The R4 installation process automatically sets your R4 partition to be a bootable device.  In other words, you shouldn't need the boot floppy after you install.  However, there are a couple of situations in which this mechanism may fail...
R3, East of R4
If you install R4 on a system that also has an R3 partition (whether it's on the same or a different disk), booting into the R3 partition may make the R4 partition unbootable.  If this happens to you, do this:
$ makebootable -safe /boot
|
$ makebootable -full /boot
|
IDE and "Large" Mode
Some IDE disks are set to "large" mode. 
Such disks probably can't be
made bootable. 
If you're using a large mode IDE disk, you'll have to
boot off of the R4 boot floppy. 
Sorry.