Author Topic: Splicing EGT Sensors...  (Read 8287 times)

Offline jonboy

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Splicing EGT Sensors...
« on: May 10, 2007, 08:35:09 pm »
Hiya :)

Some of you may recognise my nick from the SXOC.. ;) I've been pestering phatbob over there about VEMS for a week or so, after getting the lowdown from Jez a while back - it's probably going to be going into a turbo'd MX5, which is currently running on an emanage, with larger injectors etc etc... Bob's asked me to join and ask questions on here, for the greater good :)

So - currently I've got a defi link meter, with boost, oil, water and egt sensors. As far as I know, the defi uses a standard EGT probe - my question is will I have to get the manifold tapped again for a VEMS egt sensor, or can I tap into the wiring before it hits the defi control unit, and use the existing sensor? The logical part of me says as long as the sensors are the same, it should be possible :)

Anyone tried it? :)

Offline rob@vems.co.uk

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Re: Splicing EGT Sensors...
« Reply #1 on: May 10, 2007, 08:57:04 pm »
The thing with EGT sensors is that they actually kick out a voltage dependent on temperature, in the order of a few millivolts, so splitting it between two sensors may possibly cause an issue with the voltage not being quite right...

You can calibrate the sensor through the VEMS but I dont know about the Defi gauge as thats a black-box as far as I am concerned.

Cheers

Rob

Offline jonboy

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Re: Splicing EGT Sensors...
« Reply #2 on: May 10, 2007, 09:17:10 pm »
The thing with EGT sensors is that they actually kick out a voltage dependent on temperature, in the order of a few millivolts, so splitting it between two sensors may possibly cause an issue with the voltage not being quite right...

You can calibrate the sensor through the VEMS but I dont know about the Defi gauge as thats a black-box as far as I am concerned.

OK - fair enough :) You can't callibrate the defi as far as I am aware... Would it be possible to use a programmable output to 'fake' a sensor, in much the same way as you can with most WB o2 controllers, for the defi?

I'd rather not have two holes in the manifold if I can really help it ;)

Cheers,

Jon

Offline rob@vems.co.uk

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Re: Splicing EGT Sensors...
« Reply #3 on: May 10, 2007, 10:15:36 pm »
I doubt it, the variation in voltage output between 100 and a 1000degC is tiny simulating it is likely to be problematic.