P90 Cracked in 3 places repairable or not?

[ArchetypeDatsun]

So I'm rebuilding my L28ET from 83 280zx turbo, and my P90A hydraulic head was in really bad shape. I aquarred a 81 L28ET 3 years ago that had been rebuild a few years before I got it, but it was in a garage fire from what I was told when I got it because it was super dirty. I tore the 81 turbo engine apart and the inside the block was super clean and the head looked really dry with oil residue. I took the P90 off the 81 L28ET to the machine shop and I was called the next day only to be told it was no good. They told me it wouldn't hold pressure and they found 3 cracks on the bottom the crease between where the 2 valves meet. So has anyone else had a cracked head before and if so are they repairable or are they just junk now?

 

Here's the cracks one on front where piston #1, then #4 and #6

Edited May 6, 2012 by 280zx@541

[BluDestiny]

Probably possible with chamber welding, but if your going to spend that much just try to find a new head.

[ArchetypeDatsun]

Probably possible with chamber welding, but if your going to spend that much just try to find a new head.

 

I was told the same by a friend that works at Nissan, I have that P90a still but the hydraulic lifters are bad but I was researching on here and saw how to convert it to solid lifter and I watched Big Phil's YouTube video. I also have a P79 I was thinking of taking the "A" camshaft and lifters off that and putting on the P90a.

[BluDestiny]

That would be a better solution and make a slightly more aggressive head

[ArchetypeDatsun]

Yeah from what I have read it does I'm only planning on keeping it a DD for awhile so it should make a fun driver. There's still a lot I have to do to the car since its a ongoing work in progress.