They were a good engine for the day but unfortunately they got an undeserved bad reputation for blowing up because they asked too much of them.
They finished up putting these in multi wheelers plated at 26 tonnes, imagine that 26 tonnes from 3 1/2 litres.
Another fault was they were brilliant starters, basically one compression and they were away, trouble was the driver would press the button a quick stab and it would fire but occasionally if it didn't it would bounce back and could start up in reverse. Once running in reverse the governors didn't work, going the wrong way for centrifugal force to throw in so it went to full chat plus a bit more.
That had a knock on effect of causes a crankcase vacuum and it started to suck oil up from the sump and burn this. Add together high revs, over speeding and lack of oil and it was a disaster waiting to happen. What usually happened was that before it had chance to seize it would get all egg bound and throw the rocker shafts out the side of the engine.
You couldn't stall one, just too much power plus all the exhaust was now coming out the air intake and filling the cab up prompting the driver to run away

We had one in one day for service and struck it up and it went backwards, our boss who had a lot of experience with these calmly got a fire extinguisher and let it go straight up the exhaust pipe and it died out.
To get back to the OP (sorry

) did anyone notice the electrically assisted turbo's ? These type of engines can't start without some for of boost hence the supercharger on the original.
A lot of these engines finished up in universities where they studied them to get even more power out of them, they started off using a supercharger driver off the engine and the engine drove a turbocharger where at some stage the supercharger was disconnected as it takes a lot of power to drive one.
That extra power then cause the exhaust gas volume and temp to rise and it was a spiral.
In the end they were taking the power output off the turbocharger shaft thru differential gearing and getting more power by just using the engines as a gas generator.
If you can get a copy (very expensive now ) see L J K Setright's Some Unusual Engines.
John S.