306 1.8 xs tuning ??

[Midnightclub]

You can't just fit the head, it'd need mapping to, but your ECU can't be mapped, so you'd need to go aftermarket... and so the costs mount up quickly.

If you can't afford to insure a GTi, I highly doubt you can afford to insure a declared modified 1.8 honestly (Unless you're planning on not declaring that is....)