Car in sig is fully tuned, just installed an autometer EGT into the 3rd runner of the turbo manifold, about 1.5" from the head. The readings are as follows in F.

Idling = 950-1050

15 ingh cruise = 1250 - 1350

10 inhg cruise = 1400 - 1520

1-2-3-4 WOT = 1600 by the end of the run.

I have done as much research as I could, and find that these numbers are pretty high in comparison, but find usually that people are mounting their probe either in their collector, or just after the turbo, which has to be at least 100 deg difference right?

Any input is greatly appreciated!

 

them numbers seem fine.. i wouldnt take it over 1600 tho. thats pushing it. i use to have mine right at the head as well and read basically the same.

 

I think the Melting Point of AL is around 1220deg, but that is from a raw flame over an extended period of time and its not being cooled by Fuel and Air, I think 1600deg is pretty hot but I cant remember what mine use to be to compare, I know it went down a few hundred degrees across the board almost when I switched to E85.

 

I wouldn't mount that probe in the manifold what if it melts or brakes off bye bye turbo.

 

from what I have read, mounting it post turbo makes it completely useless...

 

They are designed to be mounted on the manifold, so they wont melt..... and if they do other things inside your motor are melting as well.

If you have a screen or filter over your Turbo like your supposed to nothing will get ingested in the even for some freak reason it does break off.

 

I agree, the probes are made to withstand the heat.

but.. screen on the turbine side? I think your getting things confused

 

yea I just realised I didnt even consider the very tip of the probe end breaking off into the manifold, I was thinking he meant the external part of the probe being ingested into the Compressor.....

This is unlikely to happen either way.......

 

1600 is hot, you have to much to to little timing and causing high egt's. you want to stay around 1400 during pulls tops 1600 but thats really pushing it. not good for the turbo either

 

I used to have really high EGTs as well when I was boosted. 1600+ deg. by the end of the run. I think that is because I had reached MBT ( or mean brake trq.) I tried adjusting timing each way and did not see any difference in EGTs. Some people say that that temp. is high, and from what I have read it is rather high. However, I ran my setup this way for about 15k without any problems before I sold my car. Watch for knock and keep an eye on your AFRs.... I wonder if running meth injection would make any difference? In for more results and someone with more knowledge about this subject.

Edit- I only pulled 2 degrees each way from 5.8k- to 7.2k. I suppose I should have done it to the entire boost map each way to see an actual difference in exh. temps across the powerband instead of trying to make such a linear change and expecting better results.

Edit- 2 My probe was about 1in from the head in runner #3.

 

I wanna say in the world of Subaru's (I was reading about wrx's in particular), 1400-1500 was hot. Someone was making a claim that subaru should have been giving out free reflashes to owners since these numbers were being made when the car was completely stock. Something about a delayed response from the ECU when going WOT. They said the timing was fine but it was a fuel issue from said delayed response.

 

Oh and the best spot to mount the egt probe is as close to the head as possible to get the hottest reading. Sorry to double post

 

The subaru issue is leaning out... (they've already had to reflash my legacy and replace both cats and o2's)

this sounds more like an ignition timing problem...

 

and preferably in cylinder 4 or 3 as they run the hottest

 

im running 50/50

 

Exactly. More lean = more hot

 

I guess the next question would be what is fully tuned? ANy idea what AFR's the tuner settled for? For lighter loads, 12.5:1 can work fine, but for lots of power, 11:1 may be needed. It's generally up to the tuner to make that call, but it seems like he never saw your EGT's.

 

^^ In rotaries, EGTs get to almost 2000 degrees, near the melting point of the metal. EGT reading deal more with the correlation of exhaust gas radiant heat, A/F and timing, all at once. When using an EGT gauge, it needs to be tapped to the leanest cylinder (in Honda's case Cyl #2) in the manifold. With that said, it is rather normal if it is tapped into the manifold to see 1400 degrees on simple highway driving and up to about 1600 degrees on most WOT pulls on the highway. having a relatively high EGT also means that ignition timing may be a bit lean (as stated) but it also means that you may have the wrong heat range of plug (Maybe you have a 6 range instead of 7 for example on a BKRE series.) It also could mean that the exhaust housing is experience quite a bit of backpressure, in which a larger turbine housing may need to be used based upon your power goal.

How do you know the difference you ask? Well, before widebands were commonly sold to the public almost 10 years ago, EGT gauges were what was used to help determine issues that were going on with the combustion process. When EGT readings were high, it was more of a process of elimination in which if timing, plugs, A/F was ok, the issue would more than likely be backpressure (or some variant).

Many people now just datalog their tunes and get different widebands in order to answer these questions now. Really only us old schoolers and DSMers use Pyrometer (EGT) gauges, because that is what we were most comfortable with. I myself had several 500whp + turbo hondas and 4G63s and never once had a wideband attached to it after the tune. Still don't. I like EGT gauges, because to me they were a bit more effective and preventative, because you knew what could be wrong long before the problem could get to a point where the wideband reading was so important. But again, that's just me.