What's your definition of "very high RPM"? My small block round track engines live very happily at 7,000+ RPM, with anywhere from one to all 8 cylinders sleeved. I leave a small step at the bottom of the cylinder for the sleeve to bottom against, and the cylinder head holds it down at the top. RPM isn't a factor if the sleeve can't move. I also bore the block to a .002" interference fit and drive the sleeves in. I've recycled a lot of my competitors' "junk" blocks by sleeving them back to standard bore after they were discarded as "worn out". Nothing gives me more satisfaction than outrunning somebody with his own castoffs!
Jerry
Last edited by Hotrod Lincoln; 05/23/2011 4:50 PM.