EGT Probe Location

[shorthorn]

So I just got the EGT probe in for my Edge CTS and getting ready to install it... I have read 100 articles on the topic.. with 100 different locations where to put the damn thing!

I know for fact I want it pre-turbo.

Looking at the exhaust manifold, I have identified an area that I think will be easy to drill, right on top of the manifold and back in the cylinder 6 running right where it meets with cylinder 5... I like this spot as I hear 6 tends to be the hottest, and being in the horizontal I can magnet / vacuum up any chips pretty easy.

Other locations I see recommended is the back half of the vertical portion just above the turbo and on top of the manifold again but up by cylinder 4.

For those who have done this, where did you guys install it, why, and after the fact are you happy with the location? Any reason you wish you would have put it somewhere else?

 

[AH64ID]

I have ran it in the 1-3 log and the 4-6 collector and prefer the collector for 4-6.

 

[Mathes308]

Had the same problem when installing mine, after tons of research and added self input, I build heat treat furnaces and install tons of TC's.
Seems the upper left side of the reinforcing rib at the turbo flange is best.

Here's the deal, what are you trying to save?
If you want to save the #6 piston, stick it right after the valve.
Most consensus is that the turbos exhaust turbine is the first to melt.
Therefore the combined exhaust entering the turbo is most important.

As a plus, if an injector becomes worn or starts to hang up and flow more fuel you will/may be able to tell with all the exhaust passing at or near the TC, with it on 6 only, the turbo or 1-5 cyls could be over heating and fail without warning.

Added note, increased timing makes Pistons hotter but exhaust cooler, retarded timing makes cooler Pistons but hotter exhaust.

Option 3, and 4

Two temp probes, monitor 6 and turbo inlet, or 7 probes and watch it all.

 

[Todd1113]

4-6 collector right above the turbo is where mine is too. Put a glob of grease on the drill bit and go easy it will catch the shavings.

 

[RVTRKN]

I installed mine where the "Y" is just above the turbo. It is easy, if you remove the fender liner on the pasenger side, and I used a right angle drill. I drilled, then just before penetration I slowly drilled through using a good vacuum, that my SIL held to get shavings. There are many methods used for preventing the shavings from getting in the turbo, but I chose a dry bit with a vacuum. In my search, and thread I started, someone advised against the grease method because there is a possibility of grease transferring to the manifold and allowing the shavings to stick inside, and worse than that they could stick on the turbo vanes in they got loose. Lucky for me, I did a test drill on a block of aluminum, and found that the EGT sensor was not 1/8" NPT, but was 1/8" British Parallel Pipe thread. I had to order the tap for the job.

 

[AH64ID]

Put a glob of grease on the drill bit and go easy it will catch the shavings.

I would not use grease. Grease will catch the shavings but on a warm bit, which it will be from drilling, the grease will lose its consistency and drop off inside the exhaust. Now you have grease/shavings in the turbo.

Without grease you will get some shavings in the turbo/exhaust but it's not a big deal because as soon as you start the motor they will blow out before the turbine gets to enough rpms to be damaged by the shavings.

With grease you might not get the grease/shavings thru the turbine until it is up to speed.

A dry bit on a cold exhaust is the best way to not damage anything.

 

[lpennock]

I always drill with it running. that way the exhaust blows the fragments out. Then let it cool and tap with grease to catch the tap shavings.

 

[AH64ID]

I always drill with it running. that way the exhaust blows the fragments out. Then let it cool and tap with grease to catch the tap shavings.

Where does the tip go if it breaks?

Also not all shavings will be blown out at the end and will get blown into a turbine that is at idle speed, which could do damage.

 

[lpennock]

Where does the tip go if it breaks?

Hangs up in the manifold wall metal like any broken bit does.

Also not all shavings will be blown out at the end and will get blown into a turbine that is at idle speed, which could do damage.

Don't agree with you on either count. Even if it does fall into the stream, the exhaust gas is going to carry it through the turbine. With the engine off it is going to lay in the housing to get caught between the blade and housing when the truck starts.

 

[RVTRKN]

Sorry, but that turbo is spinning at a high RPM even at idle, but to each his own.

 

[lpennock]

Only way to be 100% sure that no metal goes in the turbo is to pull the turbo.
1. Grease runs risk of fragments being caught on the inside that release when the engine is started and the grease melts.
2. Drilling with the engine running, runs the risk that fragments won't get blown out.
3. Letting the fragments fall to the inside puts fragments in the bottom of the housing to be hit by the turbine on startup.

If you don't want to pull the turbo, decide which method you think has the least risk and use it. Personally I would only use 1 or 2.

 

[AH64ID]

When the bit breaks determines where it goes, it may go in the manifold and it may go out of the manifold.

Shavings into the exhaust are NOT a big deal. Unless you place your probe in the turbine housing they will not fall into any turbine nooks and crannies and by the time they get to the turbine (vehicle off scenario) they are going with the flow and will blow right thru unless there is grease on them.

Hitting the turbine on startup is not a big deal as the rpms haven't reached idle rpm yet. If the turbo isn't removed the next best option is off/cold/dry.