I'm guessing most of you run it before the turbo. I want to put mine pre-turbo in the manifold. I think welding the bung in cast iron you need to heat it up red and then weld. I don't have the facilities to do that. What I thought about doing was drilling the manifold and tapping it. That way I don't have to weld the bung in and I can thread the pyro probe right into the manifold? Any of you done it this way?
I dont think that you wanna be foolin with that, it gets very dangerous if that tip breaks. You can screw up the turbo send lots and lots of metal into your motor.
my .02
if you drill and tap, will it keep your probe in the middle 2/3rds of the manifold? if not then you you might have to have a bung.
i am not turbo'ed. but when I installed the pyro into my exhuast I noticed my probe was quite long. but I used the clamp and adjustable spacer on it. to get in the middle 2/3rds.
has anyone had a pyro probe tip break off? is this common? maybe if yur sitting at high temps all the time.
My pyro is drilled and tapped into the manifold right below the turbo intake. It's been there for about 2 years and nearly 100,000kM (a trip across the continent from west to east and north to south as well as many other trips in the Pacific Northwest). Here in Guatemala I'm often at a higher temperature than I'd like to be, probably because of altitude and steepness of the hills.
If it makes a difference, I'm running an Isspro brand pyrometer.
I work on diesel generators and the pyro's are most all located before the turbo in the manifold. I have yet to see a tip in the turbo or pass through one. And this on engines that have 16 pyros. I have seen some valves let loose and you could see the valve in the turbo through the glowing hot casing. The little bits of turbo never made it past the intake valve so I think you are pretty safe although drilling and tapping cast is a bitch.
On my Dodge Cummins, I drilled and tapped the manifold to get a good pre-turbo EGT reading. I have put MANY miles on that Dodge while towing heavy and I have no worries about the pyro probe failing. I can state emphatically that if you measure your temps post-turbo, you are kidding yourself. The CONSERVATIVE course of action is to measure where the temp is highest so that you know best when to get your foot out of the throttle. Some diesel freaks measure both pre and post turbo, and I can guarantee that if you do, you'll see just how drastically the temps drop due to expansion.
I'm going to try and dill and tap. I can always open up the hole and weld the bung if needed. Besides all these aftermarket turbos finding a stock manifold should be cheap and a piece of cake... right?
I have to wonder what everyone is trying to accomplish with the pyro placement. Where ever you place it creates the benchmark you use to tune and monitor your Toyota motor so why would anyone go to all the trouble to place it where it can cause the most damage if it fails. Does not compute...FWIW JM2C
Yeah.. but if your going to be on the high end of the scale alot of the time(probably like me at altitude) I'd rather have it pre turbo for a more accurate reading. If you don't know the difference in 2 readings pre and post a couple hundred degrees could be critical. At least that's my thinking.
My buddy that runs a turned up cummins (by a previous cummins exhaust engineer) was told not to go 1000* post turbo. Now I realize it's totally different but he probably knew it's ~200 degree difference. or something like that.
You monitor EGT to know when the devil to get your foot out of the throttle. It is a preventative measure so as to enable you to be ahead of the damage curve. If you don't know what the temps are pre-turbo, you'll be too late to prevent disaster. You are only guessing what the temp drop is through the turbo. Each turbo expands the exhaust differently, and I am not going to play that guesswork game. A question for those who are pre-turbo phobic: Have you ever known anyone to suffer a broken pyro? I haven't, and I know plenty of folks who have pyro's pre-turbo. Talk to truckers sometime and then you'll see.
Wayne,
What brand of pyrometer disintegrated on you (AutoMeter, Isspro or ???)? I'm just curious if it was a poor quality issue, a freak failure or something else.
Personally, I'm with dieseldog. I want to KNOW what's going on inside the engine where damage due to heat can cause problems. I'm not too worried about what might be the case somewhere in the exhaust. I know when my intake hose blew off a few weeks ago the temps shot up to well over 1200F, I'd guess 1400 or more, pre-turbo. That's the information that I want from my pyrometer
This topic is almost to the point of nauseation. It is totally retarded(backwards thinking) to put the pyro after the turbo. The exhaust after the turbo is not even under pressure. To get an accurate/proper reading you must take into account the heat generated by the pressure in the manifold. Is the temp after the turbo going to tell you that your valves are burning to bits. I think not.
Do it right or save the money for something else. As it has been said before they don't break very often. Usually only do to P.I.F. (pre installation failure) because some hack was beating on the darn thing.
DO IT RIGHT!!!!!!!!!!!!!!!!!!
Wayne,
What brand of pyrometer disintegrated on you (AutoMeter, Isspro or ???)? I'm just curious if it was a poor quality issue, a freak failure or something else.
it was an autometer, these are the only gauges i run.
no one knows why it broke off.
i am going to check with Herb and see if his quit or broke off. i know he was in Mopac replacing his sensor the same time i was...
cheers
it was an autometer, these are the only gauges i run.
no one knows why it broke off.
i am going to check with Herb and see if his quit or broke off. i know he was in Mopac replacing his sensor the same time i was...
cheers
Well that makes me a little more comfortable. Mine is an Isspro as is the one in my daughters FJ55/3B. That's not to say that AutoMeter is crap because it likely isn't, I just liked the colour coding on the Isspro pyro gauge and the lack of vacuum reading (pointless on a diesel) on the Isspro boost gauge.
Does ANYONE have ANY experience with Isspro pyrometer probes failing by breaking off as described by Wayne?
Not the wires, the gauge face is color coded, green up to about 900, yellow from 900 to about 1250 and red over 1250. All you need is a quick glance to see if you are in or approaching the red area and need to back out of the throttle.
I think they were a little more than the Autometer gauges when I got them for my kids FJ55 but not much. Cory from Kodiak got them with my AXT kit for my truck.
i see, nope these are all black.
sounds like a nice gauge and that could be a nice feature, what i look for is the needle straight up? ooops time to start backing off...
cheers
I wonder if anyone running a post turbo pyro has burn up a motor. I bet NOT so 6 of one half dozen of another. I say what ever floats your boat as long as you run one
