Fellas,

I found out something pretty interesting about our site. Head over to ianspropergander blog auto technic pages to check it out, or look closely at the pic below. Cheers!

I hope you realised that there is a full page write-up of the AY12 Engine. Including diagrams.

Interesting stuff, what a treasure.

Also the even more rare, downdraft AZ12?

EDIT: How on earth did you find this article?

EDIT, EDIT: Holy #OOPS# is that your blog/page?! Lucky you.

Yes, sure is my blog. There's more in Pictures too, including a close up of the AY head diagrams.

You lucky bugger.

Absolutely fantastic. I have no idea how to navigate around wordpress, but I'm stoked to see the diagrams.

And the head is as simple as it seemed. The push-rods simply serve a rocker shaft that is offset from the standard. That was why the head was so wide. I wonder if the bolts along the cover are anything to do with the rocker pedestals.

Chris, it was a bloody brilliant trip. I'd definately reccommend at trip to Japan to anyone on here. I visited Endo San from B-Pro as well as Hirota. It's not that expensive either. If you look back through all the old posts in the blog you can follow the trip.

Here are some larger pics I just nabbed. Let me know if there's anything else you want.

Cheers

Well that page shows the engine fitted with a Cherrys alloy sump and the other pic shows the engine mounted in a cherry. Im sure I would love to let any one that had one of these fit it up to one of my Cherry's. Great stuff this

I'm pretty sure these were specific to the cherry's wombat. Especially going by the format of the extractors.

Ian this is excellent, I might get that page translated by one of my uni mates. I'd take that AZ any day over the AY. I had heard of another DOHC engine that had a very tall head but I had never come across concrete information on it. I wonder if it would fit under the bonnet? I suppose you'd drop the mounts.

Also looks like the AY12 ran an electric pump only.

You have also helped me establish what on earth my A series oil pump came off and it looks like is is the very same pump that is hanging off the AY12 engine. Brilliant!






You have to have a chuckle at the enormous dizzie.

In an attempt to condense some more info that has been seen before, into one fresh thread, here is my modest contribution.
As always, click on the images for a larger view.

This, clearly, is an original AY engine. With reference to the large distributor, it will be noted that it serves eight plugs, so these engines used two plugs per cylinder.
The original design & prototype head [& engine] used only one plug per cylinder but production[?] heads used two.



















This well known & over used image shows an AY in a rear drive car. Note that it is using a 'standard' competition oil pump. I suspect that the pump in the previous illustration uses a special cover on the comp. pump to allow use in a front drive car.
















As can be seen from this image, the studs that secure the rocker cover, also secure the rocker pedestals.
There are four unidentified objects along the aproximate centerline of this head & I speculate that these are the four additional spark plugs that these engines used.
The new production heads that are being developed will revert to the original single plug design.


























As for the AZ engine, I suspect that it never got beyond the design proposal stage as we have never seen reference to it anywhere else but it would be wonderful if one or more were actually made.
I wonder of they used a short cam section in the block to drive the oil pump & distributor, & I wonder what the drive to the overhead cams looked like.

EDIT
The AZ also seems to be a 'dry sump' design so I wonder how the scavenge pump was to be driven & what is the object depicted in the position where the distributor would normally go.

so those ay heads are still going ahead dodgeman??