I am going to be designing and manufacturing an ITB setup for myself for a K20. I plan on buying an entire EP3 down the line to use its engine, however until then I'll be buying bits and piece for the parts I plan to design and develop. I've seen a K20A6 cylinder head for sale for a good price and can't seem to find out for sure if the ports would be identical to the A2 or not. Rather than spending a lot of money on a head I won't need, I would much rather go down this route if the results will be the same. On the subject of K20 heads, what thread pitch are the inlet manifold studs too? Thanks guys.