Turbo Temperature Probe Install Location

[MearCat]

I have made a custom temperature gauge to show ambient, intake, oil and turbo temps. I have installed the ambient probe in the bumper area, intake probe right before the throttle body, oil probe in a filter sandwich plate but not sure on the turbo probe. I have the option of either having a probe that is mounted into the upper dump pipe right next to the flange (measures exhaust gas temp), or a thermocouple washer that is bolted directly onto the turbo exhaust flange (measures the turbo housing temp). Any opinions on which would be better? and why? The speed of the response of either thermocouple is very fast.

I have attached a pic for those who want to see the custom gauge.

[Busky2k]

EGTs measured after the turbo are almost meaningless because you don't know the real EGTs at the exhaust valve.

Put one into the turbo manifold, thats a good spot!

[R33S2]

Did you make that yourself or is it a shelf product?

[MearCat]

I should have said this before - I will not be putting the EGT probe before the turbo as I'm not willing to pull the turbo and manifold off to fit a temperature probe.

R33S2 - yeah - I designed and made it myself. There's a bit of circuitry and programming behind it though.

[ODessA]

dude that thing is sweet u could make a fortune !!

[carl h]

like busky2k said if its not near the head its worthless as the gasses have cooled significantly...

pulling the turbo isnt that hard of a job and besides gives a good excuse to drop in an uprated elbow .

[Bass Junky]

MearCat.

Check PM.

[discopotato03]

Yes you want to know the EGT out of the engine not the turbo for the reading to have any real significance . If it is the washer type thermocouple you may be able to fit it behind a turbine housing mounting nut though put another washer between it and the nut .

Is the oxygen sensor in the exhaust manifold or turbine housing with RB engines ?

Cheers A .

[MearCat]

The O2 sensor in the RB's are in the (dump) pipe straight after the turbo exhast housing - as is the case in most cars I would say.

[R33S2]

Could you do something like that in a Tacho, boost, speed etc?

The reason I ask is I've got the microtech Hand controller but the readout is small and I cant monitor just one without all the others, if you know the handset it displays upto 6 or so at once flashing to another 4 other ones.

Or post a link to a DYI?

[Roy]

So this is the same one as in a magazine about 6 yrs ago? A guy with a CA18DET S13 made one up...or is it different? Either way, it looks cool...i have most the parts to make one stashed in a box somewhere..only i couldnt get my hands on the software as the guys email address changed just before i was abotu to build it. So if its the same one id love to get my hands on the software...mind

[MearCat]

A guy by the name of Martin had something similar fitted to his 180SX more than a couple years ago yeah, but he had boost, battery voltage, oil temp & EGT. I designed mine specifically for temperatures only because I already have a boost gauge. I used a PICAXE chip in my design and like Martin, will not be publically releasing the source code or entire design for it- Sorry!. If it was a small project that took a day then I'd release details but I've put way too many hours (upwards of 100+ hrs) into the design/construction/coding it to give it away for free.

Will I look into selling them as a kit? - maybe, but I've got other higher priorities in the coming months.

[Sydneykid]

At idle and low rpm’s there is some difference in the EGT’s in the primary pipes, as close as you can get to the valve practically, compared to the EGT’s at the turbine outlet. But as the rpm and exhaust flow increases, the temperature drop becomes negligible. The only reason we measure EGT’s at the primary pipes is to pick differences between cylinders.

Keeping the above in mind, I would place the EGT sensor behind the lambda sensor in the dump pipe. That ensures it doesn’t mask the signal to the lambda sensor.

cheers

[MearCat]

Which would be more useful? - a probe in the exhuast gas flow (EGT) or a probe ON the turbo itself?

[Bass Junky]

I would say probe in the exhaust gas.

A prone on the turbo itself would not be anywhere near as effective.

the lag between a high temperature event in the gas and a reaction of equal magnitude on the turbo itself would be no good.

[MearCat]

Mmm - could the temperature reading from a probe in the exhaust gas be used to accurately determine when to turn the car off after a hard run? Or is "turning the turbo off when it's hot is bad" a myth?

[Sydneykid]

Certainly turning off a hot, plain bearing, oil cooled turbo is a very bad idea. Not quite so bad with a ball bearing, water cooled turbo, but still not a good idea.

What you really need to determine if the turbo is cool enough to turn off is the core temperature. Which is neither the turbine cover temperature or the EGT.

If you have turbo blanket, ceramic coating or wrapping on the dump pipe, I suspect that either turbine cover temperature or the EGT would give you solid indication of what is likely to happen to the core temperature when you turn the engine off.

cheers

[Roy]

. I used a PICAXE chip in my design and like Martin, will not be publically releasing the source code or entire design for it- Sorry!. If it was a small project that took a day then I'd release details but I've put way too many hours (upwards of 100+ hrs) into the design/construction/coding it to give it away for free.

Hairy muff

I eneded up buying a data logger anyway...but would be good to have a few more channels to montior various temps, instead of having to swap over sensors when i change things

[PHATR32]

hey i designed and built a weather station a few years back using a pic.

it mesured temp, humidity, wind direction and speed.

i can easily change the senors and programming to work with reading automotive signals etc, if there enough interest.

steve

[R33S2]

Im interested