I have done a lot of research on 15's for a Sei by using the "search" function.
I saved the following comments:

"those very wheels would go straight on a cento with 10mm spacers and 195/45/15 tyres. in fact, 16's would go straight on a sei with standard shocks and springs"

"get 175/50 tyres for 15s.. they are thinner and so will not foul the arches and they are also the same profile"

"6 inch wide wheels maybe the best to avoid doing arm or arch work"

"The answer to fitting 15s on a cinq or a sei is simply the tyres. Solution. Use 175/50 tyres. smaller rolling radius and less drag. plus they are 2cm thinner so fit the arches! there quite readily avaliable too.



So, I wonder, has anyone actually managed to go out and buy a set of 15's with tyres, and fit them either with spacers with no modifications at all?

just to add that frrom recent posts and advice ones that fit a cinq may not be the same for a sei as the rear arches are not flared on the sei's like the cinqs.
TBH with mine on a 6.5J 15" wheel the rears need spacers to bring them away from he inner arch.
front may need a spacer removed

175/55R15 will go on fine with 4.15mm* of spacers (so that's a shade smaller OD than 195/50R15) at the rear, however 195/45R15 width will be fun to get everything clear, you might want to look at the 185/45R15 Nankang NS-2. At the front the main problem with the 175/55s was rubbing on various bits of plastic and metal, that is more than just spacer work, lock reduction & arch work would be required.

* To get a certain persons Alloys to fit I had 2.75mm & 1.4mm custom spacers made up.