Urban Legend
Sorry, guys. There are only TWO heads with four valves that fitted to the L-Series block PERIOD.
One was available from O.S. Gikken in Japan, and is around (or was) $24,000. When compared to a properly-ported non-crossflow head, it was not competetive.
One was a prototype, never completed. Theis was the "Paeco-Goertz" Casted head. It recently surfaced at a Swap Meet in SanDiego, and was purchased, along with tooling and blueprints by a gent living in SoCal. Not me, I'm sad to say...
The Nissan Crossflow head had about 5% more HP than stock non-crossflow. Far from the "200HP" Benchracing figure claimed above. This advantage carried all the way through including porting so at terminal development, it would produce about 5% more than a similarly-prepared non-crossflow head.
As for the S-20 engine (used in the Fairlady 432 and Skyline GTR from 69-73) it was a totally different block, and not compatible with the L-Series. It was dropped after Nissan realized they DIDN'T NEED A DOHC to make the power to be competetive.
Any current DOHC engines are most likely from the RB-Series engines, a development and next generation of the L-Block. Not compatible.
I mean, you can make anything fit on anything else, but why?
Check the archives, there's this info posted over and over, and over...
