Thread: EGT Limitation
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Old 17-04-2016, 09:44 PM
parmas parmas is offline
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Join Date: Jun 2013
Location: malta
Posts: 210
Default Re: EGT Limitation

Quote:
Originally Posted by mrx79 View Post
the turbine ar is a GT28RS 0.48ar on the T3 turbine housing.

I NEVER KNEW 0.48AR EXISTS. 0.64 USUALLY IS.

I'am seeing:

/wo WM: 898°C @ 8030rpm / 220kPa @ Lambda = 0,769
/w 50/50: 906°C @ 8065rpm / 221kPa @ Lambda = 0,776

950°C is my personal limit, but i would feel a bit better if i can keep it a bit lower then that.
Because i know that the material of my exhaust manifold is not rated for that kind of temperatures and i would like to avoid cracking. But up to now it hold's pretty well.

YOU ARE ALREADY ABOVE AND BEYOND MAX SAFE EGTS. MAX SAFE IS ABOUT 825/850degC

Also my goal for this year would be to run more in the region of 12:1 or 12.5:1 if possible afr, but then i would definitly be above 950°C.
Also i'am planing for more boost, when i've fixed my ignition misfire issue.

COULD BE THAT YOUR EGTS ARE SKYROCKET DUE TO MISFIRING AND BURNING FUEL INTO THE EXHAUST

What is your EGT limit?

I'am injecting 140cc constant 50/50 WM by weight.
This gives me a ratio of water to fuel of about 24%@4000rpm/200kPa falling to 8,6%@8000rpm/230kPa.

WHY ARE YOU DECREASING INJECTION TILL 8KRPM?

My question to the experienced guy's here: Is there anything with water injection which effects EGT's directly besides the normal "more advance, richer mixture" things which also are valid on a non-WM injected engine?

I thought about a second stage (for high rpm) of pure water at the TB or direct port inj. but this makes the setup much more complex and i would avoid any kind of unneccesary complexity.
I WOULD FOCUS ON SOLVING THE MISFIRING ISSUE.

COULD BE SPARK PLUG HEAT RANGE/ BAD FUEL ATOMISATION/TOO MUCH FUEL INJECTED/RETARDED TIMING/IGNITION SYSTEM FAULTY OR OVERHEATING COILS/DWELL TIME INCORRECTLY SET

POST SOME PICTURES OF YOUR PLUGS
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