Confirming D585 truck coil dwell time idle through low RPM improvements
10-05-2010, 07:46 AM
#1
Confirming D585 truck coil dwell time idle through low RPM improvements Searched for truck coil D585 truck coil dwell time info & found that a few had stated improved idle/low RPM behavior. Tried for myself & found that this is the case. Used to rev up to approx. 2100 RPM from idle kind of lazily. Now revs as would be expected up to approx. 2100 RPM & sounds more healthy @ idle. Above 2100 RPM seems the same, but, I kept the higher dwell settings regardless. What was done is that the 5.3L stock GM spark dwell times were copied from a 99 truck from 11 volts 0-8000 RPM through 14 volts 0-8000 RPM (don't remember if it was from an Avalanche, trailblazer or other). After copying the dwell time fields I reduced the dwell time by 2% for safety. Am not suggesting that this is necessary, but figured a little lower is better than too high. Am pleased w/ the results. Again, the dwell time changes were made to D585 coils w/ heat sinks. Could also be done on standard truck coils. Would not suggest making the change to a stock LS1 coil, as I've no experience doing so & it may burn the coil out too soon, if not designed for it. The stock GM LS1 coil dwell time fields are set lower than those of a truck coil in the GM software.
10-05-2010, 08:09 AM
#2
I've had excellent experience running D585's right at the stock truck dwell times. I tuned a 2002 Yukon with D585's, so when I put the same coils on my Camaro, I copied everything directly from the Yukon program in. I haven't bothered messing with the dwell time...hasn't been a need. I guess I don't understand why you needed to reduce the dwell by 2% for safety. GM has these coils running in trucks everywhere at the stock truck program dwell time...been in my car for well over a year and probably 40 or 45K miles...plus however long they were in a truck for.
10-05-2010, 10:33 AM
#3
Hi Mike,
Didn't need to reduce by 2%. Did it because I wasn't sure what would initially happen once the D585 (truck coil) dwell times were loaded, since the D585 coils had been running on stock LS1 coil dwell time settings for some time. After finding that everything was OK, left them @ -2% because I figured that re-adding the 2% in order to match the stock truck settings wouldn't make any difference.
Agreed, the stock truck coil dwell time settings are good & no reduction is required.
Didn't need to reduce by 2%. Did it because I wasn't sure what would initially happen once the D585 (truck coil) dwell times were loaded, since the D585 coils had been running on stock LS1 coil dwell time settings for some time. After finding that everything was OK, left them @ -2% because I figured that re-adding the 2% in order to match the stock truck settings wouldn't make any difference.
Agreed, the stock truck coil dwell time settings are good & no reduction is required.
