Yeah ok. I'm using 3 degrees (but haven't had time to test) It's a shame we don't have access to the LS, AS and HS governor settings to be able to adjust lope/hunt etc I have a manual, and hate the low speed governor droop settings
Yeah ok. I'm using 3 degrees (but haven't had time to test) It's a shame we don't have access to the LS, AS and HS governor settings to be able to adjust lope/hunt etc I have a manual, and hate the low speed governor droop settings
By the way, I appreciate you doing this calculator, it's going to come in handy!
When you use 250uS where??
Where are you inputting 250uS and getting lope?
there is no inputting 250uS. thats just what the computer has as a minimum.
Im saying i take my RP Map / Duration Map / Pilot maps
Put em all in teh calculator to make sure there is at least a 250uS delay between the pilot end and the main start.
Copy paste it in my rom, reflash and start its not enough pilot timing at all.
I took the output and added 10 just to get the idle pilot timing around where it is stock. and it runs pretty nice. Super quiet, but very un-scientific at that point...
Thanks
Pretty sure the math is
(rpm/60)/1000000x360= deg/uS
3000(rpm)/60= 50/1000000=.00005x360=.018 deg/uS@3000rpm.
So take a 280uS pilot shot at 3000rpm that happens at 52* BMI= 2,888uS between pilot and main at that given moment.
260uSx.018= 4.6* to complete the injection event
Last edited by 2007 5.9; 02-10-2016 at 04:36 PM.
so we can use both. ((3000*6)/1000000)= .018 as well.
Trust me i did the math. your just doing extra math..
Go here if you dont trust me. - Plug in 1 rpm then 3000 - http://www.convertunits.com/from/degree/second/to/RPM
I just didnt want to do all the extra work
Yes it seems I like long form math
You have to keep in mind the ideal pilot timing is going to change based on Inlet Air Temp and Coolant Temp. You will know in a hurry if your settings break that 250us minimum because it will just shut off the pilot wherever you don't have enough pilot timing. I would be curious to know how your minimum pilot timing tune ran after you left the idle range and started driving. On my truck I have found running 5-6 degrees in the accelerating/cruising range to run the smoothest so far with what is basically a constant 160us pulse. This probably differs from most trucks however since my injectors have exergys internal mods and basically flow too much fuel to accurately set up a PW map in the 1-5 mm3 range.
Then you better rework your timing calculator to give you accurate info.
Lets look at stock 2004.5 auto truck cruising down the road at 1550rpm & 30mm3
At those numbers:
Main timing = 7* BTDC
Rail pressure = 15000psi
Pilot timing = 10* BMI
Pilot mm3 = 4
Pilot us = 200
(1550x6)/1000000= .0093*/us
Pilot 10*/.0093= 1075us
1075-200= 875us between the EOP and SMI.
200x.0093= 1.86* of rotation to complete pilot.
10-1.86= 8.14* of rotation BMI occurs.
Show me anywhere in my math or Les's math where the 250us minimum pilot to main time value comes even close to being relevant?
Better yet. Tell me why you would even want the pilot and main events remotely close to being 250us apart?
If your timing calculator is actually plotting your timing values out to be 250us apart, it's no wonder it lopes and runs like crap when you use the values that it outputs
Last edited by Moparmatty; 02-10-2016 at 07:06 PM.
i think i rushed my thought.
I meant if you use the timing calculator to get the corrected Main timing event (as the 50% BTDC equation) it almost overlaps uptop then it eventually does if you rev it high enough.
anyway we are getting off topic. the equations work. I just need to do some more feedback like we have above this response.
But end of the day... I will have to stick it on a dyno to see if what im theorizing is even true...
If others have feedback of how they setup pilot injection please share!
Hopefully my answer above helps answer your question. i wasnt talking about stock maps.
It doesnt make them 250uS apart... this is exactly why i didn't want to post any of the questions up. It calculates the degrees it will need given the RPM and the PW of the Pilot event plus the 250us overlap before the Main event is to start. Its a sanity check to compare against your current pilot map so you dont end up running into the main event. but if Pilot timing isnt based off TDC... then its wrong either way..
Last edited by Bamofo; 02-10-2016 at 07:21 PM. Reason: added more
On the subject of Pilot timing, Les, does 82* pilot timing under heavy load (140+ mm3) seem excessive to you? This is occurring at around 2000+ RPM on up and starts to taper down again around 2800 RPM, although still in the mid 60's. Main timing in this RPM range ranges from 9.5* to 20*, and Pilot pulsewidth ranges from 300 uS to 240 uS in the same RPM range. Seems like there would be quite the long delay between Pulse and Main injection with such aggressive Pilot timing.
The base pilot table is calling for low 50s in that RPM range x commanded mm3, but the ECTxIAT Adder being multiplied by the ECTxIAT Coefficient is resulting in adding another 30*+ of pilot timing, but it is only multiplying heavily when ECT is 180*+ and IATs are 55* or higher (not hard to do). It's adding so much, in fact, that the scanner is logging a limiter named "Clipped" under "Pilot Timing Correction Reason" starting around 2250 RPM and 82.5* pilot timing.
The Pilot Base and Hi/Med HI/Med Lo/Lo density pilot tables have all been adjusted only ever so slightly (removing at most 7* from any one given cell in the 140 mm3 row in that RPM range), but the Adder and Coefficient tables haven't been touched from the stock base.
Just wondering in your experience, if this is common and if it is necessary and/or better to just leave it be. Is there any danger of spraying outside of the bowl with the pilot event, or is there not enough fuel to be concerned about it?
Thanks!
Last edited by B00STJUNKY; 02-10-2016 at 07:17 PM.
I take this to mean that Pilot Timing base table (and all other density tables) are referencing Degrees Before Main Event, then? I was under the assumption that it was a TDC reference, myself, so this could cause even further curiosity and concern about my aforementioned question in regard to seeing 82+ degrees of pilot timing, since that would mean Pilot timing in reference to actual TDC would then be 82 + whatever main timing is (which I presume to be in reference to TDC).
Thanks again for your time and willingness to share.