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Hi guys,

Been doing some data logging on my g4x, and noticed something slightly odd. My EGT's are always between 780-800C. This is at idle as well. I did some pulls, and noticed the EGT's to be the same, or very similLog.thumb.PNG.27b0871294536066c3a896a558709a46.PNGar. Havent seen it go over 800 so far, mind you I only went for a drive yday after updating my logging params.

I dont think that's right. Even at idle. I am having high ECT at idle, and I have just upgraded my AC fan to a Maradyne 14inch fan that pulls 2100~CFM, and it still has a very hard time controlling ECT when set to 85C.

 

What sort of EGT's do you guys see? I've had a look at my fuel and ign maps, and I dont see lot of fuel added, and not much timing either. Only 13.5~ at WOT.

 

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Thanks guys, 

 

@Ben C34 - Yes, its at the lambda - So I guess i can disregard my readings then. I have a spare bung, so I can throw in a EGT sensor/amp then.

 

@GTSBoy - Do you have a beanie on? What turbo if you dont mind me asking? My turbo gets very hot, iron exhaust housing, and its a top mount too, so prolly explains a little.

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Stock 25 Neo turbo. Was same when the previous engine was RB20 with stock turbo. All on stock manifolds. I have drilled the turbine housing(s) just downstream of the inlet flange.

No beanie - just all stock heat shields. FWIW, I don't think the presence or absence of insulation on the outside will change the gas temperature to an extent that you could measure in that location anyway. Even if it changed it by 20°C, you see more variation than that just in normal usage anyway. You'd have to back to back it very carefully to be able to tell.

If you are planning on measuring DS of the turbo, you will get different temperatures that I get at the inlet. The expansion of the gas across the turbine extracts energy, so you have lower P & T according to how much work is taken out. Plus heat losses off the turbine housing and dump, subject to my thoughts on that above.

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I feel these days (my personal opinion, please DYOR), especially with most of these cars on E85 that single channel EGTs are not as important as measuring EMAP / TIP.

EGTs are great, if you're measuring across all cylinders to determine equal combustion across all cylinders however the temperature isn't as important when on E85.

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A single EGT is a great tool for setting the correct timing with E85. Mine sits just after the turbine outlet in the dump.

I agree that individual EGT's is ideal for injector fine tuning, but most people CBF'd with the expense or hassle. If purchasing a new manifold you'd be mad not to have EGT bungs installed though.

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