There is the oil-passage question. The A12 has oil come up by the thin bolt. Not sure if the heads have the same oil paths. This was discussed authoratatively in the forum here some time ago -- Search should list it.

But aside from that, while you'd get more compression, good for more torque, the ports are smaller with the A12 head ... so HP would be limited. Better to work/port/polish the A14 head. Increase compression by milling the head (or put flatter-top pistons in).

Isn't there also an issue with one of the head bolts? Something about how the rocker assembly gets its oil? I think they will NOT interchange, but I don't know for sure.

i believe this is the case also due to diffrent shape combustion chambers,
im not sure if your asking this question or not but all heads, exhaust and inlets are interchangeable, except for the fact you may have to close off watergalleries on some inlet manifolds for some heads, im buggered if i can remember which though

im not to sure but i hurd that the a12 head would give more compression on a a14. ill ask arround and get back to you.

akssmith@iprimus.com.au

Hi, wondering whether A series cylinder heads are any different?

ie would a worked/port/polished A12 (originally) cyl head be fine for an A14...

Apart fom the exhaust manifold as Im getting custom extractors...
And the inlet manifold which I have for A12 and A14...

So I have the offer to by the worked A12 cyl head will it be fine for the A14??

Simon