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How early or late the injection pulse will occur.

But remember as boost rises timing retards.

The autoignition temperature or kindling point of a substance is the lowest temperature at which it will spontaneously ignite in a normal atmosphere without an external source of ignition, such as a flame or spark. This temperature is required to supply the activation energy needed for combustion. The temperature at which a chemical will ignite decreases as the pressure increases (boost pressure) or oxygen concentration increases. It is usually applied to a combustible fuel mixture.

Somewhere around the site in the CR stuff there is a timing map of a stock timing and it got a huge drop in timing.
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you need to be careful with adjusting the timing, as there are alot of guys who have blown head gaskets by running larger tunes on their 6.7l's.You can i believe that if you leave it on 1(which is default), 2 is stock timing, 3 is advanced timing and 4 is super advanced for fuel economy, but not towing.

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On any CR timing is a good thing, to a point. The stock timing (more 5.9 than 6.7, but still) is based solely on emissions. Consider that with my Smarty JR UDC I am running up to 20° more timing than stock in some places, and am not running very aggressive timing!

Since you have a Smarty Jr I would run default timing, you and your truck will like it!

Here is a quick shot of stock timing vs a modified timing. Pink is stock and emissions based, blue is modified and performance/economy based.

Posted Image

Timing is when the fuel is injected into the cylinder, relative to TDC (top dead center). Most timing is before TDC, but I have some ADC at low load/rpms for smoother operation.

Timing is what sets electronic motors apart from mechanical. Even a VE pump, which some timing adjust, doesn't have the adjustability of a CR truck, a VP is in the middle and P7100 is fixed. Adjustable timing is what makes for smoother, flatter, and broader torque curves. Look at P7100 vs a CR truck. With a CR truck you can optimize the timing based on rpm and load, and personally I have a 27° spread from min to max timing.

But you have to be careful, too much timing increases the cylinder pressure, and can cause HG issues and piston melting issues. But generally more timing means more power, better economy, and cooler EGT's, basically getting more power from each drop of fuel. Retard the timing and you get lower cylinder pressure, less power, but better emissions, and HIGH EGT's.

My stock EGT's could pull 1450° towing and not do any damage, as the heat was all in the exhaust not the cylinder. With my modified timing I peak at about 1210° under normal and can touch 1300° if really trying. If I were to hit 1450° with modified timing I could easily melt a piston.

Clear as mud?

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