Okay mate there are a couple of us who dream about a low pressure turbo conversion for the 1.4spi. (If a company came up with the goods I reckon they would make a mint)
But there are some real issues to resolve before it would be possible. Dont get me wrong, Im sure with enought time, money and effort thrown at it, it could be done. It just never has been before as far as I know.
Here are just a couple of problems:
Compression ratio = too high
Single injector is crap
Need custom inlet and exhaust manifolds made
Need beefed up ECU, possibly a remapable jobbie?
There are lots of other things as well which I cant think of right now.