Which head to rebuild? (huge pics inside)

[Mr. Y]

Hi guys!
I'm going to build spare head that will be used in my next rebuild... So I have two JDM heads and trying to figure out, what to build.

I'll post damages, please comment them. And then - put your opinion what to build, please.

Head number one (casting #3):

1) Block-mating surface is scratched. Scratches aren't too deep (I think 0.1mm or less):


2) in one cylinder squish pad is damaged during transportation:


3) Some minor issues (broken stud)...
I've disassembled one exhaust valve in cyl #6 and it almost has no freeplay. So valve guides should be good.

Head #2 (casting #7):
1) Deep score on one cam cap:


2) Unknown side damage:


3) Big freeplay in valve guides (checked on one exhaust valve in cyl #6)
Head #2 has no damages in combustion chambers and surface is not scratched at all.

So, what do you think?
I'm going to do this:
- oversized valves (2JZ)
- light porting (haven't flowbench, so removing a lot of material is too scary for me)
- replace exhaust manifold studs
- resurface
- comp cam valve springs

As for other setup: Eagle rods, Probe pistons, MHG, ARP, FFIM, BIG turbo (67mm or more) and rev up to 7500 (Standalone)...
My goal is: maximum HP on pump (@14 psi)... and a little more on pump+meth injection (@23 psi) =)

And one more question: what do you think, for my setup and goal, worth it to install 2JZ valves? (it will cost about $500) I can't afford aftermarket +1mm valves... so stick with stock or JZ route...

Thanks in advance for advices!

 

[jdub]

I'd have the 1st head hardness tested to make sure it's not annealed...also make sure its not warped (max is .10mm or .0039"). If good, use it. The small damage in the compustion chamber area you showed can be smoothed out easily. The scratches you showed "look" like they will come out when decked...hard to tell though.

The damage to the cam cradle on the 2nd head would be harder to fix (if it could even be done) and a lot more expensive for the line hone required.

 

[NewWestSupras]

I'd do a hardness test on both, and ensure they aren't warped. Go from there, they both look useable, if above is good. I kept my head with stock valves, did my own port and polish, and used Compcams valve springs. It seems to flow just fine. I'm not sure if the added expense is warranted for new valves, but I'm sure more knowledgeable members can help with that. Gl.

 

[Mr. Y]

thanks, 1st head looks more usable to mee too.
As for hardness test... Sorry, but our "machine shops" do not know what is it (along with many other things).

 

[jdub]

Unfortunately, if the head is annealed (soft), that makes it useless