Thanks for the suggestion Peter, but Heinz is absolutely right. I did do quite a bit of research into a blower early on in my tenure, including having a long to to a guy at Cosworth, and the general advice was that it just is not worth the trouble and expense. It would probably end up costing the same as Griffos conversion once all the extra bits and pieces plus work in getting it all to function have been added.
The answer is to forget torque and buzz along in one gear lower than normal. As it happens after 7000 odd miles, it seems to be getting torquier in the low and mid range, but nowhere near what a modern Ecotec engine is giving.