lejams

The burnt valve was on #4 and all else was well on #4. After lifting the head and expecting to find damage only on #4, we discovered the piston & cylinder damage on #1 with the valve in tact, thus the unexpected surprise.

lejams

The thing is if something goes wrong, ex. injector failure, wiring failure... what gaurantee is the default then? One of the other cylinders heats up - like what happened to my engine, no data and bam - rebuild $$

Your not alone, of course its all gotta match!

lejams

For starters this looks interesting:
E-4 Four Probe EGT
[URL=http://www.aircraftspruce.com/catalog/inpages/ei_egt.php]

lejams

These engine scanners are expensive but seem like they would be the best/most sophisticated monitoring devices we could ask for. Does anybody see why they could not be used on automobile engines?

Chances are very good that one of these devices, particularly one that constantly scans and gives an audible alarm warning, probably would have thwarted my engine failure. I plan on looking much further into this.

I know the 951 can fly, I guess it just needs the instrumentation to keep it air worthy (-:

MySwiss

You can't get much better instruments then the ones they use on air planes (FAA certified). There is no reason why these instruments could not be used on our cars ,cause there are lots off turbo charged planes out there.

dand86951

They will work as long as you get a 14 volt system. Some aircraft thermocouples have a bit slower reaction time as they are designed with thick walls for long life and most aircraft engines operate in a narrow rpm band so quick response is not as critical. The JPI units have data logging in some of their units but they are expensive. Call the manufacturers and tell them what you want.

By the way a lot of aircraft come from the factory with only one probe and on turbocharged engines it is usually prior to the turbo, thus it really is a turbine inlet temperature and not a true exhaust gas temp. When each cylinder is measured the placement is usually about an inch, at least, away from the exhaust port.

eastendr

I use an autometer probe about 8" from the port, in one pipe. This feeds both an Autoneter 2" gauge and an HKS CAMP digital display & datalogger.

Typical temperatures are about 1000f at adle and maxing out about 1550f under boost. Any more than that and it gets expensive !

I've just changed my air fuel gauge from K&N to one of the Link gauges from Danno which is more accurate.

At the moment, it's sharing the standard (narrow band) lambda probe. When I change the turbo I'm going to fit a separate wide band sensor.

I also monitor charge air temperature.

Look on my site, 944 turbo page 17 & 11 and you can see the setup.

Rick.

Mike S

I agree with everything Tony has said so far. However, I mounted mine in the just ahead of the cat using the little crimped off test port. At that location I'm seeing 1500-1540F at 12:1 ration under full throttle. That seems a bit hotter than what Tony's seeing in the exhaust port which lends itself to the milledge explanation of unburnt fuel. In any case, once you establish a baseline temp and corresponding air/fuel range you can keep an eye on your engine pretty easily.

86944turbo

What do you do when EGT #'s scarry? Me, I close my glove box, after turning off that pesky buzzer that comes on @ 900C. Bad sensor, I guess. They wear out quick. Diff. locations and diff. mfgs. read diff. Right before turbo is probably the hotest spot in ex. They are good for relative comparisons. Seriously though, what does one do when high ex. temps are displayed. Add fuel? Lower boost (perish the thought). Larger I/C? What's high?

Ahmet

I was in a 350whp WRX a few hours ago (I assume that's around 400 crank). He would have the egt around 900 peak after two stints 110-0 back to back. His idle was around 400 to high 380s if I remember correctly. That's out of 2 liters on 93 octane gas btw. The sensor was mounted right past the collector. Ofcourse this is entirely useless information, except to maybe get a vague idea of what to expect. This was on a greddy gauge (and sensor from what he said).
Ahmet

Mike S

To lower temps you generally want to add some fuel to the mixture. However, our cars seem to run a bit hotter than most of the other ones I've seen. Normal under full boost is 1400F-1550F(1550F when I'm on it for extended periods of time) in my car. That's with a stock turbo at 12:1 fuel ratio.

TonyG

My car idles around 1100F.

A lot depends on cam timing, cam overlap (lobe centerline), ignition settings, and the amount of fuel.

toddk911

MICROFLIGHT EGT
Includes probe

2-1/4", 600-1700°F
P/N EG004 $64.000


Seems like a good price as it includes guage and probe.

Ben Z.

I'm not an expert on this kind of thing, but the sensors are just thermocouples, right? If so, then maybe you could just rig up four of them to a switch. I think thermocouple measurements don't rely on the resistance of the wire, but rather the voltage that is generated because of the difference in temperature between two junctions (first one in exhaust stream, second one at ambient temp) of dissimilar metals. I'm not planning on doing this, but it is something to think about.

dand86951

lejams, the EDM - 700 egt system at

http://www.aircraftspruce.com/catalo...700egt_cht.php

will do everything you want and data log it to a PC. Very expensive but if you want to monitor engine egt on each cylinder plus things like intercooler temp or oil temp and have it display in one gauge it is one of the best on the market in the aircraft industry. The probes are top quality along with the rest of the system.