Coal Rolling = Posing
Join Date: Nov 2007
Location: Cumberland Furnace, TN
Thanked 1 Time in 1 Post
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
Feedback Score: 0 reviews
Engine Oil Temp is one of the variables that the PCM looks at to determine timing.
These aren't mechanically timed engines, timing fluctuates slightly depending on like 5 different tables.
But, in relation to EOT, the colder the oil, the more timing the PCM adds. Because the cold oil moves slow.
So, in order to to maintain Start of Ignition (call it SOIg) at an appropriate time, the Start of Injection (call it SOI) timing has to increase. Add a chip that is increasing timing to the equation and you're out of the "safe" zone.
So, let your oil get up to temp. Don't worry about it running at 200*. Some gassers run 250* remember. That's a bit to high for our oil operated injectors, just a comparison.
If you install an oil cooler, the truck may never crest the 180* mark where the EOT values level out and the truck runs approximately 26* of timing, at 3000 RPM's, with 3000 ICP, etc...
The further below 180* you get, the more SOI is increased to maintain SOIg. It makes a much bigger jump below 160*. Like, I try when ever possible to let my truck run at idle until it reaches 160*, then drive it easy until it crests 180* EOT.