Thinking about selling my A12 GX head. I need money for cert and not really planning on using it any time soon. Its been ported and skimmed (a lot). Would be good for a race car, however to run it on a road car on pump gas you will need a very aggressive camshaft. Standard valves, it had double valve springs but one of the inner springs on the doubles is broken so I would bin them. I can supply them with the head if need be.

I'm sure it is a genuine GX head, has no casting numbers, simply says 'NISSAN'. Has high oval ports, extra rocker oiling hole for early type A12, large water ports under inlet ports (blocked), 37mm and 29mm valves. A15 is 37mm and 30mm, A12GX are 35mm and 29mm.

Was originally on an A14 in a rally car, then a Lotus 7 replica (the guy i bought it off). I got the whole motor. He replaced it with a blacktop 4age but was disappointed that it was slower than with the a14.

He managed to cook it at some point (something to do with the radiator), and then said when he got the head skimmed it blew a head gasket again. Thats when i got it. Got a mate to get it checked out for me and turns out it wasn't straight. So I have just had it cleaned, straightened and a 5 thou skim. Also had pressure test, hardness test and crack test, these all came out fine.

Seats look fine but you might want to re lap them in. Ports are fairly large oval at 30x39mm (standard A15 is 28x34mm). Removed valve guide bosses etc. See the pictures. I don't know chamber volume sorry.

Want $400 for it. Head is in NZ, but shipping is cheap, looking at ~$40

Sorry for #OOPS# phone camera photos.

Cheers,
Rob

Those recesses from the head bolt washers around the head bolt holes are typically a good indication of the material hardness of the head, yours looks like it has had a fair amount of heat through it and that it might in fact be soft.

EDIT: I have just re-built mine and it's almost certainly on it's last legs. Same situation really, recesses around head bolt holes, pulled threads etc etc.

To run this on a road car you'd have to do some serious thinking about deep dish pistons or thick head shims, relying on a camshaft won't really help things along.

I thought my head was the most skimmed I had ever seen.... and now I've just seen yours.

I am interested in it;

Can you confirm chamber volume? They look to be around 18cc.

Are all the threads in tact?

Are you negotiable?

I have also sent you a PM.

Hardness was checked. Was all around 80 Rockwell hardness and dropped to 70 between 2 and 3. I was told by my engine re-conditioner that this would be fine and the general lower accepted limit for hardness is 55.

This was on a road car, running an 80degree Nismo race cam and ran pump gas (98 octane here). But i agree it suits a race car. I was going to run it on a road car using E85 ethanol blend fuel.

Threads are all fine, I have not pulled out the manifold studs though.

I will see if I can measure the chamber volume. Might take a few days though.

Cheers

Judging by the amount of material left around the thermostat housing it's getting close to what mine is.

That's why I'm running a steel shim plate.

BTW it is a GX head.

No one interested? Still in the process of getting a burette to measure chamber volume.

Still for sale.

CC'ing this week. Someone must be interested!!

Now is on Trademe

http://www.trademe.co.nz/Browse/Listing.aspx?id=307057063

chambers are 20cc which works out to be around 11:1 CR on standard dished pistons.

What are freight costs like to send to Victoria, Australia?

Valves and springs included in price?