How to tell which head I have?

[Locke]

Thanks for the help everyone. I stopped by the shop and got to take a look at the head. It is an E31 as I suspected. The machinists showed me some cracks and even where some of the ports on the underside have been chipped due to corrosion -- and reaffirmed that they cannot salvage it. I'll take some pictures if anyone is interested. So, in the mean time, does anyone have any tips on where to find an E31 for sale? They seem to be rare.

[240260280]

Cams are tough. I rescued this one and it is in my 77:

 

 

 

[Patcon]

56 minutes ago, Locke said:

Thanks for the help everyone. I stopped by the shop and got to take a look at the head. It is an E31 as I suspected. The machinists showed me some cracks and even where some of the ports on the underside have been chipped due to corrosion -- and reaffirmed that they cannot salvage it. I'll take some pictures if anyone is interested. So, in the mean time, does anyone have any tips on where to find an E31 for sale? They seem to be rare.

Would love to see pics! We like pics

[240260280]

Maxima N47 is a nice upgrade for a 240z engine.  @madkaw has one for sale.

Or you could grind an E88 stamp to read E33 and tell people it is a rare racing head.

 

 

[madkaw]

1 hour ago, Locke said:

Thanks for the help everyone. I stopped by the shop and got to take a look at the head. It is an E31 as I suspected. The machinists showed me some cracks and even where some of the ports on the underside have been chipped due to corrosion -- and reaffirmed that they cannot salvage it. I'll take some pictures if anyone is interested. So, in the mean time, does anyone have any tips on where to find an E31 for sale? They seem to be rare.

They are are rare because a lot of them didn’t survive. Not the best castings at first and normal wear and tear , and normal neglect has dwindled the numbers . Some were damaged because the seats fell out because it was an inferior design flaw. Electrolysis is usually the worst offender .My 9/71 has the e/88 which is the same exact head( early version only) as the 31. 

Just depends on what your plans are for the car. 31 heads pop up every once in a while, but look carefully. You could get another head on there to get the engine running while you look for a 31 head. Or just put a complete engine in there while you put back together an original engine package

[Captain Obvious]

3 hours ago, 240260280 said:

Cams are tough. I rescued this one and it is in my 77:

Yeah, and look what it did... Rust is seeping out of the hood vents!!

More pics here: 
https://www.classiczcars.com/forums/topic/60218-ol-blue-current-status/

 

[240260280]

1. Not for long "Sandy" ?

[Locke]

Sorry for the delayed response. Here are a couple pics showing some of the damage.

[Patcon]

Looks like detonantion damage in the combustion chambers. I wonder if that's what cracked the head. The crack and the detonation damage sort of does the head in. I don't even know if the crack could be fixed. The detonation  damage and the coolant passage erosion could be, but would take lots of work. I would say that's done. I don't know if I've ever seen a head in that bad of shape that wasn't off a turbo car

[Locke]

2 hours ago, Patcon said:

Looks like detonantion damage in the combustion chambers. I wonder if that's what cracked the head. The crack and the detonation damage sort of does the head in. I don't even know if the crack could be fixed. The detonation  damage and the coolant passage erosion could be, but would take lots of work. I would say that's done. I don't know if I've ever seen a head in that bad of shape that wasn't off a turbo car

Yeah, I knew that the car had sat for nearly two decades and the seller said there was likely a blown head gasket but I never expected this kind of damage. Oh well. I've got a pretty clean N47 head that I may temporarily put on if I cannot find another E31 anytime soon.

[Patcon]

3 hours ago, Locke said:

Yeah, I knew that the car had sat for nearly two decades and the seller said there was likely a blown head gasket but I never expected this kind of damage. Oh well. I've got a pretty clean N47 head that I may temporarily put on if I cannot find another E31 anytime soon.

Yeah, it's unfortunate. I haven't really seen that kind of cracking on street engines that haven't been severely overheated. It's good you have another option. How do the chamber sizes compare?

[Zed Head]

A hard freeze could probably do that.  "Freeze" plugs aren't really there for freeze protection.