I am getting some 17x7 +45F, 17x8 +45R wheels...
For tires, I am not sure if I should get 225/245, or 215/245.

For suspension, just Konis/springs/t1r strut. UK spec alignment.

Would you guys recommend 225 over 215? It's a street driven car with some spirit.

225 would make the handling more neutral, improve braking, etc...
215 would be lighter/cheaper, sharper turn in (right?), and "safer" (more understeer), ap2 sizes...

other info: getting falken fk-452. 225 is "reinfored" while 215 size is not... 245 is.

215 tread width is 7.6in
225 -- is 8.1in
245 -- is 8.8in

recommendations would be appreciated. thanks.

my first s2k was on 225/255 and i loved that, but it also had a custom alignment, t1r strut, and bc race spec coilovers.

right now im leaning towards 225/245..

 

225/245 gets my vote. 215s to me in the front is too narrow

 

sweet, thanks.. 215s are pretty narrow.. but im not so much looking for maximum grip (not going to autox this one), but just the right stagger for the feeling i want.. which i cant describe anyway so whatever! haha

 

Just out of curiosity, I thought increasing the width of the fronts would INCREASE understeer as opposed to aiding in relief of it. I'm thinking of similar sizes and this is something I am thinking about myself. I could be wrong, can someone verify this as well?

 

You pretty much nailed the pros and cons. I'd stick with a 215 on a 7" wheel though.

Adding width to the front will increase OVERsteer, although in this case probably not enough to notice except on a track. As an exaggeration, let's say you put 275's on the front leaving everything else stock. You have way more grip in the front so the back end will lose traction in a corner first.

 

Correct. I thought losing traction in the front first was understeer?

Ah, so confused.. Anyway, I want a LITTLE more traction in the rear than the front - safer and easier to correct on the street.

The Falken site says 215 and 225 will both fit on the 7'' wheel, The 225 might be bit bulged, though.. I don't think these "run wide" comparatively.

Also not sure if I want that "reinforcement" of the 225, which the rear at 245 WILL have.

 

I decided on 225/245 I think.. and I don't think I'll get the strut bar anymore.

Would you guys set the shocks to the same level F/R? Or rear a tad stiffer?

 

225/245 will have the fronts looking too beefy relative to the rears, imo.

Handling won't be tremendously different either way.

Personally, with 245 rears, I'd go 215 fronts.
255 rears, either 215s or 225's.

 

Thanks for the tip. Wonder how 225s can look beefier (relatively) than 245s without taking wheel width/offsets into consideration.
215 says wheels 7-8
225 says wheels 7-8.5
245 says wheels 8-9.5
The only thing to consider now is the reinforced sidewall in the 225s and 245s, but NOT in the 215s...

 

225mm is 8.85". Total of ~.85" of bulge or .43" per side on a 7" wide rim (which is ~8" outside lip to outside lip).
215mm is 8.46", total of .46" bulge or .23" per side.
245mm is 9.65", total of .65" bulge or .32" per side on an 8" rim.
(the above bulge numbers are by no means absolute...)

Another contributor to the bulkier look of the 225/45-17 vs. 215/45-17 is that the 225's diameter is ~.4" bigger. 25" vs. 24.6" for RE01R's, while the 245/40-17 is 24.7". The 225 will bulge out more than the 245, and will have a bigger OD, which will make it look like the front tires are quite a bit bigger than the rear tires.