I think they might be around 2" spacers.
175 size will be too wide for a Zen.
My best bet would be 165 width tyres
i totally agree with you, even as of now i have 165. but im using an e-zen so thought the 175 can give more grip, and besides will the stock esteem rims be able to hold the 175 tyres properly ? because by monday or tue i plan to change to stock tims n 165 or 175 g3 ( provided the stock steel rims can hold the tyres properly )