Originally Posted by DK9mm
Is the topic about the OFNA JL red dot .12?
I have three shims on mine as well and will be running 20%.
Should I remove one shim during the break in process or after?
I broke in my own with 20% leaving the default shims on. didn't see anything wrong, you would lose compression though if you run with 20% as Shawn said.
I don't know what mm shims to use for 20% though. I've been running the engine for about 3 months now and changed the con rod a few weeks back and i'm still using 20% with the default shims.