Doing some math at work today and here is what I came up with. You can have the equivalent of these FD's if you had these wheel sizes. (some of which you will not find!)
195/55 R15 (stock) =4.4
205/45 R16 =4.43
205/50 R15 =4.47
205/45 R15 (Nittodrag) =4.7
205/40 R16 =4.59
195/40 R15 (made up) =4.88
205/35 R15 (made up) =5.00

So if you where able to get some nitto drags it would almost be like switching to a JDM final drive. The only problem is the weight differences in wheels/tires and where the weight is located on said wheels/tires. Where as the FD change would be strictly a gearing change. Also if you already had one of these tire sizes the FD would still change your ratios by .475 Anyways just real busy at work so I thought I would figure something out.

 

You missed commercially available 195/50/15s. I have those, but I dare not drive it on the streets... sidewall is way to short and it bends rims like crazy.

 

what about the now defunct yokohama avs 195/45-15?

 

Here ya go!
195/50=4.54
195/45=4.7