Offsets - Clearance - best sizes to go for?

[GTvr]

I am looking to change the alloys on my car to 17" know the pcd is 108, its the offset that i find a little puzzling - I beleave original fronts are quoted as ET25-15x7 and rears ET35-16x7.5 would it be possible to fit alloys ET40 17x8 all round, if so what size spacers and tyres would i need and would there be clearance issues?

If these wheels will not fit can any body recommend the tollerences for 17" upgrades.

many thanks in advance.

[adavy]

i've got 17x7.5 et 33 allround with just a 3mm spacer on the fronts. no rubbing at all. i wouldn't touch 18s