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There can be 300 degrees difference across a turbo!! Best to stay below 900!
What you want to see is pre-turbo temps. 1300 for very long--30 seconds- can be bad.
aluminum melts about 1275 but it takes some time at that temp.
you are readding the temp post turbo!!
 

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Many different things can cause high EGT.

1.To much fuel.
2.Needs more air ,or cooler air ( intercooler)
3.Better Exhaust .
4.bigger turbo .
5.timming.


The EGT probe needs to be pre turbo to have the right temp.

Scott
 

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The probe needs to go into the exhaust manifold right before the flange for the turbo, say about 1.5 inches up from the flange or so. A pyro after the turbo is worthless, too many variables for incorrent EGT readings.

Like this
 

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i'm also a bit interested in this thread. i was under the impression if i stayed under 550 deg. c. it would be ok. does this sound right ?
 

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This is what I remember reading: It's usually best to have it in the runner that is connected to #1 cylinder. The first cylinder has the most restriction, therefore it runs the richest and hottest.
 

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This is what I remember reading: It's usually best to have it in the runner that is connected to #1 cylinder. The first cylinder has the most restriction, therefore it runs the richest and hottest.
Well you will see that 90 percent of all pyro probes are in the back. I have mine in the 1,2,3 runner on my 6bt for that very reason. Just about every hood I pop to do pump work on will have the prob in 4,5,6. Whichever I guess. The cummins can withstand a constant 1200 degrees without any trouble, sustaining 1500+ for any length of time is not recommended. :nuke:
 

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Discussion Starter #14
Which turbo do you reccomend. Take a look at my pics I do not know if I can fit a bigger one. Very close to the oil filter relocation kit. Right now running a stock h1c. If it comes down to it I guess that I can drive down to knoxville and let you take a look lol
 

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You can get one off any 89-98 dodge 12 valve and cut the outside cylinders off.

Upgrading your turbo to move more air does not mean getting a physically larger turbo. You can put a smaller turbine housing on your H1C and get a lot more pressure out of it.
 

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That exhaust manifold is off of a 6bt 12 valve cummins. Hot Dawg cut 1 and 6 off of it and welded the ends up. Its a pretty common swap on the 4bts.
 

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Does anyone know where i can get a exhust manifold like the pic from dennyt above
I am using a 14cm3 exhaust housing with a 54mm compressor wheel. I also have made changes to my mounting of the alternator and A/C compressor. When I did my upgrade on the turbo the inlet of the turbo went from a 3" to a 4" and space was very limited. I will take some pictures tomorrow of the upgrade.
 

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i'm also a bit interested in this thread. i was under the impression if i stayed under 550 deg. c. it would be ok. does this sound right ?
I've been running my Isuzu regularly up to 750 deg C, it seems to survive okay. The occasional (accidental) excursion past 800 too.:puke:

Post turbo is a guessing game, shift the probe if you can.
 

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This is what I remember reading: It's usually best to have it in the runner that is connected to #1 cylinder. The first cylinder has the most restriction, therefore it runs the richest and hottest.


actually #6 is the most common cylinder to melt in a 12v and a 24 the later common rails like to eat #5 first them #6. though #1 has restictions the rear ward cylinders are the furthest from the air flow. i have run pyros on the front 3 and rear 3 on a 6 cyl as well as individual cylinders for testing on the 6cyl #6 ran the hotest #1 was the 3rd warmest. on the 4Bt things are a little more even but the rear cylinder is always 50-75 * warmer. i assume water flow may also influence this?
 
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