Anyone out there know the temp difference with having your probe mounted pre-turbo at the back of the passenger manifold vs. post turbo in the top of the downpipe? Getting ready to install an EGT gauge and am curious. Don't like the idea of pre-turbo just incase the probe decides to break, but would rather have that so the reading is more realistic. But if the difference isn't too much, i'll mount it post turbo. Thanks in advance.


Ken

I don't think there's any hard rule on that since it depends on where you mount, the exhaust system behind it and a couple of other variables. The concesus from guys who've done it seems to suggest there's about a 300 degree difference between the two, but the only way you'd know for sure is if you had both to compare on your truck.


For what it's worth, the pre-turbo location is more accurate and the stories about probes breaking off seem to come mainly from old 18 wheeler folks. I guess at one time that was a consideration, but with the current materials and anticpated mileage you might drive, I don't think I'd worry about it. If you do use the truck for a lot of miles, all you'd have to do is check the probe condition once in a great while. In my experience with EGT probes used on aircraft, they'll usually quit working long before they'd have broken off.

You will see the avg temp from pre to post being around 300-400 degrees lower post post turbo.



What you won't see post turbo is the spike when you are running hard..........I have seen my Autometer Pre Turbo EGT bury a 1600 degree gauge............





Thttp://www.dieselplace.com/forum/smileys/Clown.gifNY

Thanks for the input guys.

I run BOTH pre and Post turbo si i know what temp my turbo is at when i shutdown the engine and i will say this... hauling on level ground no headwind and appz 10Klbs yields almost no difference in readings. BUT throw in a hill, some altitude and some headwind and it is a whole different ballgame. the preturbo probe measures changes instantly , while the post turbo probe takes 10 seconds to catch up (if it ever does) and there is more than 400F between the 2 of them... going up a hill i had a preturbo reading of 1350F(and climbing) and a post turbo reading of 850 and climbing.


The preturbo gauge was climbing faster than the post turbo gauge.





Don't guess with a 10K motor....preturbo is the only way to go.

Ditto Got Juice. Mine does the same, and I have seen 500 degrees difference.

Thanks again guys. I think I will go with the pre-turbo setup.


Ken

Ditto Got Juice. Mine does the same, and I have seen 500 degrees difference.


Yup, on on those long gradual hills...OMG!!!!


lol... i have looked over at my post turbo gauge and laughed and said "Gee if only my temps were that low.... i could go up another power level!!!!)

Juice


What is the longest you have held it at say 1200 degrees.


Genohttp://www.dieselplace.com/forum/smileys/Hug.gif

Juice


What is the longest you have held it at say 1200 degrees.


Genohttp://www.dieselplace.com/forum/smileys/Hug.gif





1250F 15 minutes at stagleap (Kootenay mountain pass)


FredW knows the pass well.... 8% for the last 15 miles... i was loaded with 8 double lifts of 10.00 mm no core sheeting on a 30' gooseneck. juice on 0/0 WOT 4th gear, ambient temperature was -7C

on edit the pass is something like 4000'ASL IIRC


BTW 8 double lifts is 1280 sheets of sheeting.


Edited by: Got Juice?

I HAVE INSTALLED MY PYRO GAUGE PRE TURBO NOW WHERE DO I PUT THE SENSOR FOR THE 6-GUNN SPEED LOADER

I agree with Zeeb


Many years working on industrial engines the probe sensor will quit way before you loose the end off it. It quits reading temps the probe should be the first thing to check.


Genohttp://www.dieselplace.com/forum/smileys/Hug.gif

I HAVE INSTALLED MY PYRO GAUGE PRE TURBO NOW WHERE DO I PUT THE SENSOR FOR THE 6-GUNN SPEED LOADER


Where did you put your pyro gauge sensor? Passenger side? I had my Isspro pyro probe for the A-pillar gauge in the passenger side, so I put my probe for the Edge Attitude in the drivers side. There's a nice open spot for drilling/tapping the driver's side from below just forward of the manifold rear flange and the oil filter mount.


Edited by: Idle_Chatter