the only thing egts are good for is to keep your turbo alive. Egt before the turbine needs to be about 900C max (under full boost/WOT)(like any other turbomachine). That is the max temp the turbine wheel can take reliably and not fatigue/fail.

 

That is absolutely false info.

The 900*C estimate is based on the theory that on pump gas if you are eclipsing 900*C, then you are at or near the point that knock is occuring and timing retard is raising the EGTs.

Turbos can reach extreme temps of 1800-2000F.

EGT's have almost nothing to do with turbos lifespan, but more to do with preserving pistons if anything.

 

TTP, you were saying not to even look at peak as it means very little, but then you are saying that my peak is most likely reading correctly. IF these temps i am seeing are correct, then why shouldn't i be worried?

let me remind you that when i received these temps, my car was never at WOT the entire drive.


my brother gave me his old thinkpad but i had to order a new battery. when it comes in i'll start datalogging and see what's going on.

 

1. Turn your oven to 450*F.
2. Beep, beep, beep- preheated.
3. Open door
4. Insert hand for 2 sec.
5. Remove hand from oven
Get burned?

6. Insert hand in oven for 12 sec. (or until you can't take it anymore)
7. Remove hand from oven
Now how does that feel?

Both tests are done at the SAME peak OGT

Peak OGT / Sustained OGT (Oven Gas Temperature)

 

understood. again, i'll have to see what the logs show me once i get this laptop hooked up. thanks for taking the time to reply to my posts.

 

Again, EGT's are a STUPID STUPID tuning tool. Wideband o2+Timing logger = the win :P. Reason I reiterate tuning by EGT's is dumb is simply because of the fact that you can be running really lean or really rich and show signs of "danger" (upwards of 900c). You have no idea whether you're lean or rich until you have access to a wideband o2 and/or a timing logger. Also remember some cars like it a bit rich and some a bit lean depending on where they make their most power/tq. The "general rule" of under 900c is just that, general, don't take it to heart while tuning because it may be completely false in reality on your own particular vehicle. A/F's around 11.0-11.5:1 on 91/93 octane is a "general" aim on daily driven vehicles while trying to retain safety; some tune for closer to 12.0:1, either those who run n/a cars or those who like extracting most hp while leaving little space for fluctuation in ambient temps, etc, I dont like pushing my own vehicles that far. That being said, stop trusting your EGT's so much and go buy yourself a wideband.

 

are you talking to me, cuz i already have a wideband. i mentioned it in my earlier post that my A/F was at 10.5.

 

I don't know what you are really looking for with EGT's but aluminum will melt at 1220.4*F.
Here is a link to a chart for melting points .

 

I don't know why nothing was said about this. That tip had to pass through your turbo to get out. I really doubt that it would go through without hitting an impeller. With luck it didn't do any damage, I would think by now you would have noticed if it knocked it out of ballance. At over 100,000 rpm, a little out of ballance will make a bunch of noise.

 

too rich also 'cause the EGT to rise. i myself sometime peak at 930c. but you want to to be like 850-860celsius range because if you were going up hill at WOT your EGT will higher than WOT on the flat ground. Load play a factor. So anyone who running above 900c throughout the rpm range, is lying. unless you running some cheap *** EGT gauge or drag your car "wow my car is fast, but it's ***".

 

i dont remember hearing or feeling anything.

 

Also poor advice for WOT tuning. 850-860C is making little power and way conservative. Cruising partial throttle EGT's are in this range and are normal.

 

TTP you obviously know nothing about turbomachines. Im just here to help. I used to have a job with an OEM engine MFG and I did alot of engine mapping and this is the way we mapped our engines. 900C is the number for production reliability, a turbo can go higher for racing but its life is reduced considerably as you go higher than that.

 

Yes, 9 4g63's, 10yrs experience... Nothing at all...

900c "OEM reliability". If we wanted to keep our Evo's stock at 10.5a/f and 850-900c EGT then there would be no need for evolutionm.net.

We drive domesticated rally cars with performance that rivals 6-figure exotics. They are racecars, period. Any car that costs $500+ just for stock brake pads and $1200 for stock tires every year may be in this realm of performance.

How many blown stock turbo's from overheating have we seen on evom? I know of one... Buschur's modified TME-20g. God only knows how much boost and rpms that thing spun at but it is unlikely that it blew due to EGT.

 

An accurate, fast responding, properly installed EGT gauge can be a very usefull device. If what you meant to say is you shouldn't tune air/fuel with an EGT gauge alone, that is true. I recommend using a wideband and EGT gauge in concert.

During tuning as you turn up the boost, EGT's are a great indicator of when your system's efficiency is falling off. This way you can stop before knock or power loss on the dyno appear if absolute maximum power output is not your goal as with all street cars.

EGT gauges are also a great warning device after a car has been tuned. They don't pinpoint problems by themself, but several different types of issues will generate high EGTs. Some examples are vacuum and/or charge pipe leaks, overboost, detonation/pre-ignition. (Leaks and overboost conditions result in the turbo being over-spun generating extra heat)