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Damn my stomach is sick!
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Discussion Starter #1
I know that it have been probably already posted but I'd like to have updated feedbacks about the your EGT readings!
Please post even at how much boost, turbo set up and all!

Thanks!
 
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Carlo,

What AFR are you seeing and what gear and what boost on what gas? too many questions :)

Kaz
 

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Lets go Nets
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dont have one... i guess im due for one...
Brett
 

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800-810, 40-100+ pulls,probe where #6 runner meets collector, SP header (HKS knockoff)
gFForce ECU (no timing mods)
1.6-1.7 kg/cm2 on 99 MON unleaded
AFRs are 11.0-11.2 in 3rd on auto, a little richer in 2nd

What are you seeing Flavio?

Mike
 

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kaz-My afr is between 11.3-11.7:1. This is a 3rd gear pull (auto) at 1bar on 91 octane. I still havent had a chance to turn the boost up and put race gas in because im waiting for my new converter to come in so I can install my SP gen 1 tranny.

carlo
 

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Damn my stomach is sick!
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Discussion Starter #10
Mine are always between 670/700 when I pull strong.
But my probe is immediately after teh turbo.
I guess if mine are too low...
 

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silverstar said:
i´m not very sure but after turbo= ~720-760° and in the collector + 100°.

You have then the most power.
You should be very carefull tuning by temperature. Timing can have a HUGE effect on the temp and power. To say you will get the most power at that temperature is not a safe statement.
 

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AtomicFabio said:
Mine are always between 670/700 when I pull strong.
But my probe is immediately after teh turbo.
I guess if mine are too low...
670-700 doesn't sound low with the probe after the turbo. I don't know how big of a temperature drop happens across the turbo but I'd guess it would be at least 100-150 deg C.

Mike
 

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Mike_Austin said:
800-810, 40-100+ pulls,probe where #6 runner meets collector, SP header (HKS knockoff)
gFForce ECU (no timing mods)
1.6-1.7 kg/cm2 on 99 MON unleaded
AFRs are 11.0-11.2 in 3rd on auto, a little richer in 2nd

What are you seeing Flavio?

Mike
Say if you leaned it out to 11.5:1...would you be very confident that the EGT temps would go up? Are you very confident that the EGT's will pretty much tell you the a/f ratio if NO other changes are made?

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TT_6SPD_95 said:
Say if you leaned it out to 11.5:1...would you be very confident that the EGT temps would go up? Are you very confident that the EGT's will pretty much tell you the a/f ratio if NO other changes are made?

Thanks
Yes but the EGT change with AFR I've heard it's only 30-40 deg C for a full digit change in AFR such as 11:0:1 to 12.0:1. Timing changes can have a much more dramatic effect such as when the ECU pulls timing because it saw knock. I've seen it make a 100+ deg C change in another Supra.

I think EGTs are very useful as an overall indicator but I would never use EGT alone to tune.

BTW, EGTs evidently start to go down again when leaner than 14.7:1 where it peaks.

Mike
 

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Mike_Austin said:
Yes but the EGT change with AFR I've heard it's only 30-40 deg C for a full digit change in AFR such as 11:0:1 to 12.0:1. Timing changes can have a much more dramatic effect such as when the ECU pulls timing because it saw knock. I've seen it make a 100+ deg C change in another Supra.

I think EGTs are very useful as an overall indicator but I would never use EGT alone to tune.

BTW, EGTs evidently start to go down again when leaner than 14.7:1 where it peaks.

Mike
Thanks Mike.

Sounds like there are so many other things going on automatically that you would never really know what to be looking for as far as EGT goes. Everyone just knows to look for the EGT's not going over 850-900C...if it does that you know something is very wrong!!!
 

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TT_6SPD_95 said:
Thanks Mike.

Sounds like there are so many other things going on automatically that you would never really know what to be looking for as far as EGT goes. Everyone just knows to look for the EGT's not going over 850-900C...if it does that you know something is very wrong!!!
900 C in the collector is way too high IMHO. That said, a Supra I know has seen EGTs that high a bunch of times and even 1000+ on a 1/4 mile run where the fuel level got too low and you could hear the lean misfire due to fuel starvation. No apparent damage.

Although EGTs can vary a lot with probe placement, etc, I've got a really good baseline on my EGTs and any change of more than 10-20 deg C is a good indication that something is going on. With peak hold and a warning light on the gauge, it's also a lot easier to spot than trying to read the FJO during a pull. That said, I also datalog my FJO regularly.

Mike
 
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