|
I'm sure it is critical, and it's probably the brick wall setting a lower limit below which things wont work anymore. What i'm interested in what things can take it as low as possible whether it gets me 10% lower or 20% lower than would normally be the limit.. and curious why some engines seem more resilent than others. People running diesels at 800rpm in another thread for instance. And Listeroid engines run 600rpm off standard diesel with pretty familiar bore/stroke of 4.5" and 5.5" respectively.
Long stroke short rod increases piston speed away from TDC at least during the critical first part of the stroke. Piston speed is not a constant afterall and expansion is most needed after you trigger ignition. Someone else said combustion chambers matter - I was hoping they'd expand how, or what would work better. Also said EGR would slow it down. My own suggestion that slower burning fuels like producer gas should hopefully tolerate slower speeds as well. I don't know how slow I can get it but rather to stretch it. 1200rpm at highway speeds in 6th already done by the dodge viper v10 i'm told. I had a 62 chevy that would idle at some 200rpm once but I never put a load on it.
The ugly harmonic vibration seems to be both the reason it's hard on the engine and an obvious sign something is not working properly... that to me seems the first barrier to tackle even if there are other potential problems. After that can look at what else pops up as a side effect of the slow flame fronts, needing lower compression and such maybe.
|