gasser vs. diesel egt temps

[dillenger1]

I was under the assumption that diesel combustion is hotter then a gasser.There was a guy on vortex that brought this to my attention.I googled it and sure is.they claim norm operating temps of 1600f.I thought steal melts at 1500f?

[jtanguay]

diesel combustion is indeed hotter due to the amount of energy stored in the fuel & how it is extracted.  BUT egt's on a gasser are hotter due to the way that their engines work.  in a gasser the fuel is still burning a bit even when exiting the engine.  in a diesel the gases are still expanding, but most of the heat created is turned into mechanical energy.  if you advance the gasoline timing, then you will actually cool the engine a bit.  retard it enough, and you'll burn the engine in very short order.  too much crap to think/worry about... diesel is much simpler even if you take into account the dial indicator, and the +-0.05mm timing  :lol:

i think they use plasma coatings on most parts so that they can withstand high temps.  i'd imagine all gasser turbine wheels to have some sort of plasma coating or other.

those old saturns ran some pretty crazy retarded timing... but the motor was built for it and they were able to achieve some really crazy MPG's.  i'm still amazed at how little my dads old '02 saturn consumed (5 speed).  people really had to push the automatic ones to flow with traffic, and so would usually burn the rings/valves and then start burning oil (that nice blue smoke out the exhaust)  now you see saturn with a hybrid that gets about 32mpg, when their earlier designs were getting somewhere in the range of 40mpg WITHOUT hybrid systems!!! /rant  :lol:

[88jetta350]

 people really had to push the automatic ones to flow with traffic, and so would usually burn the rings/valves and then start burning oil (that nice blue smoke out the exhaust)

If more americans weren't so lazy/stupid as to refuse/fail to learn to drive a 5-spd, you wouldn't have problems like this. I learned to drive a standard in 10 minutes.  :roll:

[jtanguay]

 people really had to push the automatic ones to flow with traffic, and so would usually burn the rings/valves and then start burning oil (that nice blue smoke out the exhaust)

If more americans weren't so lazy/stupid as to refuse/fail to learn to drive a 5-spd, you wouldn't have problems like this. I learned to drive a standard in 10 minutes.  :roll:

don't forget Canadians  :wink: manual boxes really let us connect to the road and just simply drive better due to being aware of our surroundings.  

i'll have to agree that most people that don't drive standard are just too lazy/stupid for it.  i've heard of so many idiots getting 5 speed only to burn out the clutch early or even do some really bad damage (i've heard of one girl damaging the driveshafts beyond repair... wtf??? drag much???  :lol:)

[Turbinepowered]

diesel combustion is indeed hotter due to the amount of energy stored in the fuel & how it is extracted.  BUT egt's on a gasser are hotter due to the way that their engines work.  in a gasser the fuel is still burning a bit even when exiting the engine.  in a diesel the gases are still expanding, but most of the heat created is turned into mechanical energy.  if you advance the gasoline timing, then you will actually cool the engine a bit.  retard it enough, and you'll burn the engine in very short order.  too much crap to think/worry about... diesel is much simpler even if you take into account the dial indicator, and the +-0.05mm timing  

Then too you have to take into account the volume of air that heat energy is being transferred to. A gas engine will not have its full piston swept volume of air to accept the heat load from combustion, due to the throttle plate's restriction to create a stoichiometric condition for combustion. A diesel has the full piston displacement of air to accept that heat load each and every time fuel is burned, which results in less energy per molecule than the gas engine.

[jtanguay]

diesel combustion is indeed hotter due to the amount of energy stored in the fuel & how it is extracted.  BUT egt's on a gasser are hotter due to the way that their engines work.  in a gasser the fuel is still burning a bit even when exiting the engine.  in a diesel the gases are still expanding, but most of the heat created is turned into mechanical energy.  if you advance the gasoline timing, then you will actually cool the engine a bit.  retard it enough, and you'll burn the engine in very short order.  too much crap to think/worry about... diesel is much simpler even if you take into account the dial indicator, and the +-0.05mm timing  

Then too you have to take into account the volume of air that heat energy is being transferred to. A gas engine will not have its full piston swept volume of air to accept the heat load from combustion, due to the throttle plate's restriction to create a stoichiometric condition for combustion. A diesel has the full piston displacement of air to accept that heat load each and every time fuel is burned, which results in less energy per molecule than the gas engine.

thats also a good way of putting it.