It wouldn't get into the combustion side, as it would be confined / trapped in the thread clearances only, unless you over apply it... but you're doing the repair cylinder off the crankcase, so there wouldn't be any residue to flake away. It was designed for firearm use mostly, it works in a similar way as gulling, but the ceramic has a breaking / shear point when removing the fastener. Any of the high temp red thread locker will be more than adequate

It doesn't exhibit much if any real locking properties... red locker properly applied, would be more difficult to remove without heat applied... if the rifle barrel gets well above 450F then the red locker will fail obviously, hence the use of ceramic particulates, and water based mind you... which may pose an issue from combustion moister working its way past voids in the ceramic. Not truly impressed with it, but it has its applications.