schiker
Well-Known Member
The torque vs hp is hard to argue one way or the other for speed vs pulling.
What would put this all to bed is have a couple of trucks dyno'ed with stock injectors vs marine injectors. I believe the difference in graph's would be the torque and HP would shift higher in RPM range and both be higher for a "marine setup". The gain would be from 2 reasons: the amount of fuel injected is based on fuel rate and rpm of the engine. The higher the RPM or more injections equals the more fuel is burned and more power generated. And the timing advantage of the marine injectors combined with higher rpm work well together.
Bill's record truck runs really high rpm and he setup marine type HO injectors and he was going for high rpm and hi speed. I suspect When he builds "tow" trucks he recommends stock injectors because he wants the power band to be better matched to a trucks working rpm expected.
Can you change gear or propeller pitch and gear etc to change tactics yes. Its just not likely you will limit a boats rpm to the midrange of an engines rpm range to reach top speed (highest drag load) nor have a truck run til redline to have best grunt pulling power.
One nuance to matching high RPM and high precup heat (both from faster injection, bigger flame front, and higher fuel flow - from rpm and fuelrate/pump stroke) is at higher water pump rpm allows higher flowrate/turbulence of cooling water. I have put on a smaller water pump pulley to help increase cooling on a stationary diesel engine (increased water pump and fan speed).
What would put this all to bed is have a couple of trucks dyno'ed with stock injectors vs marine injectors. I believe the difference in graph's would be the torque and HP would shift higher in RPM range and both be higher for a "marine setup". The gain would be from 2 reasons: the amount of fuel injected is based on fuel rate and rpm of the engine. The higher the RPM or more injections equals the more fuel is burned and more power generated. And the timing advantage of the marine injectors combined with higher rpm work well together.
Bill's record truck runs really high rpm and he setup marine type HO injectors and he was going for high rpm and hi speed. I suspect When he builds "tow" trucks he recommends stock injectors because he wants the power band to be better matched to a trucks working rpm expected.
Can you change gear or propeller pitch and gear etc to change tactics yes. Its just not likely you will limit a boats rpm to the midrange of an engines rpm range to reach top speed (highest drag load) nor have a truck run til redline to have best grunt pulling power.
One nuance to matching high RPM and high precup heat (both from faster injection, bigger flame front, and higher fuel flow - from rpm and fuelrate/pump stroke) is at higher water pump rpm allows higher flowrate/turbulence of cooling water. I have put on a smaller water pump pulley to help increase cooling on a stationary diesel engine (increased water pump and fan speed).