Pendles

Hi there.
I am in the process of building a little performance A12.
My A12 engine has the GX head on it that I do not want to use as they are very scarse to find.
I went a few weeks back to the place that sells Japenese imported engines here.
I got hold of a A15 head that also had the H89 marking on it and I think I am going to buy one and use it for the following reasons:

1. It has the same oval ports as my GX head.
I also looked inside the ports and could not find any swirl flow blockages that can make flow slower.
2. When I looked at the combustion chamber, it also had a heart shaped chamber like my GX head.This gives 10:1 comp.

I think this is the closest head to the GX that I can find and you have this head, I think.
I would go with the head and the SU's.
see how they work.
If they do not work very nice then try something else.
They are great for fuel economy.