The CR also know as the compression Ratio should indeed be lower then standard
That is why i tend to use Turbo engines, without the Turbo, they start with lowest CR
Your can hear the sound of this Pickup that it was on the “edge” but still ok.
The block had nearly a million Km on it, but still alive, i didn’t bother the compression testing, i just lowered the injection level and played a little with the timing untill the “knock” was acceptable… i still think the compression was low anyway…
At this moments, i am working on finding long stroke diesel engines to build them 100% gas and with some ethanol injection, automated.
Getting my hands on an old Isuzu block, DL200, 4 cylinder, with a bore of 79mm and a stroke of 107 mm ( 2,0 L or 122 Cu inch)
Its an old block, build untill 1966, but steel block and steel head…
The other, newer option, is the 4BD1 block and the 6BD1 block, 3,9Liters, 4 cylinder or 5,7 liters, 6 cylinders, both bore 102 mm , stroke 118 mm
Price rating for an overhauled block , 6BD1 is 2000,- $
Cheap here in SE asia and a large after market for spares and overhaul…
I think i can call the 6BD1 a big block ?