Your wrong. My son installs them they are sizing balls you push through the bronze liners. If I get to the shop I will get some pictures of them. They also have pilots you push through now. I just called him to confirm what I stated. He laughed and asked if it was the same guy that uses the pistons to square deck a block.
He does this work every day for many auto and cycle shops that bring their machine work here . I just saw him doing some heads for a "shovel head" Instead of bronze guides these are bronze liners, There are boxes and boxes of different liners in the cabinet. Knurling is for shops that can't afford the tooling to install liners. You can control the sizing of the stem to guide clearance more accurate.
The new tooling is a hour glass looking pilot. More expensive I guess.
Some of you should not give advice if you don't know. I know I will not unless I talk to my son who is up to date on tooling. For those of you that are close to me you all can stop in when ever you want for work to get done..
Dave comes here all the time 1969383valiant he can confirm what I am saying. when my son does work the finished parts always get set on a clean shop towel. All completed heads and motors are bagged or shrink wrapped. He is very clean & meticulous with his work. Nothing goes out the door unless it is perfect.
He cares more about pride then money. He does this work on the side and there is no shortage of work due to his reputation in our area.
