The F22B2 I don't know about... my knowledge is limited to 4th gens. I paid only $60 for my manifold from a salvage yard and swapped it in and oh my god what a difference. The second runners open at 3500rpm and the car just screams and pulls great up to redline, much better than with the stockie. I have pictures of the difference between the two manifolds, quite inpressive. Good for a factory rated 10hp, which is REAL hp. Hands down the best bang for the buck for an older 4th gen...

Difference between the two. F22A4 left, F22A6 right:
http://www.geocities.com/lonslo_90/F...ifold_diff.jpg

Click on link, then add a space to the end of address. Or right-click, save-as