Mako Vunipola has been named among England's replacements for the championship decider at the Millennium Stadium, while Faletau will start for the home side.
The Tongan-born flanker told the Welsh Rugby Union's website: "If he comes off the bench and I'm still on the pitch it will be a great occasion for both of us and our families.
"It's a shame [Vunipola and his brother Billy are] not playing for Wales but they came through the English system. I'm really pleased they're playing international rugby and want them to do well.
"Mako's been great coming off the bench for England he did brilliantly on his first start against Italy. It's been great to see him doing so well and I'm sure he will be the same tomorrow."
England can complete the Grand Slam with victory, while Wales need to win by at least seven points to secure the tournament.