11/14/09 Mid-Atlantic / NE Dyno Day - Roll Call Thread
11-16-2009, 04:39 PM
#143
Well if he got overly happy with the timing I can understand that. What I don't understand is how his car could be strong (from what you guys experienced) one day, and then after he's added all that timing without knock or anything recorded or heard, he puts down such small numbers.
Sounds similar to how my car behaved:
Base timing map. Fully autotuned fuel map. Car pulled very nicely. Installed exhaust. Made sure the fuel was still good. Timing was still base map. Car HAULED MAJOR ***. Then after a run through 1-4th at full throttle, I notice a little smoke coming out the tailpipe. Thought it was me running rich. 10-15 seconds later the tailpipe is CHUGGING out huge puffs of steam. Pull over, and as soon as I stop, steam is coming from underhood like CRAZY.
Was that similar to how neo's car went?
Also notice that melting pistons/ringlands is not common around here. I mean I searched around and there are only a few people that have managed to do this. Then we start using adaptronics and all of a sudden I melt mine, Zxtex melts his supertecs which are forged pistons, and now Neo. Now granted we don't know EXACTLY what's wrong with neo's yet but I'll bet it similar.
So I'm starting to suspect the adaptronic advances ignition more than we think?
Or are we all just timing happy idiots and fucked ourselves on our own?
Sounds similar to how my car behaved:
Base timing map. Fully autotuned fuel map. Car pulled very nicely. Installed exhaust. Made sure the fuel was still good. Timing was still base map. Car HAULED MAJOR ***. Then after a run through 1-4th at full throttle, I notice a little smoke coming out the tailpipe. Thought it was me running rich. 10-15 seconds later the tailpipe is CHUGGING out huge puffs of steam. Pull over, and as soon as I stop, steam is coming from underhood like CRAZY.
Was that similar to how neo's car went?
Also notice that melting pistons/ringlands is not common around here. I mean I searched around and there are only a few people that have managed to do this. Then we start using adaptronics and all of a sudden I melt mine, Zxtex melts his supertecs which are forged pistons, and now Neo. Now granted we don't know EXACTLY what's wrong with neo's yet but I'll bet it similar.
So I'm starting to suspect the adaptronic advances ignition more than we think?
Or are we all just timing happy idiots and fucked ourselves on our own?
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11-16-2009, 04:56 PM
#144
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Sounds similar to how my car behaved:
Base timing map. Fully autotuned fuel map. Car pulled very nicely. Installed exhaust. Made sure the fuel was still good. Timing was still base map. Car HAULED MAJOR ***. Then after a run through 1-4th at full throttle, I notice a little smoke coming out the tailpipe. Thought it was me running rich. 10-15 seconds later the tailpipe is CHUGGING out huge puffs of steam. Pull over, and as soon as I stop, steam is coming from underhood like CRAZY.
Was that similar to how neo's car went?
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11-21-2009, 08:53 AM
#145
I think the problem with most peoples tunes are caused by a difference in dynamic and steady state behavior. Steady state behavior is when the system is ran for long enough that things begin to equalize in temperature and airflow. Dynamic behavior is where things have not equalized yet.
Most dyno sessions only really tune the dynamic region of the car. You make a few changes, do a pull see the results, make a few more changes, do another pull, and see the results. This is great for seeing peak numbers but this is really ragged edge tuning. When your doing it this way the pistons, chambers, and valves are always cool unless your doing some kind of steady state or step dyno tuning. This means the engine can take large amounts of ignition advance without detonating.
In a steady state type of run like you guys were describing things are drastically different. A 1-4th in redline pull is going to take substantially more time then any dyno run. By the time your car is rocketing up to 7k in fourth gear the pistons are searing hot, the valves on the exhaust side are probably glowing red, and the chamber already has steam pockets forming around sections of it causing those areas to superheat. Now taking these two different scenerios and adding the same amount of ignition advance to both will create dramatically different outcomes.
There are ways to safegaurd the parts. Do a dyno tuning session, then add water injection but don't touch your ignition tuning settings. You could also use step dyno tuning and do it like that. You could road tune as well.
For road racers it would probably be smart to create a fuel map that has rich off throttle fuel maps. This would help cool the parts in the turns. Also just flat out conservative tuning is going to prevent issues. Adding an EGT gauge to monitor temperatures is also a very good idea.
I'm not saying the Adaptronic isn't the culprit becuase I have no way to test it at every point and see what its accuracy is, but all of these scenarios kind of happened in the same way after long hard pulls through the gears.
Most dyno sessions only really tune the dynamic region of the car. You make a few changes, do a pull see the results, make a few more changes, do another pull, and see the results. This is great for seeing peak numbers but this is really ragged edge tuning. When your doing it this way the pistons, chambers, and valves are always cool unless your doing some kind of steady state or step dyno tuning. This means the engine can take large amounts of ignition advance without detonating.
In a steady state type of run like you guys were describing things are drastically different. A 1-4th in redline pull is going to take substantially more time then any dyno run. By the time your car is rocketing up to 7k in fourth gear the pistons are searing hot, the valves on the exhaust side are probably glowing red, and the chamber already has steam pockets forming around sections of it causing those areas to superheat. Now taking these two different scenerios and adding the same amount of ignition advance to both will create dramatically different outcomes.
There are ways to safegaurd the parts. Do a dyno tuning session, then add water injection but don't touch your ignition tuning settings. You could also use step dyno tuning and do it like that. You could road tune as well.
For road racers it would probably be smart to create a fuel map that has rich off throttle fuel maps. This would help cool the parts in the turns. Also just flat out conservative tuning is going to prevent issues. Adding an EGT gauge to monitor temperatures is also a very good idea.
I'm not saying the Adaptronic isn't the culprit becuase I have no way to test it at every point and see what its accuracy is, but all of these scenarios kind of happened in the same way after long hard pulls through the gears.
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01-19-2010, 10:02 PM
#155
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I agree, when is the next one of these? I am really sad that i missed out on this one.
There is also a shop near me that has a Mustang Dyno that might be willing to take on a group like this. They are located at Marion, PA 17235. They mostly do ford v8s for drag and circle track, but the owner seemed interested in my miata.
There is also a shop near me that has a Mustang Dyno that might be willing to take on a group like this. They are located at Marion, PA 17235. They mostly do ford v8s for drag and circle track, but the owner seemed interested in my miata.
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01-19-2010, 10:43 PM
#156
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I know of another shop that would be willing to host. York automotive in mt airy md has a dyno dynamics. Owner knows Miatas well among other cars. Anyone interested down this way in a spring/early summer day?
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