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How are you all handling fueling on boosted, manual cars? The other day I was logging my 2015 5.7 RT and noticed there was quite a bit of timing being pulled but not at WOT but instead at PT. Basically car was in 3rd gear (~2000rpm) and pedal was gradually being applied but enough to where low levels of boost (1-3PSI) was being developed (engine was not quite lugging but in low RPM). Or is it more of a...you need to learn to drive around it...condition?
Knock sensors may need an adjustment or there is an event you need to repair. Either not enough fuel or too much timing. I have my PE fueling start when the pedal is at 1.7vs as that's about where I see boost come in. Then I take my highest KPA section in my VE tables (200kpa for me), copy it, past it to the 100kpa section and enter .85 then hit the x sign, then I highlight everything from 100 KPA down and hit blend vertically.
It would be nice if the spark tables referenced boost instead of aircharge.
If it were my car, I would log the retard in a histogram set up to duplicate the PT spark table and then paste it over to take out timing where you're seeing retard.
It also might be worth looking at the PT vs WOT values where you are having the retard.
errr.. the fact that the table references aircharge is *awesome*. It doesn't have to deal with the crude/incorrect method of "pulling timing in boost".
read the aircharge from the logs, adjust the timing like you would anywhere else in the map. A N/A Car just doesn't have those parts of the spark table mapped out appropriately, as they weren't intended to ever be in that area. once you get that in place everything will be gravy.
Guess I'm just old-school minded with the boost/timing mapping. Easier for me to think of it that way.
I do notice that there are 2 *PE* fuel maps in these cars - one aircharge and one pratio.
I also follow what you're saying, but I'm still trying to figure out what all goes into the "aircharge" calculation. It appears to be mass flow, but calculated instead of measured. Maybe lack of understanding the variables that go into making up aircharge is why I'm cautious.
Homer,
What aircharge are you logging when this happens? Should be easy enough to see if that area of the map has been edited from your stock tune.
By any chance did you change the values for air charge to reflect the same values as a Hellcat? This may be able to clear up some of the issues as stated above the NA cars were never calabrated to opporate in boosted ranges.
My PE aircharge is modified to account for boost but boost seems to be coming on at low aircharge (~0.58g) and pedal voltage (~0.9V...WOT PE is set to 2.0V). So how do get fueling to kick in when boost kicks in at such low pedal/aircharge values? What happens is I slow down to take a turn but I am not slow enough to shift to 2nd so the car is in 3rd so when I power out of the turn, boost develops but there is no fuel to compensate for it. Funny thing is, I haven't really changed the tune since last year except for turning sensed MAP to enabled.
Before I go any further, I need to get my wideband up and running again as it crapped out on me (heater element blown) and re-log. Also, want to get my fuel pressure sensor in the log as well...for some reason it must have removed it from the channels.
Attachment 90708
I don?t think the 5.7 or 6.4 has a fuel pressure sensor. 6.2 does though.
Did you try enabling the pratio fuel table?
That should let you fuel by manifold pressure if it actually enables.
No they do not but I am running an aftermarket fuel pressure sensor.Quote:
Originally Posted by spoolboy
https://www.summitracing.com/parts/i...iABEgKD_vD_BwE
I thought the PE tables only work when the WOT pedal voltage is achieved, otherwise NN is controlling fueling and trying to maintain stoich value? Like I said, my current setting is 2.0V but I see boost when the pedal voltage is ~0.9V. On an automatic car the trans would be shifting to a lower gear but on a manual you could get in a situation where the motor lugs...which is why I was wondering if this is one of those "you drive around it" scenarios as nothing can be done in the tune?Quote:
Originally Posted by spoolboy
BTW I run Shell 93 exclusively and I am pretty sure the knock is real as every once in a while when I am pulling out of a turn I can hear the engine ping. My tip-in throttle spark is not zero'ed out and only halved from the stock values. If I increase enrichment rate much higher than stock (0.0100), like I see in other boosted tunes, my fueling goes pig rich and it throws injector open/short DTCs. I also have drilled out the bypass valve restrictor but I really want it gone just haven't invested the time in smoothing out the low end throttle response when it is removed.