Airram.com offers some performance stuff for 4.7’s and would be a good source. I searched Amazon and found a master rebuild kit for the 4.7 with .20 oversized pistons. My engine builder is also an excellent resource, Dennis Chencharick, his shop phone is (814) 238-1578. Not a lot of options for a 4.7. I happen to have a 2002 Grand Cher with a 4.7 H.O.