WTB: Naps Z cyl head

[Eagle_Adam]

title says it all, my brother seems to have blown the HG on his 4x4 and he ran it without coolant so im going to assume he warped the head too, at least i want to be prepared for that

WTB a good(flat) Naps Z cyl head

[wayno]

title says it all, my brother seems to have blown the HG on his 4x4 and he ran it without coolant so im going to assume he warped the head too, at least i want to be prepared for that

WTB a good(flat) Naps Z cyl head

Are they all the same, Z20/22/24?
Are you looking for a good usable one, or a core?

[izzo]

idk about the z20 but the 22 and 24 are.

Sucks he blew the HG.... Previous owner just replaced it (previous to me, not me )

[wayno]

I have a Z22E head, I bought a Z22E engine to make my LZ23 for the work truck, it just happened to be an E engine, but I will tell you this, that guy said it ran when pulled, bullshit it ran, #4 piston was so lose in the hole, I doubt it had any compression at all, so it is a well used head, which likely needs rebuilt, which he could likely rebuild his also, so that is why I was asking about the condition wanted.
I had not thought about it till just now, are the fuel injection heads different than the carb heads.

[RedBanner]

I got him.set up. Got 2 z20 heads and they are the same from all the info I can find. Not doing me any good lololol

[RedBanner]

As far as I can tell the fuel injection and throttle.body heads are the same. The 720 is throttle body right?

[RedBanner]

Ok I.stand corrected. Some z20s heads have a 12cc smaller chamber... thats a big difference. But the 4 plug heads may also have a smaller combustion chamber.... alot of weird non confirmed info on the z motors it seems like. So many changes in so few years.

[GreaseMonky]

My experience are that multi port, injection heads are diff from TBI and carb heads, and 20 is diff then22 and 24

[flatcat19]

Have you tried talking him into a L head at all?

[RedBanner]

He should lol.

[datsunmike]

Here's my take on the NAPS heads

I have two Z20E 4 plug heads from an '80 S110 200sx (all Calf. and all '81 Z20Es were 4 plug)
I have two Z22 (S) heads from 720 trucks.

Both of these are identical in every way except the Z22 has dual plugs. The Z22 even has the injector notches and both are 57cc combustion chamber.

I also have at least two Z24 heads. These are dual plugs of course and the same 57cc combustion chambers. But the intake ports are square with rounded corners while the Z20 and Z22 are round.


These heads are upside down but the top one is a Z24 (I made the injector notches) the bottom is either a Z20 or Z22 with round ports.


The intakes are also round or square and the same bolt pattern so, while not perfect, you could intermix them.


Now having said all this there is one other Z series head (already mentioned) that is about 12cc's smaller. I haven't seen one but I do have a picture of it. You'll notice a slight flattening of the left and right sides of the combustion chambers forming a small quench area....



Here is my Z24 head I was porting...




The small chamber head was used only on the Z20(S) 720 truck and possibly the US '80-'81 HL510 (A10)

I suspect, and it would make sense if, the small chamber head was also used on the Z18ET motor. 1.8 liters into a 57cc head would require pop up or domed pistons to bring the compression up any where near normal.

[MicroMachinery]

Still looking? I have one.