Hello. I am another newbie, although I have been lurking on this site for many months now. I have a '59 Austin-Healey Sprite (Bugeye/Frogeye) with an '82 A15 powertrain.....a similar set-up as 'RickB's MG Midget (although mine has the twin Hitachi SU's).

Anyway, my question is how can I tell if I have the "performance" head? I have a receipt from the PO showing a valve job being done to a "Nissan Performance head", but I have no clue if it is on the car or not.

Here's what I know......it has double springs and is an oval port. I will include a couple of pictures......maybe they will help. I cannot find any stamped numbers or castings of any sort that would help identify the head. Any help would be appreciated (just want to know if it is stock or better than stock).

Also, what valve/rocker cover gaskets are you guys using? I used Fel-Pro brand because they always seemed to be the best, but it's only a few months olds and it leaks. I found a different brand but it is made from cork and is 3 times more expensive! Is cork preferred over the rubber or ?? Any brand preference?

Thanks again.

Mike

Looks to me like a gx head. These are the best production head for the A series. The oval ports are slightly taller than the standard oval A14/A15 ports, to match up to the SU manifolds. You will also see large (8mmish) water gallery holes underneath the intake ports. The Standard A15 (H89) head has much smaller galleries here. These heads have smaller valves that the A14/15 heads. Although it's not a huge job to have a shop recut the seats to accept the bigger valves if you can track some down. These heads had dual valvesprings from the factory, but these aren't a high perfomance spring.

The stock GX head works well , I use one on my 1200 road race car. The A14 valves will fit pretty easily. The GX motor will rev to 7800 RPM's all day long.......if say you were surrounded by a bunch of loud Roatary cars and couldn't hear the engine AND were busy looking for the green flag to fly.............I've heard rumor that they'll go to 8100 RPM's and finally float the valves but since its a non intyerferance fit engine I got.......I mean I heard you can get away with it.
The Fel-Pro kits are good , I'm using and re-using and re-using the cork valve cover gasket and it doesn't leak.

Tom

Thanks! That's what I needed to know. I guess I won't know what valves it has until I tear things down for a rebuild, but that won't be anytime soon. It's possible that the PO cut in the bigger valves when he did the valve job that I have the receipt for.

My tach is a bit off, so I don't know how high I've revved it , but every once in awhile I let her scream! It certainly feels & sounds like 8000 RPM's!

I'll try the cork valve cover gasket, I guess. The one I got from Fel-Pro was rubber, but was cheap looking and obviously leaks. There is no difference in gaskets between a stock head and a GX, is there? I'm pretty sure that's a no, but may as well ask.

While we're on the subject, is there any aftermarket aluminum valve cover (or something that looks better than the stock one) for the A series engines?

Yes, there are a few aluminium rocker covers available for these engines. Do a search and you should find them. The rocker cover gasket is the same for all A series nissans, BUT, the GX manifold gasket is different due to the taller ports. I don't know if they are still available off the shelf.

The excitement is rising.
OK, firstly there are three different GX heads that I know of, that being, ...
1200GX with the 1200's rocker oiling gallery
A12GX. Basically a slightly modified 1200GX head without the 1200's oil gallery drillings
A14GX. As far as I can tell, these are based on the production A14 oval port head with dual valve springs.

I see NOTHING in these two pictures that would indicate one way or another just what we have here other than an oval port A series head with double springs.

If we can get some more pictures of the engine, particularly the induction system & the Hitachi carbs. [Is saying 'Hitachi SU' the same as saying 'Holley Carter'?]
The carbs were different for the three different GX engines & may shed a clue as to what we have here.

OK.....you can almost see the induction system on the bottom of the first picture, but I will post something better shortly. By 'Hitachi SU', I mean they are twin SU style carbs built by Hitachi (flat tops). The intake manifold is custom, so you won't glean anything from it, however, I have the stock manifold that attaches twin SU's to the A15 head (it is the one I am thinking of selling to 'RickB' for his MG).

Like I said, I have no idea how to identify what head I have. The only thing I have to go by is a receipt for a valve job done to a 'Nissan Motorsports GX head'---this is what is written on the receipt. It is dated May 1998 and I bought the car in July 2006, so it is very likely to be the same head, but you never know.....he may have removed it at some point or it never was a GX head to begin with.

I believe he ordered this head through the NISMO catalog.....I have found "wish lists" for a GX head in the paperwork I got with the car, but no official receipt for the head itself (just the valve job). I don't know if he ever bought one from NISMO or got a used head somewhere.

Here are some pics.....the previous owner made his own intake manifolds as well as air induction set-up. I will be installing more traditional air cleaner assemblies as soon as I can find something.

Thanks for the pictures.

The manifold & carbs look to be 120Y type [B210] & it's even possible that a complete used head & induction was bought.

Below the intake ports of the manifold is a horizontal slot. This is ti receive the coolant from the head which passes under the runners for the purpose of heating them.

The head, if it is an A12 GX unit, will have two holes of about 5 or 6mm diameter under each pair if intake ports. These are to supply heated coolant to the manifold & there are four holes in total.

These holes are unique to the 1200 & A12 GX heads. As for the A14 GX head, well of that I can't be sure. They may have the four holes, but stock A14/15 heads have only three holes [the front one is not drilled] & they are much smaller. An A14 GX head would of course have the 37/30mm valve sizes while 1200 & A12 GX heads have 35/29mm valve sizes from new.

I wonder why he went to all the trouble of fabricating a manifold when the original would be just as good if not better.

Thanks for the info.....much appreciated. I will have to take the intake off at some point to see what the head looks like (but not anytime soon).

I wondered why he would build his own intake as well and the only thing that makes sense is clearance issues. It's possible that with the stock manifold the carbs might hit the hood.....not sure though.

I base my belief that this is a GX head on the basis that it has no "H" number on it. That, and from what is shown in the picture it resemble my GX head which has the small chambers, bigger H2O galleries, (Four of) and the taller ports.

Something you said has made a penny drop though Chris. You mention the B210 GX head. That is what our friend here and myself must have. The B110 GX head had an "H" number did it not? The head we see here does not. Also, Mine already had the correct oil gallery drilling for the later model block. (Post B110, dizzy in the midlde) So this May explain what head these are. WhoYourDatty1200 has one of these heads too.