more pan capacity because the 4v oil pump has more lash adjusters and cams to feed.
you can run a bird/cougar pan but you will lose some capacity.
side note, somewhere around 96, Marks got a "4v oil pump", previous years had a "2v oil pump". 4v one is thicker, more flow because 4 cams.
i used a "3v oil pump" which has even more flow, because cam phasers.