Originally Posted by larry4406
Ignorant question here - what does one gain from using one of these short of leak detection? Engine break in?

Among other problems yes. A friend at work had an engine built and then built a stand to break it in before swapping it into a nice survivor 442.
It would also come in handy for selling engines as everyone wants to see it run before they buy. Many people have done this with front subframes but who wants that layin around?