Cleaning build up on piston tops?
 

I just aquired a set of pistons for a 6.2L engine (M119) build I'm working on. The pistons have the usual carbon/crud buildup on the tops and I'm wondering what to use and how to use it to clean the tops... They are factory Kolbenschmidt but are 101.97mm, oversized. Don't want to scrape and score the tops but I want them a little cleaner. Is there something I can soak them in first? Any help is appreciated. Thanks!

Those deposits are very tenacious. I've cleaned pistons by scraping. It's just a matter of finding a scraper with just the right amount of dullness/sharpness. You don't want the scraper so sharp that it'll gouge the aluminum, but sharp enough to remove the deposits. I then follow up with Scotchbrite soaked in oil.