Placement of EGT probe

[BIG BOB]

I normally shut mine down when the post turbo temp goes below 325 degrees. This often takes 3-4 minutes when the outside temps are in the high 70's to low 80's.

For post turbo, 325* seem high. I know that pre-turbo I let mine cool to 310* and it only take 3-4 minutes.

 

[SKargo]

Mine is post turbo and I shut it down under 350°



I think the argument is ridiculous, because we never hear of any overheating issues from people running them post turbo. I have my x-monitor's alarm set at 900°, and it hasn't hit it yet.



Oh, and I know some truckers with hotrodded engines who are still post turbo, guess I better tell them you guys said they are wrong. :-laf

 

[Bertram65]

Mine is post turbo and I shut it down under 350°



I think the argument is ridiculous, because we never hear of any overheating issues from people running them post turbo. I have my x-monitor's alarm set at 900°, and it hasn't hit it yet.



Oh, and I know some truckers with hotrodded engines who are still post turbo, guess I better tell them you guys said they are wrong. :-laf

Mine is post as well I try to shut down at 300 degrees or less, some times if I am in a rush I shut down a little higher.

Don't forget to tell Cummins as well seeing as they reconmend post turbo.

 

[BIG BOB]

Mine is post turbo and I shut it down under 350°



I think the argument is ridiculous, because we never hear of any overheating issues from people running them post turbo. I have my x-monitor's alarm set at 900°, and it hasn't hit it yet.



Oh, and I know some truckers with hotrodded engines who are still post turbo, guess I better tell them you guys said they are wrong. :-laf

Certainly don't want to start an argument here. There is no right or wrong as far as post or pre turbo. It really depends on your preference and the reaction time that you want. If a guy is running a lot of fuel, high HP and tows, he might prefer, like myself (not real high HP, but tow) to monitor the temps closer to the piston chamber to prevent a melt down. Piston damage happens much more often than turbo damage while running down the road. In fact, I can't even remember anyone on TDR or DTR having a turbo fail because of high EGT's while running down the road.



Where turbo damage is usually happens is when the engine is shut off after running hard pulling a hill or freeway. Shutting the engine off with high EGT's will cause pre-mature turbo failure because the oil will bake on the bearings. This is why it is a good idea to let your EGT's cool to 300-310* pre-turbo before shutting the engine down. I don't know exactly what the parameters are for post-turbo, however I know they have alway been lower that pre-turbo.

 

[Bertram65]

Certainly don't want to start an argument here. There is no right or wrong as far as post or pre turbo. It really depends on your preference and the reaction time that you want. If a guy is running a lot of fuel, high HP and tows, he might prefer, like myself (not real high HP, but tow) to monitor the temps closer to the piston chamber to prevent a melt down. Piston damage happens much more often than turbo damage while running down the road. In fact, I can't even remember anyone on TDR or DTR having a turbo fail because of high EGT's while running down the road.



Where turbo damage is usually happens is when the engine is shut off after running hard pulling a hill or freeway. Shutting the engine off with high EGT's will cause pre-mature turbo failure because the oil will bake on the bearings. This is why it is a good idea to let your EGT's cool to 300-310* pre-turbo before shutting the engine down. I don't know exactly what the parameters are for post-turbo, however I know they have alway been lower that pre-turbo.

Actually the turbo acts as a heat sink so pre turbo will read a lower temp sooner after a hard run than post turbo, so if you had both probes on the same engine, for a period the post will read higher until the heat is removed from the turbo. The "always lower" only applies when you are under power.

 

[rbattelle]

Actually the turbo acts as a heat sink so pre turbo will read a lower temp sooner after a hard run than post turbo, so if you had both probes on the same engine, for a period the post will read higher until the heat is removed from the turbo. The "always lower" only applies when you are under power.

I agree. By the way, this debate has raged here for a long long time (read me and CJEliassen get into it pretty heavy here ). It will never be settled - Big Bob is right, there is no universal "right answer" - it depends on your particular setup. If I had performance enhancements I'd have a pre-turbo gauge first. Eventually, I plan to have both just for amusement.



-Ryan

 

[BIG BOB]

Actually the turbo acts as a heat sink so pre turbo will read a lower temp sooner after a hard run than post turbo, so if you had both probes on the same engine, for a period the post will read higher until the heat is removed from the turbo. The "always lower" only applies when you are under power.

Thanks for the clarification. I've never run post turbo, alway wanted to know what the cylinder were doing.

 

[KingS]

mine is post turbo and it respond instanly to even a tap of the throttle so I don't see how it can respond any faster then instantly but my pyro is drilled and tap through on the down pipe of the turbo on passenger side of it there is a round about penny size bump out on it I center punched it and drill and tapped it in there and according to a temp probe that is magnetic and attached to my dad high dollar ohm meter and stuff he uses to check bearing temp and fan temp for nuke power plant smoke stack fan its not that different in responce time and and only allitle off on temp but I use the standard that every one else uses for the max temp any ways

 

[BIG BOB]

mine is post turbo and it respond instanly to even a tap of the throttle so I don't see how it can respond any faster then instantly but my pyro is drilled and tap through on the down pipe of the turbo on passenger side of it there is a round about penny size bump out on it I center punched it and drill and tapped it in there and according to a temp probe that is magnetic and attached to my dad high dollar ohm meter and stuff he uses to check bearing temp and fan temp for nuke power plant smoke stack fan its not that different in responce time and and only allitle off on temp but I use the standard that every one else uses for the max temp any ways

It's not just about how fast your pyro re-acts but the cylinder tempertures. You will see somewhere in the vicinty of 200* different in temp pre and post turbo.