How to ENABLE / DISABLE RAC for single instance oracle_home installation?

To Enable :-
$ cd $ORACLE_HOME/rdbms/lib
$ make -f ins_rdbms.mk rac_on
$ make -f ins_rdbms.mk ioracle

To Disable :-
$ cd $ORACLE_HOME/rdbms/lib
$ make -f ins_rdbms.mk rac_off
$ make -f ins_rdbms.mk ioracle

Other options :-
RAC - {rac_on OR rac_off}
RAT - {rat_on OR rat_off}
OLS - {lbac_on OR lbac_off}
DV - {dv_on OR dv_off}
ASM - {asm_on OR asm_off}
OLAP - {olap_on OR olap_off}
PART - {part_on OR part_off}
CTX - {ctx_on OR ctx_off}