Normal-mine can drop to 200 on a long downhill.

 

Coming down a hill, you're only pumping air through the engine. 200 degF readings pre-turbo aren't unusual at all.

Rusty

 

As far as I have read on this forum. The reason for pre turbo is if your egt's get to like 1500* for too long your turbo goes buybuy. And because of racing and other stuff.

 

And pistons, etc, etc.

 

That's pretty cool. I've kind of been wondering if there was any to check calibration on these guages. I've never seen the equipment.

 

Newbie question. What's the best procedure for cooling the engine down when pulling a long grade and temps get dangerous on the pyro gauge?

Just slow down, or pull to the side of the road and allow to idle?

Just curious for future reference.

 

Slowing down a bit, or gearing down to raise the RPM is usually enough.

Also, my thought is that a probe will last longer if it is mounted post-turbo, because it won't see the extreme temperatures. Any opinions?

 

Type K thermocouples and their thermowells are generally good for over 2000 degF. Why don't you ask how many have had pre-turbo probe failures that have damaged the turbo?

Rusty

 

I agree. I have heard that the probes are very unlikely to melt and come apart. I was thinking about the probe simply wearing out and/or losing accuracy.

 

EGT should be measured pre-turbo. As the hot exhaust gases expand through the turbo's turbine, the pressure drops; so does the temperature, just like any other time gases expand. The higher the turbine inlet pressure, the greater the temperature drop across the turbine.