Why not just do it the easy way and either: 1: buy a Sapphire Cosworth, or 2: use the 24v version of the Cologne which has 200+ bhp as it is, or... well I dunno but it seems like you're making work for yourself.

And regarding your last post I don't think there was a 16v Sierra that wasn't a Cossie, unless you mean the twin-cam 2.0 which is in fact 8v??