From here it also looks like it has double valve springs, thus rendering it a GX head as no other A series heads had them.... Im with greg on that, GX also had the NISSAN casted on top and no other had this lettering on there

yes it as double valve springs.

here is one link of the head

this could be a nissan competition head????

head big photos

The nissan comp heads have like lumps betwee the head bolts and the wee bits above the manifold studs, overtop of the intake ports. I think it must be more material to allow for even higher porting.
I agree that this is a GX head.

And the A15 head? could be like this?

Be careful, many standard heads have been fitted with dual valve springs. So having dual springs doesn't make it a GX head, but is one indicator.

DatsunSSS, A14 and A15 heads are the same, but are not GX heads, which come from 1971-1973 B110 GX cars.

thanks for the help, but what you think of my a12 head?

!-dont have the cating number, only have the nissan casting"

2-oval ports

3-double valve springs

4-big water holes

That comes from that Belgian rallycross car you mailed us about some time ago doesn't it?Sorry I couldn't be of any help,I didn't find any information about someone racing here in rallycross with a B110.That must have been a long time ago.......I can only tell you that the heads I use for racing are the same as yours,with the same markings 'nissan japan',and I am quite certain mine are GX heads.Here in Belgium we only got A14 engines from the B310 sunnys and N10 cherrys,and not many A15's.You also said that car had LSD and a close ratio gearbox,so I think someone back then spent a lot of money building a very nice car with very good parts,probably bought from people like Janspeed in England or Armbrust in Germany,these were the most common sources for race parts here.I wouldn't be at all surprised if that block had been bored to 76.8mm to give 1298cc.Have you dismantled that engine ?

i agree with you.

but i didnt opend the engine yet.

Having seen the larger pictures this is 100% A12GX.Nissan cast in head is a possitive.Oval ports,double springs,and large water holes are also found on A15&A14 heads.The head studs cast with the number 13 is another giveaway.GREG

The gasket is a14 or a15 cos they have a smaller size oval port than the a12gx
If the ports are the same size as the gasket, then it is prolly a a14. The a14 and a15 engines have three small holes under the inlets. two at one end and one at the other pair of ports. The a12gx head has four larger water holes under the ports.
The head bolts with the number 13 were used on a12gx engines and all a14 and a15 engines as far as i know. The best way to tell is to take it off and clean it right up so we can see all of it without any gunk or gaskets
I reckon its a a14 or a15 head.

and about now? is it gx or not???
and why the pulley is different?

one more thing!!

what is the best way , or product t clean the head? to make it shine as new

Quote:

acid bath? Any head shop should be able to clean it up fairly cheap. Probably cheaper than buying the products to do it yourself...

Ok that is the same head I got from nissan comp it is an a12gx head. appears to have been ported some and possible larger valves, looks like there almost touching. one thing to note it has the oil passage hole same as a12 that later engines did not

the timing gear has been modified to adjust cam timing during set up definatly not a stock engine

In my view, this is a Datsun 1200 GX cylinder head.
I have avoided saying that it is an A12 head as this would then cover the head used on the revised engines in the B210 GX from '74 onwards & the presence of the oil hole on the gasket face rules out these later engines, so Datsun 1200 it is.

I think the same, a12gx and yes as been ported, about 2 mm each side.


The engine have flat top pistons.

Must be a transformation, isnt it?


thanks to all