Ruredi,
Here is the ca18 sohc 8v Naps w/ the same features as the Z but smaller valves, ports and bores. Its a turbo ca18et thats putting out 443nm / 258kw atw @ 5500rpm using stock cam and done again by a Finnish dude.
He went aftermarket rods as prepped Det rods would be just a small saving. Stock mid throttle inlet manifold is restrictive compared to the later one. Head is stock also.
Not bad for Nappy head that I agree are crap if cast in australia like most ca20 are.
http://www.dnsf.org/forum/index.php?topic=32062.120http://www.dnsf.org/forum/index.php?topic=32062.0