Compared to the Y's 21s, those wheels have 5mm less offset which will move them outboard 5mm. However the front rim you mention is 1" narrower, so the outside face of the rim 13mm further inboard; combine that with the offset and the outside face of the rim will be 8mm more inboard than the stock 21. The front tire width matches the 21s, so the tread of the new tire will be 5mm more outboard than the stock tire. The new rear tire is 30mm wider than the 21s, so it's tread will end up a total of 20mm further outboard (30/2 + 5) than the stock tread--over 3/4". Diameter will be in the neighborhood of 27", so you'll be about 1/2" lower. They'll fit and drive, but my guess after looking at my Y PUP is that the rears will rub the fenders over bumps. Just a guess though, I've not tried fitting them obviously. The new rears tread will be 10mm further inboard on the inside as well. Will that rub at steering lock? You'd have to fit them to see. Also, your car would be quicker with the new tires as the effective gearing would be lower due to smaller tire diameter.