230+ Kw @TW is alot of money. That's 400HP @ flywheel. Think about what you are asking from the motor realistically. I'll give you one of Morrows secrets for free. His is a L18, still a 1.8L. Not because he is cheap but because it works. Combinations sound great on paper and are great to tell your mates this or that but it is all wank when you introduce a turbo. The megre gains of combinations are trivial to a street car in my opinion, and this is not just my opinion, but the handed down opinion of thousands of HP hunters. The blokes who need to get the extra power have maxxed out their race car and are searching for every extra Kw they can find.

Remember the KISS rule. Keep It Simple Stupid.

Here's another free Morrow engine tip. After a few different camshafts, Nizpro found they could get more power from a standard Z18 Turbo camshaft. It's all in the turbo choice. And bigger is not better. A good T25/28 Ball bearing turbo will spool up nice and fast and give a good power range.

And as Stu has pointed out, there's good gains in the exhaust manifold. Choose the right bits, based on what makes a good combination, not what some d!ckhead down the pub tells you what is the shazizzle.