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theSLEEPER
Tue, October 20th, 2009, 02:35 PM
How do you stop it other than oil setups? Seems like as small as stock injectors are, that stock oil should be able to keep up. Is it just in the tuning?

cleatus12r
Tue, October 20th, 2009, 02:43 PM
How do you stop it other than oil setups? Less pulse width. The problem isn't the "small" stock injectors, but the amount of time that the injector solenoid is commanded to be on. The fuel chamber in the injector fills to the same amount no matter how long (or short) of time the injector is commanded to be on. The farther the intensifier piston is able to stroke, the more HPO that is used. When you get into really high pulse width, the piston goes a long way.....and when it happens very often (high RPM), then you begin to tax the pump.Seems like as small as stock injectors are, that stock oil should be able to keep up. Is it just in the tuning?

Obviously, the SES light can be disabled for this code. However, it's not recommended because it's masking the problem. There is a lot of performance and efficient fuel usage on the table when the ICP suffers.

theSLEEPER
Tue, October 20th, 2009, 02:47 PM
That's exactly what I thought. I don't want something dumb like a disabled SES, just an actual cure.

Can you still make power at higher RPM's without hanging the injectors open for a long time? Too much pulsewidth at high RPM's is what causes that popping sound right? Or is that a rev limiter?

I wish there were an easy way to convert my splits to singles...

cleatus12r
Tue, October 20th, 2009, 03:05 PM
That's exactly what I thought. I don't want something dumb like a disabled SES, just an actual cure.

Can you still make power at higher RPM's without hanging the injectors open for a long time? Too much pulsewidth at high RPM's is what causes that popping sound right? Or is that a rev limiter?

I wish there were an easy way to convert my splits to singles...

Yeah. There is a way to do it.

More injection pressure commanded at high loads/RPMs.

The injection pressure will kind of work at an inverse (opposite direction) to pulse width up to a point. The point is different for every truck.

If you have 4mS of available pulsewidth at 3100 RPM and your tuning is calling for 2800 PSI of ICP at that point, then realistically you should be able to have the tuning call for 3000 PSI and be able to inject the same amount of fuel in 3.6 or 3.7 mS. This will allow you to run a slightly higher amount of fuel for any speed above 3100 RPM and still keep your pulse width below the threshold...... although a weak pump is a weak pump so if it can't keep up with either scenario then you need a new pump.

The "threshold" is where the PCM and IDM cannot maintain a specific pulse width due to electronic capabilities. The "popping" you mention comes from tuning that calls for too much pulse width and the IDM just gives up and fires an injector when it can. Here are a couple videos for you:

http://www.youtube.com/watch?v=lWU2R1IyouQ


http://www.youtube.com/watch?v=0l7GmU1vvKo

Just ask if you need anything else.

theSLEEPER
Tue, October 20th, 2009, 04:26 PM
That's what I thought. Those videos are AWESOME! Is that you?

cleatus12r
Tue, October 20th, 2009, 09:06 PM
I wish it was me. Nope. I lack the electrical engineering skills required to do anything like that.

I could say it was but that would be a lie.


See the whole thread here:

http://powerstrokenation.com/forums/showthread.php?t=17565