legacycentral bbs

I picked up a cool EGT gauge off of ebay last week for about $22.50 It is for a twin engine airplane so it has two temp probes and you just click back and forth a knob for either probe.

Here are my questions.

1- Should I install a probe in each exhaust header so I can compare left versus right head exhaust temps? While it may not be something that actually helps, it shouldnt hurt would it?

2- The wire lengths from the probes to the end of the wire, is somewhat short. Can I, and if I can, extend these wires to reach the gauge, and what type of wire do I need to use? Thanks.

I would suggest putting it as close in the header to cylinder #3 as you can get. Since that is the one that runs lean. Then put the other one in the other bank- so if you want a comparison, you have it.

As for the wiring, I guess it depends on how the guage works. My autometer one allowed me to cut and splice as needed. Some, the wiring it part of the probe, so you will just have to look at the setup and see what you think.

But it is a good measure of how the engine is running. Between that and the oil temp and vacuum/boost- I have a good idea of how sh'e doing.

most likely the instrument uses type T or type J thermocouples. These depend upon the current that flows between the junction of two dissimilar wires. You can add length to the sensors, at some small loss of accuracy. But, you will have to know the exact type of sensor (and thus wire), and get the polarity correct as well. And, you generally cannot solder the wires together since this gives a secondary effect. Overall it is best to have the correct length sensors to avoid problems. Find the info on the unit when you get it, call the copany and ask for an engineer. Armed with the right sensor type you can order the sensors in many different geometries and lead lengths. Again, watch the connector because if you attach it incorrectly you are screwed. Wondering how you plan to get the sensors into the exhaust pipe. Attaching it to the outside won't be very accurate.

The probes are set up so you drill a tiny hole and poke the probe in and a hose clamp sucks the probe tight into the exhaust

You could put one of the leads post turbo.

professor - Really? I don't think I've ever seen an EGT gauge that didn't use a type K.

Douglas - For what it's worth, on NASIOC several people have compared temperatures measured at the middle of the driver and passenger side cylinder banks and found that the driver side ran hotter. And apparently there's also a really good spot on the driver side manifold for installation of a probe; it's like a little flat button.

I agree it shouldn't hurt anything to put multiple probes in. Maybe put one right by the #3 runner and one in the middle of the driver side manifold?

William - Wouldn't post-turbo just be a really laggy and integrated signal? Cuz of the thermal mass of the turbocharger?

I don't think he can install it post turbo.

THAWA wrote:I don't think he can install it post turbo.

That be true!

I'd say put one probe in the #3 runner and the other over in the drivers side manifold like Vikash suggested.

I'm going to be installing my Autometer EGT here in a couple weeks when I install the 16G but I'm going to be putting it in my CES up-pipe because it's already bunged for it.

oops forgot about type K . that's higher temperature than the ones I use in my lab. in any case sensors with long leads or extensions should be cheap and easy to find. Just don't use speaker wire like some dolt did on a machine I fixed a few months back