EGT - Before or after the turbo?

[Worm Drowner]

Well, I'm about to install a pyro on my truck and asked the most trusted source I know, my dad. He just retired after 50 years of working for Cat dealers (Ohio Machinery, Alban & Mustang). He told me point blank to put it between the manifold and the turbo.

[99Smokin73Stroker]

Awesome thanks for the info! Man, sooner or later i'll have the money and i'll get these darn things in!

[Ramsmoker]

My family has been in the heavyhaul trucking biz for over 50 years and none of our Cat or Cummins engines in the last 35 have had the thermocouple in the manifold. The only engines I have seen that do have the thermocouple in the manifold are noncycleing engines like boats, gensets, dozers and scrapers. Your reading will only be as accurate as your gauge calibration. I don't know if you can get a set that is calibrated for the manifold. I think you will be around 200 degrees warmer in the manifold. To be honest, and I know this from my biz is that it doesn't what kind of gauges you have, how many or how there hooked up. If your not in tune with your rig, your the one to blame for the problem. I don't mean to sound harsh but you wouldn't believe the excuses I have heard over the years of why the engine melted down or why the connecting rod sawed the block in half. Some of the major trucking fleets in the US know this and don't even get extra gauges. The bottom line here is to know your rig's limits and stay under them.

[99Smokin73Stroker]

That may be true....but I don't think you were running to your local diesel shop to have a chip burnt to add 150+ horsepower, stacking chip upon chip, stuffing 100+hp injectors, searching for highest flow intakes and exhausts, throwing on propane and nitrous and anything that'll make your dump truck faster than brand x's dump truck! Those big ol engines were designed for that work and heavy hauling. Our smaller light truck diesels were designed for what they advertise them to do on tv which is pull our horse trailers and fifth wheels and the heavier loads that gas trucks have a hard time with.....so it's only natural we should keep a lookout when we go adding all the freakin horsepower we do...

[Fis Teck]

On Cat engines where you have a manifold befor the turbo where there is room, that is the best place. On the V8 diesels Ford and Gm post is the best place, so you can read both banks. On the Dodge with the cummins some have a split exhaust on the outlet and you can only read the back three or the frount three so post is still the best spot.

[99Smokin73Stroker]

But on the v-8s I mean really, just how much difference is their going to be from one bank and the other? Are we really talking a huge difference, or just a few degrees?! I'm just going to put my pyro where I please, there's too many dog gone mixed up "expert" opinions going on in here! I feel like i'm drunk with all this!

[Ramsmoker]

Hey stroker, How wrong you are. I have my big haulers running 700hp on the floor. I don't have any warranty but the Cat house knows what I'm up against every day. This engines are cranked up!!! Cat has the software on a laptop. Westrap the truck down on the rollers and tweek away. There are a couple small shops around L.A. that will build and warranty 950hp on the floor engines. I have had many many hours in the dyno room with my trucks. I was suprised you asked about dual pyro's. Fastest way I can think of to catch a problem. My drag has three temp senders, one in each head and one at the front of the engine. Like I said before, I'm not trying to be harsh or be a know it all. My point is to get good gauges, know what is the norm and limit for you rig and pay attention. There are sounds, smells,vibrations and roughness that can be a sign to get off the juice. Your pyro brand and mounting location is not going to save the day.

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Last edited by Ramsmoker : 11-16-2005 at 11:19 PM.

[Mike OB]

I took out the exhaust pipe that goes between the turbo and the exhaust manifold on the left side. Then I welded a nut on the pipe and drilled it out so I could tap it to the right size. My egt sensor is just over the trans and out of harms way. It made installation a lot easier Mike OB

[nsrchofpwr]

my banks 4" downpipe has a place on it right after the turbo. why is that?

[Marty]

Because some people put their egt gauge post turbo. It's alot more inaccurate and I wouldn't do it.