Have a look thru some of the k10 blogs
Not much in the way of 'off the shelf' items, everything is custom made
Bike carbs are a decent power upgrade, cheap if you can fabricate the manifold ur self.
Heads, give it a skim, how much? Not sure, Dw engineering has a load of options and prices on there website
Exhaust, custom made
suspension, lowering springs or modify polo 6n coilivers
Basically you have to make everything
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