Engine/Transmission (1994 - 1998) pyro probe placement

[dlefebvre]

with the addition of the fuel plate and soon to be added 3k gsk, I want to install a pyro. I know the best place to install it is in the manifold just before the turbo, but has anyone done it after in the pipe? Was thinking of this just for ease of installation. I have seen the other thread about this regarding removing the turbo versus doing the install in the truck. Are they accurate after the turbo? Thanks in advance fellas.



Dean

 

[DSutton]

The pyro in the pipe will not be as responsive, and will be at least 200 degrees cooler. Lots of folks have them there, they just know their max EGT is 1100 vs 1300 pre turbo.

 

[bmoeller]

I put mine pre because I wanted to know, not guess, what the temps really were. Also drilling and tapping was eaiser. It reacts as fast or faster to changes as does the boost gauge.



One of the semis that I drive came with a pyro (can't talk the boss into putting 1 in the other truck). It had been installed in the factory location that is about 2-3" after turbo. The gauge response is very slow. I won't let it get over 900-950*. The only time it moves FAST is when the hump hose gets blown off and lose boost.

 

[wsmalley]

easy install post turbo???

If you think that would be easier to install it there, remember that the downpipe is back under the cowling so have fun with your drill. Also, if you plan on buying a 4-inch exhaust at some point or eventually moving to an HX-40 or something similar(you know you will, if you say no just remember that all of us here at several points said we were done BOMBing ) you will be buying yet ANOTHER downpipe and have to redrill yet again. I say drill once in the manifold and be done with it. One drilling versus 2+ drillings. JMHO



Will

 

[dlefebvre]

Thanks guys, whenever I think about the turbo on that side of the engine compartment, I get a mental picture of my 91 where everything is in the open and easy to get at. Trying to adjust to the "new" 95 May as well take the extra time and do it right.



Thanks again



Dean

 

[mchelius]

Has anybody ever lost a turbo from a (pre turbo) probe failure? If so how long did it last before it failed? Does anybody check there's on a regular basis? Just wondering.

 

[illflem]

mchelius, your question has been asked several times here and the subject of at least one poll, as far as I know not one person has reported a turbo damaging probe failure. By the time the temps get high enough to destroy the probe your turbo will be the least of your concerns.

 

[drrhoades]

Could someone post a picture of exactly where the pyro is pre turbo. As I understand in 2 - 3 inches in front of the turbo.

correct me if I'm wrong.



Thanks

Doug

 

[illflem]

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[drrhoades]

Thanks for the picture like they say a picture is worth a thousand words. That clears up everything.



Doug

 

[Bseg]

Would it matter if the pyro was placed farther back on the manifold where the plate covers the EGR outlet? This would probably only be closer to the two rear ports and it seems the only disadvantage would be that you are monitoring the exhaust temp of those only. Doesn't seem that the temp should vary by that much. Anyone have an opinion on this?