Looking at installing a pyrometer when i install the 16sq.cm turbo housing. Can anyone tell me if I should mount it pre or post turbo. I figured if I had the turbo off the filings would not go through it if i put it pre. Housing is here this week. Truck is a 92 d250 4x4 stock. Soon not going to be

 

Pre turbo is best.

 

Pre turbo vs. taking out as $10,000 motor. Post turbo is the only way to go, trust me, I spent the $10,000!!!!

 

There is about 200 degrees between the two. If it is pre turbo it shows hotter and you tend to lift your foot sooner. The pyro tells us we are overheating the turbo as well as softening the tops of our pistons.Every thing I have read say to put it in the manifold pre turbo.

 

Preturbo will tell you exactly whats coming out of the head and straight into the turbo. If its post, the reading will be pretty accurate on idle, but the more the turbo spools, the more the reading is off because the heat is converted to energy to spin the wheel. It can be off over 300 degrees with a spooled turbo.

 

Pre-turbo. That way you know how much heat you are throwing into the turbo. Who cares how hot it is coming out. Pre-turbo will also help you decide if your back pressures are getting too high.

 

i have mine post, but that is because at the time i didnt have a good enough bit or the time to drill the manifold, however post may be a bit better for the foot to lift off the throttle the fact is that you still know your egt's regardless of what some hard headed people tell you. this is also coming from an educated diesel mechanic(even though i dont tell everybody). if you have the resources i would go definately pre though.

 

Pre-turbo is the way to go.

 

Pre-turbo is way more accurate as far as cylinder temps go. It's the best for monitoring engine temps. The only downside to it is the turbo temps. Post turbo lets you know when your turbo is cooled down. I am more concerned about the actual temps in my motor under load. I do heavy towing with pod's, and want to know what is happening right now. I always let my egt's settle at 300 for at least 30 sec before shutting down, and have never had a problem with a turbo.

 

Thanks for all the input. Any suggestions on where to install it into the manifold and what kind of temps am I watching for. Thanks again.

 

You meant pre, right?

 

Ok, I know there's a story behind this and I'm sure I'm not the only one that wants to know.

 

Maybe the probe melted off and went through the turbo??? I have heard of this before, But I doubt that it would ruin an engine unless debris went through the intake side or something. Anyhow, if the probe melts off, maybe you should have been paying more attention to that pyro!

I went with pre-turbo without a second thought, because post-turbo readings are a joke.

 

Pay attention when you drill the hoe in the ex manifold, There is a web in the center, and if you drill into it, Well, you will have to drill another hole and weld the other shut, Just drill of to the side of the ex manifold just before the turbo flange, Look at the pics in the sticky, (i have a welded hole) oops! Otherwise easy install, I just drilled with a vac running next to the bit, and I tapped the hole with lots of bearing grease on the tap to hold the shavings, I didn't remove the turbo, and that was 30K miles ago.
Peter.