90- the ZC final drive isn't bad at all, at least with its 1-5 ratios. The ratios in the ZC transmission are spaced a little better than in the USDM transmissions- they allow you to rev up a little faster, since you're using more of your rev range than in the Si transmission. The DX final drive is about the same as the ZC final drive- in the hatch, the FD is 3.722 (our reference section isn't correct, I'll fix it later), the FD in the STD is 3.888 (I think), and the FD in the sedan is 4.058. The ZC final drive is 3.888, and the Si final drive is 4.250.
solblu- If you put the ZC gears into a DX transmission, you're not changing the final drive much, unless you're dropping the gears into a sedan transmission.