So i ordered the adrenaline and love the power but my egt are in the 1300s and climb. I havent tapped the exhaust manifold yet because I dont have a clue if it is alright to tap it twice. I already have a pyro analog gauge and i want to keep it but i want to be able to use all the benifits the adrenaline has to offer. So my question"S" are can i tap it twice without takin a risk of weakining the manifold or is there another spot to tap it maby inbetween cylinders??

Thanks

 

Several on here have done so...I have too about 45 months ago with no issues...

 

I just took the pyro out & installed the Adrenaline pyro in its place, then tapped my mechanical gauge into the Adrenaline pyro with quick taps. It is working great & best of all both gauges read identical.

 

Don't use quick taps as that will cause a cold junction and introduce an error into the which ever reading comes through the taps. If the Adrenaline has the plug in connector instead of ring terminals then you would be better served putting in the second thermocouple.

On my set up the Isspro gauge and Edge Juice both use ring terminals as does the thermocouple. So on it I just have all 3 yellows and all 3 reds tied together at the rings and all is good.

 

I've had mine hooked up this way for a couple months now & no problems. Both gauges read identical. Having a hard time believing the "cold junction" theory.

 

Thermocouples work by generating a mV signal by the reaction of dissimilar metals. Unless your quick taps are Chromel and Alumel there will be an error equal to the ambient temp at the location of the taps.

FYI - it is not a theory!

 

I second what CA says... from some research I did last yr.on pyro probes. Interesting and complicated little devils.

I have had two manifold taps in the past (on two sides) and see no weakness issues/problems with doing it!

RJ

 

CA-- I think you are correct that quick-taps are a no-no. But I think your reasoning is incorrect.

The t-couples generate a small voltage through dissimilar metals. This voltage is traveling on the wiring back to the gauge. The gauge is calibrated to the resistance of the wiring length, because the voltage is so small that even the small resistance of the wiring can skew readings.

When a quick-tap is used, you are wiring another gauge in parallel to the first using the same probe. As we know parallel circuits have the same voltage at the branches. That's why JLent's guages are reading identically. THEY HAVE TO-- they are seeing the same exact voltages. The only variance would be in gauge calibration (though std calibration applies since K-type t-couples are universal).

The T-taps aren't changing the voltage at all. The dissimilar metals in that junction aren't arranged in a way where they can produce their own voltage with temp change.

So, it's the right conclusion for the wrong reason.

JMO

 

If I notice any problems, I'll hard wire them. I have aluminum quick taps on there now. I'm not saying that you are wrong, just haven't had any issues with my pyros at all & didn't want to cut the pyro wires.

 

You've been lucky Lent, and you probably have good enough connections that the difference has been minimal- possibly within tolerances for the gages.
Hohn is correct- and technically even splicing and soldering into the thermocouple probe leads is a no-no. You also have the issue of resistance in the circuit- the longer the wires or the poor connection (in the cold splice or a poor solder connection) can affect voltage values. Anything that effects the values of the leads from the probe to the gage can affect the accuracy of the said gage- thats why most reputable gage manufacturers will offer different length leads and tell you not to cut or modify the included leads.

I have some an electronics background- you think that sucks- when you get into radio frequency circuitry, especially high frequency you have to factor in the length of every wire and component lead because each affects the capacitance of the total circuit, so every chance means rechecking values of the circuit and adjusting component values.

 

I have 5 holes in my manifold. Two on the bottom. They are plugged from flipping the manifold. Two in the top have T/C's installed. One on the top is plugged because I am and idiot and drilled / tapped the hole in the precise location to interfere with the manifold bolt. That "Oopsie" did not make me too happy.

As far as JLent's set-up the "Cold Junction" concept explained above is valid. The most I ever see around here is two instrumentation circuits hooked to 1 T/C. That is typically only used for temporary periods of time. On the other hand what is working is working (for JLent).

Jim

 

Sorry guys but at the length of wire used in our trucks, resistance is a non factor unless it is gross (in the K ohm range). The reason the manufactures tell you not to cut or modify the wire is due to the fact you are likely to introduce a cold junction since you will not be using the correct terminals.

This link gives a great amount of very good information on the operation of thermocouples.

http://www.picotech.com/applications/thermocouple.html

 

Alright guys thanks for all the information I really appriciate it. I didnt want to take a risk of doing damage till i asked some people.

Thanks again
Tyler

 

Just a thought but what about having a pre-turbo and post turbo.

 

Has anyone ever put a pyro prope in the #6 runner in the manifold? I was thinking about doing this when I get an adrenaline since I already have a egt gauge and figured maybe it wouldn't be a bad idea since everyone seems to say that #6 gets the hottest anyways.