Coil Dwell Settings with ProTuner & AccessPort
05-11-2012, 09:02 PM
#126
What is funny to me over all this is the way MM behaved way back at the start (3-4 yrs ago) . All he needed to do was say "I'm not sure how the table works but if you do this ...... it works " . Instead he got as much mileage as possible out of it when he really didn't understand how the table worked himself. Typical of his behaviour throughout his time here .
And MM - if you are reading this by chance.......... I'm laughing at your inability to respond to this .
And MM - if you are reading this by chance.......... I'm laughing at your inability to respond to this .
Last edited by Brettus; 05-11-2012 at 09:06 PM.
05-11-2012, 10:30 PM
#129
and also reading this: http://www.dtec.net.au/Ignition%20Co...alibration.htm
05-12-2012, 08:08 AM
#130
good article---lately i have been watching the systems voltage as controlled by the pcm. There is a certain point in which the pcm will supply over 14 volts to the system. I have been able to identify that this occurs at a certain fuel injector duty cycle, but never related it to the coil. Perhaps there is a correlation? IDK for sure.
I am running the oem dwell map with msd 8247 coils. The coils require a 3ms dwell. They have been performing well--no problem with start up hot or cold, no misfires. But after seeing this information--i do wonder if they need a little bump in the higher rpms.
I am running the oem dwell map with msd 8247 coils. The coils require a 3ms dwell. They have been performing well--no problem with start up hot or cold, no misfires. But after seeing this information--i do wonder if they need a little bump in the higher rpms.
05-12-2012, 03:10 PM
#132
didnt say the increased voltage was for the coils. I just noticed it was there. What is the voltage compensation for the coils then? The table goes up to 15-16 volts. God forbid.
The mercury coils are suppose to not require much dwell and should do great with the oem dwell settings. Making your own harness?
The mercury coils are suppose to not require much dwell and should do great with the oem dwell settings. Making your own harness?
05-12-2012, 09:51 PM
#135
i am not making myself clear? if my voltage to the coil is increased to 14 volts--then my dwell will not need to as long as it does at 13 volts. That is what I am saying.
I dont know that the coils are actually seeing 14 volts. I do know at certain points that much voltage is in the system. I would need to see what voltage is actually being delivered to the coil before i change any dwell settings? Thats my point. Or do you just increase the dwell settings in the cobb table without worrying about what voltage is being delivered? That doesnt make sense to me...
I dont know that the coils are actually seeing 14 volts. I do know at certain points that much voltage is in the system. I would need to see what voltage is actually being delivered to the coil before i change any dwell settings? Thats my point. Or do you just increase the dwell settings in the cobb table without worrying about what voltage is being delivered? That doesnt make sense to me...
05-12-2012, 10:17 PM
#137
weeeeeeeeee
iTrader: (12)
OD,
I believe the table is voltage based so it isn't a matter of adjusting your values based on nominal voltage from your battery.
I think your question is more around whether the ignition circuit needs more reference voltage to deliver the right dwell at higher RPMs.
I've noticed the voltage jump myself, but have never correlated it to anything other than charging the battery. I'm pretty sure I saw it the other night in my driveway while idling.
I believe the table is voltage based so it isn't a matter of adjusting your values based on nominal voltage from your battery.
I think your question is more around whether the ignition circuit needs more reference voltage to deliver the right dwell at higher RPMs.
I've noticed the voltage jump myself, but have never correlated it to anything other than charging the battery. I'm pretty sure I saw it the other night in my driveway while idling.
Last edited by ShellDude; 05-12-2012 at 10:20 PM.
05-12-2012, 11:07 PM
#138
i am not making myself clear? if my voltage to the coil is increased to 14 volts--then my dwell will not need to as long as it does at 13 volts. That is what I am saying.
I dont know that the coils are actually seeing 14 volts. I do know at certain points that much voltage is in the system. I would need to see what voltage is actually being delivered to the coil before i change any dwell settings? Thats my point. Or do you just increase the dwell settings in the cobb table without worrying about what voltage is being delivered? That doesnt make sense to me...
I dont know that the coils are actually seeing 14 volts. I do know at certain points that much voltage is in the system. I would need to see what voltage is actually being delivered to the coil before i change any dwell settings? Thats my point. Or do you just increase the dwell settings in the cobb table without worrying about what voltage is being delivered? That doesnt make sense to me...
The ecu knows what voltage is in the system . The dwell table references voltage and rpm so the ecu looks up how much dwell it needs at that voltage and rpm according to what the lookup table says .
05-12-2012, 11:49 PM
#139
Unless you are continuously exceeding 10,000 rpm or trying to make your D585 coils last a lifetime there is no need to run less than 5.4 mS anywere @ 12 volts or relative equivalency at other voltages
One of the reasons the normal LS2 coil doesn't need as high of dwell settings is because it's output is less than the D585 coil. It is not really recommended for FI applications, though is probably adequate for Na or lower boost settings.
One of the reasons the normal LS2 coil doesn't need as high of dwell settings is because it's output is less than the D585 coil. It is not really recommended for FI applications, though is probably adequate for Na or lower boost settings.
Last edited by TeamRX8; 05-12-2012 at 11:53 PM.
05-13-2012, 09:43 AM
#140
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to get it clear for a noob .. is it safe, to still multiply the dwell table with 1.45 for the BHR coils ?
Especially at the lower rpm range ?
because i have a maß with that setting, but i'm not sure if it will be safe to the engine and coils itself.
thanks for the answer
br,
EdFred
Especially at the lower rpm range ?
because i have a maß with that setting, but i'm not sure if it will be safe to the engine and coils itself.
thanks for the answer
br,
EdFred
05-13-2012, 09:52 AM
#141
i know I am a pita sometimes fellows. I appreciate yall trying to explain things to me.
The oem dwell table didnt make sense to me at all. Oltmans does.
Since my coils needs 3ms-- i need to figure what percentage to adjust the higher rpm cells.
this may be posted somewhere else IDK but for those interested (maybe Brettus?)here is a factory dwell map ( from a SUV) using the d585 coils:http://i305.photobucket.com/albums/n...5CoilDwell.jpg
The oem dwell table didnt make sense to me at all. Oltmans does.
Since my coils needs 3ms-- i need to figure what percentage to adjust the higher rpm cells.
this may be posted somewhere else IDK but for those interested (maybe Brettus?)here is a factory dwell map ( from a SUV) using the d585 coils:http://i305.photobucket.com/albums/n...5CoilDwell.jpg
Last edited by olddragger; 05-13-2012 at 03:27 PM.
05-13-2012, 04:20 PM
#143
In the case of the std LS2 coil, or any coil, you can't just go changing dwell blindly without considering the whole picture. As dwell is increased so is the coil amp draw.
In the case of the std LS2 coil you can see in this link
https://picasaweb.google.com/m/zoom?...portHeight=268
that the coil reaches saturation at 4 mS dwell, but at this setting the current draw on the coil power supply wire is close to 12 Amps. Even at 3 mS it is around 8.5 Amps which is pushing it on the OE wiring harness. If you exceed the current capability of the harness it will melt down and the end result would likely not be good.
.
In the case of the std LS2 coil you can see in this link
https://picasaweb.google.com/m/zoom?...portHeight=268
that the coil reaches saturation at 4 mS dwell, but at this setting the current draw on the coil power supply wire is close to 12 Amps. Even at 3 mS it is around 8.5 Amps which is pushing it on the OE wiring harness. If you exceed the current capability of the harness it will melt down and the end result would likely not be good.
.
