Thread: Strange EGT and boost issues...

I suspect this is normal , I have the same experience in the 300tdi disco and R380 , Climbing up a big hill in 5th , engine under considerably more load , drop back to 4th ,she starts droping EGT even with pedal to metal.

the engine is outputting less torque so you're not loading it up as much.

less load=less heat

perfectly normal.

what he said

higher reves = less time for the hot gass to stay in the cylinder before being replaced with cold

Originally Posted by Blknight.aus

the engine is outputting less torque so you're not loading it up as much.

less load=less heat

perfectly normal.

But the "load" is the same. You are still pushing the same mass at the same velocity. I am sure the torque output of the engine would be the same or higher.

Hoowever - I can understand the concept that Clean32 describes - higher revs = hiigher flow rate of air - I just thought that would be compensated for by extra fuel.

Originally Posted by isuzurover

But the "load" is the same. You are still pushing the same mass at the same velocity. I am sure the torque output of the engine would be the same or higher.

Hoowever - I can understand the concept that Clean32 describes - higher revs = hiigher flow rate of air - I just thought that would be compensated for by extra fuel.

Torque would be same at wheels but less at crankshaft because the gearing multiplies engine torque.

Originally Posted by isuzurover

But the "load" is the same. You are still pushing the same mass at the same velocity. I am sure the torque output of the engine would be the same or higher.

Hoowever - I can understand the concept that Clean32 describes - higher revs = hiigher flow rate of air - I just thought that would be compensated for by extra fuel.

ok there are 3 things to consider

1 as i already wrote, the sink time for heat to transfer though the liner and to be removed by the coolant is reduced at higher reves, this is because the dwell time or burn time is reduced thus more of the heat is removed ver the tail pipe.
2. the speed you are traveling at ( including load dictates the amount of energy you need IE how much fule you will be using. so regardless of what gear you are in you will be using the same amount of fuel.

3 because you are at higher reves burning the same amount of fuel. that means you are using less fuel per burn just that there are more burns per distance traveled. now with a NA motor that would ,mean that there is a full cylinder of cold air each burn with a lesser amount of fuel. with a turbo this effect is greater. at 10 psi is about 1.3 times the amount of air.

Originally Posted by Bush65

Torque would be same at wheels but less at crankshaft because the gearing multiplies engine torque.

Ah, yes of course. Thanks John!

Mine behaves in a similar way. On a hill will make 550 deg and 11 psi at 100 ks in fifth but have to change down long before the gear fails due to the weakness of the Santana box
I actually lose speed by changing forth as out of its best torque curve, make less boost (9 psi) and have a much lower egt even if I nail it. Think mine needs pump work