Paper Size, setuserpapersize

im using PIN printer to print a cash bill,

the paper size is 8.5 inch x 5.5inch (half of normal fanfold size)

so, the preloaded papersize in crystal report 9.2 doesn't have such paper size, so i need to set it myself

VB Code:

myReport.PaperSize = crPaperUser
myReport.SetUserPaperSize length, width

refer to the help file in crystal report, the length & width value is in pixel, 1 inch equal to 1440 pixels right?
so 8.5 inch should be 12240 pixels & 5.5 is 7920, but end up not what i want.

after few hundred tries, i found that 1335, 2100 nearly equal to 8.5 x 5.5 inch, why?

anyway to change the scalemode of it to cm or inch?