flaattire
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« on: November 10, 2014, 05:44:03 AM »
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What range of EGT is acceptable for long term duty at high load, such as top speed runs or track use? The given hardware is a stock head 2.0 FSI BPY with K04 and 3" open downpipe. I installed a pyrometer in the leftmost exhaust runner in the manifold on my K04, and with stock BTS threshold, temperatures never exceed 1675F during pulls to redline in 4th and 5th gear. Is there room to safely run higher EGT in this situation, or would that not be suitable if the engine is to be run at continuous high load? Even if you don't deal with the FSI, your experience with EGTs in the sort of loads described is welcome.
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aef
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« Reply #1 on: November 10, 2014, 06:24:17 AM »
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Borg Warner Turbos are capable to run 1050° degree celsius.
Im Running my K04-064 with 950° via BTS.
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nyet
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« Reply #2 on: November 10, 2014, 11:27:45 AM »
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950-1000C
This is why coding out EGT sensors (e.g. in the 2.7t) isn't a good idea. Working EGT sensors are cheap insurance considering ..
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littco
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« Reply #3 on: November 14, 2014, 01:40:25 AM »
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Borg Warner Turbos are capable to run 1050° degree celsius.
Im Running my K04-064 with 950° via BTS.
Just to clarify this, they are capable of peaking for less than 2 seconds at 1050c, unsustained peak temps. If you ran them continuously at 1050 then they turbine blades would melt or at least start to feather.. You only ever want to see 1050 as a 1 off, if you are running that high then you need to get it looked into.. 950 is really the safe level you want to see these at.. |
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overspeed
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« Reply #4 on: November 14, 2014, 08:47:11 AM »
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Like one customer said one time: Better sorry than safe...  in MY opnion... Safe is about 880~900°C (for endurance users) for "normal" users 900~920°C But if you want to run "the last drop" then 950°C must be your target |
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ddillenger
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« Reply #5 on: November 14, 2014, 08:56:11 AM »
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Something people are failing to mention is that the EGT's seen in a 3rd gear WOT run are not representative of a 6th gear WOT run......
I have seen fools running 950 through 3rd. Log 4th and see what happens. Melted turbines.
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Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience!
Email/Google chat:
DDillenger84(at)gmail(dot)com
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kingkhalilz
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« Reply #6 on: December 05, 2014, 03:25:54 PM »
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Is EGT completely necessary?? With 14.7:1 Fuel should burn at the same temperature. If we put a bigger turbo and dump more fuel as long as the AFR stays the same so should the temperature correct??
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ddillenger
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« Reply #7 on: December 05, 2014, 04:31:34 PM »
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Is EGT completely necessary?? With 14.7:1 Fuel should burn at the same temperature. If we put a bigger turbo and dump more fuel as long as the AFR stays the same so should the temperature correct??
No. EGT's are heavily affected by knock. When the flame front doesn't propagate properly, temperatures skyrocket. |
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Please, ask all questions on the forums! Doing so will ensure the next person with the same issue gets the opportunity to learn from your experience!
Email/Google chat:
DDillenger84(at)gmail(dot)com
Email>PM
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nyet
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« Reply #8 on: December 05, 2014, 05:54:23 PM »
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It's actually even worse than that; timing retard (say, for knock reduction) will also increase EGT like crazy.
Lets put it this way: whatever energy isn't going into engine torque is going out the exhaust as HEAT.
Hell, guess how the EGT model works?
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kingkhalilz
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« Reply #9 on: December 05, 2014, 08:41:23 PM »
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I meant holding knock constant, we have sensors already for this. Assuming no knock. With afr constant just more fuel and air. This results in more power. Because a combustion engine is not 100% efficient this will create more heat because it makes more power. Or more waste because it put outs more. As nyet said timing retard also increases EGT. In order to run more boost and fuel timing naturally should be retarded for knock. This makes me believe EGT's are necessary because the temperature will be unknown and higher.
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Lost
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« Reply #10 on: December 06, 2014, 02:25:50 AM »
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So, what is the tuning receipt for long safe 6gear runs?
Less boost? More fuel? Timing???
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!nfern0
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Audi TT 1.8T BAM
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« Reply #11 on: December 06, 2014, 04:36:07 AM »
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So, what is the tuning receipt for long safe 6gear runs?
Less boost? More fuel? Timing???
OEM do it by more fuel. But they have test tracks for calibrating AFR. There you can go Vmax (=Pmax in most cases, apart from V-restriction to 250km/h or 210km/h (US)). There they start with a "safe"-look-up-table (out of engine test benches) and calibrate the AFR to values (for this load and RPM-point or area) where the exhaust gas is for example 950°C (depends on what the hardware is able to handle) or less. Then they add some safe factors for worse boundary conditions (hot air, hot engine and so on...). According to my experience there are always 30 to 40°C space to the temperature where it begins to harm your hardware, but this always depends on boundary conditions... Very important is, that in this temperature areas every 10°C is way more dangerous for your engine than most people think. The mechanical strength over temperature is decreasing rapidly at this temperatures. |
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« Reply #12 on: December 06, 2014, 06:31:05 AM »
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Interesting. I guess this does not apply on e85??
I am planing on doing high speed tune, BC next spring I am goona attend high speed rolling start race.
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!nfern0
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Audi TT 1.8T BAM
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« Reply #13 on: December 08, 2014, 10:08:03 AM »
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Interesting. I guess this does not apply on e85??
I am planing on doing high speed tune, BC next spring I am goona attend high speed rolling start race.
Unfortunately I don't have any experience regarding e85. e85 has for sure some main differences regarding knock and stoichiometry. -> Big influence on EGT by ZW and AFR... |
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Lost
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« Reply #14 on: December 08, 2014, 11:14:07 AM »
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Yup, EGTs are in 700degC range, so it should not be a problem.
On the other hand, there is a lot more boost and timing on the engine.
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