Me78569

If it still surges try on lvl 2 only and see if it surges. what base tune are you running? 1000 series, 2000 or 3000?

I would agree the pop delay is what causes the seeminly high timing numbers on the vp44 trucks. Tyler, once you get your truck back on the road with the iquad app I would love to see what load% your truck reports at cruise.

So your truck surges with that custom tuning? What level / levels does it surge on? Generally I would not have the wiretap TPS low set lower than the canbus low. I would change it to this

only if I can ride with you the first time....nothing bad coud happen with the vp44 turned to static 25* timing alright so now that I know what I am looking at in regards to a timing number. At what point does timing start to drop mpg at cruise? Can you have too much other than breaking something? I know every truck will be different depending on configuration, but how do you typically go about building a base map, or is there such a thing.

hahaha, I can see the map now. a bunch of %100 markers from 1200 revs up lolol

I really wish jdonoghue would get back to me. He did a year or so ago, but nothing since.

At least they have some starting point for stuff. Get some rest and let us know if you need anything.

I found in the scipod software where he was calcing out timing /* Timing conversion */ rval = lval; sval = rval >> 7; /* sval is the whole number part */ rval &= 0x7f; rval <<= 1; rval = (rval * 100) / 256; /* The fraction part */ printf("%d.%02d\t",sval,rval); fprintf(OF,"%d.%02d\t",sval,rval); My bitwise math is a little dusty, but it looks like he takes in the timing number "lval" then shifts by 7 to give you the whole number of the timing, then and's the same value to get the remainer and shift by 1. then he does some math to move it into place and prints on the screen. according to this my numbers are still off, 1440 would = 11.25 and 3300 ( my max so far) would be ~24.xx my cruise would be ~ 17.xx IE: Warm idle ~ 11.25* cruise ~ 17.25*-19* WOT ~24* Do those sound better to everyone?

We will likely do an extension cable in our next run as an add on. you could buy a few of these http://www.frozencpu.com/products/3233/psu-184/8-pin_12V_Power_Connector_12-inch_Extender.html?tl=g12c34s276&id=rTniSpzx

Yesir

At normal operating temperature, I'm seeing 11* at idle, and about 16* at 2000 RPM. Light load (little or no throttle) at 2000 RPM the timing is closer to 20*. The map that controls the base timing shows 24* at full load 3500 RPM. Normally, driving around town, I never go past 3000 RPM. I took the base timing table and added 2* to it, and I've been driving around that way for a while. I'm a little afraid of the full load timing at 3500 RPM now - it is 26.4*, which seems awfully high. Of course I can just trim that back down. I left the light-load timing map alone this time - cruising light load around 1800 RPM is showing right around 20* now. Running like this for the past several days, it looks like I've picked up .4 MPG. More info from jdonoghue. My timing numbers now seem to match his about spot on.

Damn someone is feeling saucy tonight..

No because the timing added is on a map in the quad code. as an example, At cruise it would add ~%20 of the user timing, 8 * %20 = 1.6 So cruise timing say 18* from ECM, plus %20 of your 8* advance would give you 19.6* total you only get the 8* you tuned when the timing map is at %100, which is VERY high in the revs and boost. This is where the timing scaling comes into play. If you have it set at %100 then you get that 8* up top, if you set it at %60 then you would get 4.8* up top, BUT lets use the same cruise state so %20 of the map. so you would take your 1.6 * %60 = .96* timing still. the OEM timing from the ecm reached 25* on it's own on the last run I data logged on lvl 0 so we know that the max timing for the vp44 is somewhere between 25* and 30* so using a number like 15 will not give you stupid timing up top, just dumb timing down low.

Alright, I did some math based upon the Quadzilla Code when using 1* of timing increase. This in theory gives you what the canbus message size is for a 1* of advancement. How do these numbers sound. Idle, 13* cruise 17*- 19* Low Boost High load 12* - 14* ( going from cruise state to pedal down) WOT 27* max I have seen. ?

Bigger hammer is all I can say.

We can do that but we first need to be able to be sure how the timing message is formatted. I am Guessing at this point, but what I am seeing seems to be high. How do we figure out what the true timing is? Buy a diesel timing light would be my first though.

Starting point is always the hardest to find haha.

I dunno map the ecm does some pretty nifty stuff.

Well the Quad doesn't calc load in the same manner as the ecm. idle load on the quad = %9 idle load from ECM = %1 according to obdlink program. That doesn't actually mean the obdlink program knows how to decode a load value from the ecm, but something is up. Way I see it we are going to struggle to tune using the quad right now as it doesn't match the ecm. That is why the map is using boost since there is a full range. I might be able to find what the PID is for load via canbus.....maybe.... I wish I had some documents for the protocol.

trying to understand if we can even use load as a tuning variable or not. Does Cummins calc load based upon what is possible via canbus ( 235 + 65 hp) or will it take into account wiretap fuel.

yep just a reflection

mouser pn female side 39-01-2080 male side 39-01-2021 then you will need the pins for them I think

@AH64ID Or anyone else. Do we know how cummins calculates engine load?