My old golf had coilovers on it, and I couldnt lower it because the wheels were too wide, and before I could figure it out, I sold the car to upgrade to mk5, ive thought about spacers but my wheels already fit flush with the body, any other ideas, please let me know, any feedback would be great 
Few things you could try/consider....and all depends on what look your going for!
A smaller J wheel would naturally sit closer in, for example a 8.5J wheel sits flush, whilst a 8J wheel sits slightly closer in and will probably allow you to go lower.
Stretched tyres can help create space to go lower. Depending on what wheels you have can also have an impact. For example, wheels with lips that protrude from the arch will act as a natural blocker, whislt 'flat' wheels won't. Depends on how low you wanna go for this to really matter.
Arch rolling I guess though is a catch all solution and will give you some more space to go low. Your wheels may not be 100% flush but that 1mm difference could be all you need.
Spacers, will push you wheels out and give you a lower offset so won't help you trying to get low, but a higher offset wheel may well do!
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