how to tune spark at low-load and EGT tuning
#1
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I searched and searched, don't bitch unless you can find the link.
I just got my car back from tuning, and well, I'm a bitch and a little nervous about the turbo and manifold glowing all the time. After I run the car moderately hard, the turbo and manifold will glow for at least 15-minutes (I got tired of waiting in the cold to go further) at idle. There is a ton of exhaust pressure through the pipe at idle, and I can advance spark quite a bit with the car still idling fine and the exhaust turbulence noise and pressure drop significantly.
So what should I do aside from installing the Greddy EGT I have in the trunk make sure everything is safe?
Is there a general how-to on spark tuning at cruise without EGT? Once I install the EGT, what are my target temps, or do I just look for the EGT drop-off? I really want to log EGT and compare it to spark-angle in megatune...that would be cool.
Thanks
I just got my car back from tuning, and well, I'm a bitch and a little nervous about the turbo and manifold glowing all the time. After I run the car moderately hard, the turbo and manifold will glow for at least 15-minutes (I got tired of waiting in the cold to go further) at idle. There is a ton of exhaust pressure through the pipe at idle, and I can advance spark quite a bit with the car still idling fine and the exhaust turbulence noise and pressure drop significantly.
So what should I do aside from installing the Greddy EGT I have in the trunk make sure everything is safe?
Is there a general how-to on spark tuning at cruise without EGT? Once I install the EGT, what are my target temps, or do I just look for the EGT drop-off? I really want to log EGT and compare it to spark-angle in megatune...that would be cool.
Thanks
#3
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I'm about to drive the car from Austin to Houston, to Dallas, then back to Austin, so I'm going to fix this today.
#4
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I drove the car hard for a while, drove about 3-miles back to the hotel, popped the hood and the turbo was beat red for another 15-minutes until I just turned it off. It was dark out too, so take that into consideration before you scare me. Will the ceramic coating hold heat in, that long or cause more glowing. Regardless of the inference, I know the right answer is to hook-up the EGT.
1) Take it easy on the car until you...
2) Install the EGT
Turbos do tend to glow after hard use, but it'd be good to have hard EGT data so you can know that everything is ok.
If temps are within reason but you find you want to end the glowing, send the manifold and hot side off to jet hot for some jet hot 2000 coating action. It's probably way cheaper than you think and, especially if you also do the downpipe, the difference in underhood temps will be incredible.
#6
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I suggest:
1) Take it easy on the car until you...
2) Install the EGT
Turbos do tend to glow after hard use, but it'd be good to have hard EGT data so you can know that everything is ok.
If temps are within reason but you find you want to end the glowing, send the manifold and hot side off to jet hot for some jet hot 2000 coating action. It's probably way cheaper than you think and, especially if you also do the downpipe, the difference in underhood temps will be incredible.
1) Take it easy on the car until you...
2) Install the EGT
Turbos do tend to glow after hard use, but it'd be good to have hard EGT data so you can know that everything is ok.
If temps are within reason but you find you want to end the glowing, send the manifold and hot side off to jet hot for some jet hot 2000 coating action. It's probably way cheaper than you think and, especially if you also do the downpipe, the difference in underhood temps will be incredible.
![](http://i36.tinypic.com/aebebn.jpg)
The heat shielding over the turbine housing was hot but didn't burn my fingers....I wonder if that has anything to do with the glowing. I doubt begi would give it back to me with potential drama like this, but I want to be certain so I can sleep tonight...with lots of women at the same time.
#7
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because I just cut a check (very reasonable price though) for someone to tune this **** so I wouldn't have to because I'm too busy. I don't remember the cruise values, so I'll have to check those later today.
#11
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edit: my gauge is whacked out and reading incorrectly:
![](http://i39.tinypic.com/976zqq.jpg)
perfect AFR from Tim at BEGi (the enchanter?)
![](http://i41.tinypic.com/2hd1c3a.png)
why would they put afr's at 10.0:1?
and here is the spark table after I switched the idle cells from 13 to 17, and there is now much less exhaust pressure:
![](http://i39.tinypic.com/976zqq.jpg)
perfect AFR from Tim at BEGi (the enchanter?)
![](http://i41.tinypic.com/2hd1c3a.png)
why would they put afr's at 10.0:1?
and here is the spark table after I switched the idle cells from 13 to 17, and there is now much less exhaust pressure:
![](http://i39.tinypic.com/2h848hs.jpg)
Last edited by hustler; 01-16-2009 at 04:32 PM.
#13
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I don't know what to do about the MAP signal, I'm already T'd off the FPR vac hose, maybe I need the filter.
Please be more specific on the spark map.
#14
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About the glowing manifold, it doesn't take much to make cast iron glow. Here's a chart:
Metal Temperature by Color
Metal Temperature by Color
#15
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About the glowing manifold, it doesn't take much to make cast iron glow. Here's a chart:
Metal Temperature by Color
Metal Temperature by Color
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edit: When was the last time you calibrated the LC-1?
Last edited by Savington; 01-17-2009 at 01:21 AM.
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For you EGTs Hustler:
https://www.miataturbo.net/forum/t29678/#post345982
Able to log in megatune, i would sell your gauge and do what savington and i plan to do. You will probably end up with extra money after the sale of the gauge as well.
https://www.miataturbo.net/forum/t29678/#post345982
Able to log in megatune, i would sell your gauge and do what savington and i plan to do. You will probably end up with extra money after the sale of the gauge as well.
#20
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It did really well on the way to Houston last night. It walked a new mustang gt from 80mph to 130mph by a hair, and it pulled a 350z 4-times in 5th gear...the guy asked if it was an automtic, lol.
Now I'm done driving like a child and will get this car ready for track pillaging. When do you think the cops will ship?