boyed\ up

To make something (especially a tart box) look even tackier than usual in pursuit of transient performance benefits.

Boyed up cars (usually Vauxhall Corsi in the UK) are used to cruise slowly down the high street of towns in the UK. Sound track usually provided by ridiculously large stereo playing something loud and thumpy.

Typical boying up ploys include: fat exhaust pipe (limiting performance to less than 50 mph), go-faster stripes, whale tail wings for extra down force at speed in excess of Vauxhall Corsa capabilities, fluffy dice, resprays.

Darren had boyed up his mum's Corsa for the night by sticking bin liners over the inside windows, giving the effect of smoked glass. Unfortunately, it also caused him to back into a lamp post.