Smoke Control

[907DAVE]

Is it just a function of the MFD map?

Or is it the Low Boost Fueling map, PW, etc.?

What is the most efficient way to reduce smoke?

[cleatus12r]

Originally Posted by 907dave

Is it just a function of the MFD map?

Or is it the Low Boost Fueling map, PW, etc.?

What is the most efficient way to reduce smoke? Leave it stock.

Poor (or less than highly efficient) combustion efficiency and the amount of fuel per amount of air are big contributors.

If your program is designed to give you a certain PW at a certain RPM/APP/ICP (obviously there is no map for this, but it all comes out in the wash ) then one fix is to command less PW (multiplier) at that certain RPM/APP/ICP.

Increasing ICP will result in less commanded PW (unless the PW map has been changed...not the PW multiplier map) because the PCM will account for a mass fuel desired difference with the higher ICP and automatically lower the PW.

The low boost fuel maps are a MFD limit. They limit the actual MFD desired to whatever the value is for a given MAP vs. RPM. If you were to lower the low boost fuel to say, "30" across the board, you'd get a total MFD of 30 and have a gutless pig.

Setting the LBF map to an acceptable range while driving like a normal person (it would take some trial and error) and only allowing higher MFD under really high boost conditions would help.

[907DAVE]

<---- thats a good one, thats what I am like everytime I think about this stuff.


If you use the PW Multiplier, it appears you can only reduce PW about 1ms at operating temps. Is that enough?

Or is that value not MS?

More like PW X 1.5 or whatever?

[cleatus12r]

It's a multiplier.

It "basically" takes the desired PW for a given ICP/MFD (in the pulse width map) and multiplies it by the value in the multiplier.

So by all rights, you can either jack up the values in the straight pulse width map to reflect what you want the PW to be for a given MFD/ICP that is not based on EOT so you can really churn out the powah upon first startup on a -10F day........

OR

You can calculate (within fairly close reason) what the actual PW will be if you do some math. The PW multiplier map allows injection pulse width changes based on EOT instead of just allowing a ton of fuel while the engine is cold.

[907DAVE]

So to simplify things a guy could change the PW map to get desired results on a warm engine, then do a little math and apply those changes to the multiplier map? Or would it be just as easy to do this with the multiplier?

[cleatus12r]

You know, for aftermarket injectors that flow significantly different from stock (especially those with larger nozzles) that's probably the direction I would take. Either that or just leave the multiplier map alone and just drive normal until the engine is warm. The base PW map should be changed anyway for large injectors just to get the idle right.