Well looking back at this thread my expectation was to encourage additional information from other OSS members to be added to this thread, although there was some I guess my expectations were greater. That being the case this will be my last input of information in this thread for the remainder of this year.
The following information can be used for race or street engines, several Worldclass engine builders have known and have been using the technique for decades.
If you REALLY want to have cylindrical cylinder bores when it comes time to hone your cylinder block, the block needs to be at operating temperatures. Getting the block up over 120f degrees is a good temperture to hone it, but if you can get it to 150f degrees, it’s even better. In addtion any honing oil that you use must be of equal temperture of the cylinder block, when the cylinder block is heated and you douse cold honing oil on it and then hone it, the localized cooling is going to distort the bore.
Many times people ask me how I am able to consistantly build long term reliable high HP race engines, well M8’s this is one of my secrets.