Everybody with a modded impreza should have one of these.
 

Group buy on the Phormula KS3 Knock analyser.

This is essentially a much more sophisticated knock link. Its a much nicer display and can be used for mapping. This will instantly show you if you engine ever dets with both a visual and audiable warning.

Get one whilst theyre cheap... these are a stunning bit of kit.

https://www.scoobynet.com/group-buys...knock-pro.html

Sorry mate, I'm gonna show my ignorance, but what does it 'do'??

(In laymans terms please ;) )

Its a digital knock sensor and will show you youre engine, knocking, detting, pinking, pinging.

It gives you the chance to take youre foot off the gas before you blow it sky high.

Ta :)