Crank scrapers or plate...?
So we have all the education needed on crank scrapers, interesting insight rounded off with facts.
Still I am with pishta... OP didn't say a word about what engine he's building, and I don't see it being
a race engine...
Doesn't need to be a "race" engine to benefit from a scraper. Don't repeat things that are wrong. You are training your mind to accept a mistake every time you repeat it.
Obviously, RPM is a function of when you need a scraper, but stroke length and crank case volume are WAY more important than RPM. Entrainment, gas expansion, blah blah blah...Id have to go get my notes from several conversations with Kevin Johnson but there is way more to it than RPM.
The OP was already looking I no scrapers and windage trays (I use both) and instead of helping him, some tried to discourage him. It's especially frustrating to see guys wanting to learn and get shut down because it's not a "race" engine.
The cost of a scraper is relatively little for the gain.
BTW, I have had some very intimate conversations with my engines, and not a single one knew it was a race engine until I told it what it was.
Sometimes it's like it's a jealously thing....because a guy wants a part that someone else has classified a "race" part we start measuring weenie lengths.
FWIW many parts today were considered "race" parts just 10-15 years ago.