Results 1 to 20 of 21
-
09-19-2007 #1
Thermal Imaging for engine tuning and troubleshooting
Hi All, i am working on a theory that thermal imaging can be used as a tool for tuning and troubleshooting 4 stroke engines. I am in the beginning stages of my research but I wanted to try and get the opinions of others that are most likely more knowlegable then me in engine theory.
My goal is to determine if thermal imaging could be a usefull tool especially during dyno tuning of fuel injected engines and I am basing this on exhaust gas temperatures (EGT) in particular.
It is my belief that there are two things that will affect exhaust gat temperatures;- Timing
- A/F ratio
It is also my belief that a lean mixture will cause a higher EGT and conversly a rich mixture will show lower EGT's.
What i am unsure of at this point is what role timing plays in both cylinder temp and EGT so if someone can elaborate on that it would be a good start.
Here is an image I took today of the right bank of my engine at operating temperature. This engine has only seen one dyno tuning session but from what I see it appears that there is a lot of room for improvement to balance all the cylinders. Another question is what would be a good baseline? For example, there is a Delta T ( temp difference) of 206.2* between cyl 4 & 6. Would it be safe to assume that the hottest/leanest a cylinder can run without any detonation is going to derive the most useable power?
In the image above it is quite apparent that there is a huge difference between the hottest and coolest cylinders. All things being equal and timing remaining constant would adjustments to the pulswidth of the cylinder injectors bring the cylinders into a more uniform heat pattern and increase or at least optimize power in the process?
Obviously since this is only an idle test, data would have to be gathered at various rpm and loads. This is where a dyno comes in but I have been unable to get any dyno time donated to do some testing. But I am still working on that.
Sorry about the long post but I am still gathering my thoughts and working out some details on this whole thing.
And in case anyone is wondering about the equipment I am using the IR camera I have is a very high quality ($35k) industrial camera.
-
09-20-2007 #2New to Pro-Touring- Join Date
- Sep 2006
- Posts
- 39
How fast is the response time of that thermal imager? Are we
seeing the instantaneous effect of hot exhaust gases in the
header tubes? Perhaps your photo indicates the heat of the
exhaust gases at one random moment. At another time, perhaps
the other two tubes are hotter.
It's very neat regardless.
09-20-2007 #3Originally Posted by HsvToolFool
My next step is to set the camera up to record video and record the engine heating up from ambient (cold) to stable operating temperature. Once I do that I'll try to post the video and you will get a good idea of how responsive the camera is and also what the heat characteristic of the engine is.
09-22-2007 #4Starting The Transformation- Join Date
- Feb 2007
- Posts
- 327
Ineresting pic. Where I work we have one of those things which you point at something ant it will give you the surface temperature of whatever you point it at. I'm curious about tuning a motor this way too. What kind of engine is this? Is it carbed, throttle body injection or is each cylinder injected? You should have tried to take a picture of the other side about the same time.
Do you have the radiator filled all the way? Maybe there is an air pocket in the front of the motor since they are usually tilted up a little. If your radiator isn't filled all the way maybe that would cause it. I can't remember but I have a book called "how to tune and modify engine management systems" I think it actually does say what a exhaust temperature baseline should be. I'll see if I can find it.
09-22-2007 #5New to Pro-Touring- Join Date
- Sep 2006
- Posts
- 39
Originally Posted by John S
Is it possible that the image captures hot exhaust gases as they exit
certain cyclinders? That might explain the 250-degree difference
between header tubes. In other words, the cool cylinders are on
their intake cycle while the hot ones are on their exhaust cycle.
A video will be extremely neat. That's a cool toy I'd love to have.
09-24-2007 #6