HDI,hope i didnt offend?
what i'm trying to convey,is, all diesels could be reffered to as Direct injection engines!
in reality, they all inject fuel into a chamber, no matter where its located, wether its in the head(pre-chamber) or in the piston crown.
both have some advantages, but for reducing fuel consumption ,chamber in piston has proven the best(so far).
DI in Piston,in the early mechanical inj., had noise and emission problems,(not able to control volume and timing properly). and very hi cylinder pressures(things had to be built heavy and strong). a disadvantage! and required hicomp.ratio to start in cold temps.
the advent of elec. Piezo injectors and a silly computor to manage multi-phase injection processes, has changed all that.
pre-chams. had extremly hi swirl and made cold starts easier,with glow plugs,(glow plgs were(are another system to fail).
it seems, finally after many yrs, that the latest designs,that lower comp.ratio and lighter component parts, things are better overall!
some thing that should be aware of,Diesel fuel itself has changed, from the 40-50s to new formula that is out today, higher Cetane and other added products, like combustion enhancing additives, the negative to the fuel is it does not give the MPG that the old fuels had ,BTUs per given volume, simply does not have the energy that the old had .
but it is a cleaner burning fuel, so we will have to just pay out more money to save the planet, course we do know that when the polluting humans are gone, the planet earth will still be here,changed but still here.
i'm ranting so???