Wheel spacers = mainly for show or to get wheels sitting flush with arches etc
It'll widen the track of the car by the amount you've spaced the wheel out by obviously
You can use spacers to allow other wheels to fit our cars (For example if you'd bought aftermarket Impreza alloys which would have an offset of ET52 I believe) if you fitted them along with 15mm spacers they'd then fit our cars without any issues
They MUST be hubcentric if not then they'll flop about whilst the wheels are rotating. Not such a massive issue on these as the cars use bolts not nuts but on most cars which use wheel studs it can cause undue stress on the studs as can using wheels without spigot rings
Disadvantages are the price
Very expensive in larger sizes (Anything from 80 quid upwards per axle)
Can cause issues if you go too large as you can sometimes put the wheels / tyres underneath the arches which can cause issues if you're lowered and you go over a bump the suspension travel can cause the arch to come down on top of the tyre and potentially cut into it and cause a blowout / puncture etc
My old MR2 when I got it. 8.5J ET36 DHS Alloys with 20mm spacers rear 15mm front
Mr2 when I'd finished sorting out the previous owners **** ups
It's probably one of the most discussed topics around so if you can't find information on it you're not looking hard enough
