hey,
i was reading another thread about ports on what. and ive got an a15, but its got round ports on it. do i have a different head? its got a black valve cover haha.

a15 never came with round ports

i'd change head as soon as possible that motor is breathing through a straw!

most likely an a12 head has been put on, some a14 came with round port but thats quite rare

oval port is definite upgrade

If you click on the tech section and follow the engine / cylinder head links untill you come to a list of different head types you will find that there is a round port head that came off an A12/A14 which is drilled to the same pattern as the oval port heads.
http://wiki.datsun1200.com/index.php/A-series_Cylinder_Heads
It also gives you casting numbers to identify it.

im pretty sure the round port interchangable head comes from vannettes

Quote:
All A10, 1200 & A12 round port heads used a single manifold stud between the pairs of inlet ports. This is the most common round port type that will be encountered in Australia.

There are some round port heads that will rarely be encountered that were used on the A14 'thrift' engine. These used two studs at about the 11 o'clock & 1 o'clock positions at each pair of inlet ports. This is the manifold stud pattern that is normally associated with oval port heads.
This head was NEVER fitted on an A12 engine from the factory.