Changing CONFIG_BLK_DEV_RAM_SIZE

I got Linux 2.4.x running on my embedded systems board. I like to
change the default value of  CONFIG_BLK_DEV_RAM_SIZE to 8192, but
whenever I run 'make xconfig', it shows the default value to be 4092,
but I am not sure which file it is using to come up with the 4092
default value. Any clues?

I searched for all the files in the tree and there are many places
where there are definitions of this parameter, but many of these files
are generated files. Where is the source file for the variable?

Thanks