't.
Well yesterday I was at the first swap meet of the year and a guy had a single stock factory magnum head brand new, never been assembled, never been on an engine for not much more than scrap price. It came home with me.
I'm looking for a mate to it.
I have a possibility sitting here, I think I still have 1 used one that came back "not" cracked from back when I had the Durango engine apart.
Would it hurt to pair up this used head with the new one I got yesterday? Same casting number.
I'm not looking to race it, though I might do some towing with it depending on what I decide to drop these heads onto. I have a couple each 318 and 360 magnum core short blocks here.
Whether I find another NOS head or whether I pair it up with that used one I have here, I do plan on doing some light cleanup with the die grinder before I put them together, nothing crazy.
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