Please guys, I bought this head over the weekend for R150 / around $20 and I need help Identifying it




















Note green shows no open gallery
Note yellow shows that it has round ports not oval like the gasket
Note the red crosses shows bolt holes on the gasket wich aren't used on the head
Note blue dotd indicate where a bolt comes from the head, but there isn't a hole in the gasket


I got this info from the wiki, but I'm still unsure:

These seemed to be the most relevant


A12T: (M08) Same as GX, but for Datsun Cherry

A14T: (M24) regular oval with dual springs

A14: (M49, H77) Oval Port, dry manifold, A14

Note that these are all marked with an M number, as is mine, M30

Oil passage in the head:

Top: 1974, no passage

Combustion Chamber:

A,B: Heart-shaped high-compression chamber is good for high-octane gasoline
a.k.a: closed chamber, peanut-shaped, butterfly-shaped or kidney-shaped

Intake Ports:

Round: These are best for low-RPM operation

Port Sizes:

Ports Size (mm) Exhaust Raised Note
round 28 27x26 no 1971 A12
round 28 ? lowered 1977 GFU

Valve Springs:

Single

Valve sizes:

Valves Intake PN (13201) In. Size Exhaust PN (13202) Ex. Size
A10, early A12, late A12 Van 13201-H1000 35mm 13202-18000 29mm
A12GX/A12T 13201-H2300 35mm 13202-H2300 29mm
Late A12, A13, A12AS 13201-H2300 35mm 13202-H7400 29mm

allthough when I measered them they seemed 1 or 2 mm smaller thsn thse, but these were the smalest listed

Coolant Passages:

Standard Datsun 1200 heads have no coolant holes on the intake side.

A10 head
The 1970 B10 is 9.0:1, same as the B110 ratio. Yet they use the exact same head. This indicates the B10 piston dish is 20% larger.

Intake valves: 35mm 13201-H1000
Exhaust valves: 29mm 13202-18000
(optional) Rally Springs (dual valve springs)
Round Ports
Dry manifold
Early heads have non-A12 fittings
Late A10 heads are same as A12
B10 Coupe with A10 engine had different part number. It is unknown how it differs from the regular Datsun 1000 cylinder head.

A12 Round-port Closed Chamber Head
All B110 JDM
H10, head not marked
USA to May 1971
Early 1971 model were fitted with Closed Chamber heads. Known in SCCA racing circles as the "H Production" head, legal alternative for A12 engine.
See discussion: Are these A series GX or comp heads? Experts needed!

http://datsun1200.com/modules/myalbum/photo.php?lid=15690

Some say a ported and polished standard A12 head with larger valves fitted flows about the same as a standard GX head. See head trivia.

A12 Low-Rise Round Port
Low-rise Round Port
G25 cast number
From late model B122 truck with A12 engine

* closed chamber, good type
* no oil passage meaning it is a 1974 or newer head
* round ports
* dry intake manifod
* original manifold bolt-pattern
* M30 casting mark

M30 is the best key. This means it was orginally designed for Nissan Cherry, probably later E10 or F10 model series. Because M22 is the latest listed in the wiki and that's 1973 E10.

I'd guess this is an A12 head from the late 1970s. Because 1980s moved to wet manifolds.

It's a good one for low-RPM usage (under 5,000 rpm) for an A12.

note second pic, the dammage to the chamber, some of the others also have, but that one is the worst, propably because of the broken valve clearly pictured.
How would this head compare to that of an a14, wich would be better for a hot street engine?
And what mods should I do to it, obviously bigger valves as these are tiny. I have an a14 in my 140Y and I want to give it more grunt, but I only have the one car,
so if the engine gets worked on I'm stuck without wheels, thus I bought this head, the guy said it was a GX head, but it is clearly not, but at least its an extra now,
Or should I try and get another head to have work done on? I know GX heads are nice, but they are also scarce, wich is the next best thing?
Also can any head be fitted with double valve springs?

Get a 1400 bakkie head. They have oval ports. You might just have to do something to up comp to 10:1 and also bigger valves.

Ek kan vir jou 'n GX ene kry, maar dit gaan R2,000 kos vir ene.
Ek weet dis baie, maar die ou by die scrapyard soek flippen baie vir hulle (ek dink hy het agtergekom hulle is skaars en mense soek hulle). Ek moet ook die head laat meet en preasure en crack test wat in daai prys ingesluit is.

Damn, does that include the rocker assembly and double valve springs?
What should the bakkie head cost?

I don't know what the bakkie head will cost.

The price is only the head complete with the valves and double valve springs, no rockers. My only concern is that I have never come across a head that the cylinder head shop told me the valves and valve springs can be re-used again. Maybe just my bad luck.

Are all a-series rocker assemblies interchangeable?

As far as I know, yes.

I think to up the comp you need thinner head gasket or head shave or change pistons. Correct me if I'm wrong, I dont mess with that stuff much.