Smarty UDC Initial Impressions

Ok I maxed out my timing to 30 and raised timing across the board. I kept timing at 8.5 in the cruise range from 1800 to 2200 load from 0 to 31 and this gave me 21mpg and a max egt of 1300 pulling 20k up a 3 mile steep grade! speed was 70. Load up the hill was around 50% up and down 10% boost was 30psi. Only complaint was heavy haze! Is there anything I can do to reduce smoke? I'm really happy with the tune right now and will post it tonight just wanted some advice. The duration was like sample 30 and rail pressure was around 18000 at cruise and had a gradual climb to a max of 23000.
 
so with your tuning you are able to get over 600 miles on a tank of fuel? I hope you aren't looking at that overhead, set that thing to display outside air temperature and be happy it is close to correct at doing that job.
 
dangerous06 said:
Ok I maxed out my timing to 30 and raised timing across the board. I kept timing at 8.5 in the cruise range from 1800 to 2200 load from 0 to 31 and this gave me 21mpg and a max egt of 1300 pulling 20k up a 3 mile steep grade! speed was 70. Load up the hill was around 50% up and down 10% boost was 30psi. Only complaint was heavy haze! Is there anything I can do to reduce smoke? I'm really happy with the tune right now and will post it tonight just wanted some advice. The duration was like sample 30 and rail pressure was around 18000 at cruise and had a gradual climb to a max of 23000.
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too much timing when you haze.

mikmaze said:
so with your tuning you are able to get over 600 miles on a tank of fuel? I hope you aren't looking at that overhead, set that thing to display outside air temperature and be happy it is close to correct at doing that job.
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And only if your above 20mph... really pisses me off I can't get an accurate temp below 20 mph.
 
I got 300 on a half tank 15 gallons to fill it back up! This is an empty truck driving 65 on cruise! Still have that annoying on off jumping at 2000rpm when going down hill with cruise on!? The overhead said I was at 36mpg! I knew that was wrong but cool to look at! Check the temp only when it's really cold or really hot! and enjoy the climate control!! I reset the scanII and it also says 20 to 22mpg per trip!
 
Your 2000 rpm surge and the tuning to make the overhead say 36mpg are probably from the way you have written your duration map.
 
I dropped my timing .5 across the board to see if haze would go away can't tell right now it's raining and dark BUT my mileage dropped to 17.5 on the scan II damn haze makes a big difference on mileage! I didn't think .5 was that big of a change!
 
In addition to some drivetrain mods I did this weekend I swapped the truck back over to the towing/summer profile from my winter profile. My WAI was plugged and the CAI opened, the winter front removed, the mud tires were swapped for OEM tires, and the PoD went from 70 to 85. The grid heater won't get swapped out for the delete for another month or two, but other wise I am towing ready.

I also did a quick WOT run up thru about 80-85 and WOW. I didn't notice boost, but EGT's pegged at 1125° and there wasn't any smoke, maybe just a light haze which is acceptable. It's also quicker than I remember, I am liking the tune I am running now. I should do some towing on it soon and then I will know for sure how it runs.
 
for my 3k post, AH, I would add some more pressure up top, with that cool an egt, you got room for more fuel, that is , if ya want more power up there.
 
dangerous06 said:
Can you post a sample I am interested in seeing your tune!!
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I have been realizeing that sample tunes from different trucks really don't help other people tune. When you get into tunes like they are one off, and designed for the mods on the motor. Just looking at your mods vs mine I wouldn't expect my tune to work that well on your motor.

mikmaze said:
for my 3k post, AH, I would add some more pressure up top, with that cool an egt, you got room for more fuel, that is , if ya want more power up there.
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I do have some more room for fuel, but I suspect EGT's will go up with sustained use, such as towing, and I will have to see if I have room for fuel then. If I didn't tow I would throw some more fuel at it, but I build my personal tunes for sustained use, not WOT bursts. I have spent miles at 95-100% load at 2000 rpms, or 80-90% load and 2200-2400 rpms, so I have to consider that.

I am not sold on pressure yet, at least for my truck. It does have it's benefits but with my duration I wouldn't gain too much from it. When you are starting to max duration out then pressure can mean a lot more fuel. Just depends on the use of the tune.

While there are places on my pressure map I am 5.6K psi below stock, there are also places I am 4.2K above stock (and they are in places on the map that I use regularly in the summer). So while I don't run pressure over the OEM 23.2K there are places I do use more pressure than stock. You can do a lot with pressure and not get above 23.2K.
 
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AH64ID said:
In addition to some drivetrain mods I did this weekend I swapped the truck back over to the towing/summer profile from my winter profile. My WAI was plugged and the CAI opened, the winter front removed, the mud tires were swapped for OEM tires, and the PoD went from 70 to 85. The grid heater won't get swapped out for the delete for another month or two, but other wise I am towing ready.

I also did a quick WOT run up thru about 80-85 and WOW. I didn't notice boost, but EGT's pegged at 1125° and there wasn't any smoke, maybe just a light haze which is acceptable. It's also quicker than I remember, I am liking the tune I am running now. I should do some towing on it soon and then I will know for sure how it runs.
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John,

What benefits are you seeing when removing the grid heater? I normally remove mine also but, last year I ended up having a PITA boost leak at one of the gaskets, so I'm debating on messing with it.. I know, the boost leak is a minor excuse but was just wondering if your seeing any benefits in removing it..
 
I didn't see too much, but it does seem to help in the mid range with spool, EGT's. Nothing to write home about, but I have the parts and it doesn't take long to swap.
 
Well i bumped up rail pressure and my smoke is gone but my timing is too high rattle at 15-2000 rpm on take off and my mileage is way down. So I guess it's a toss up between milage and smokey haze! I'll go with haze all the time! I love 20 miles per gallon!
 
dangerous06 said:
I dropped my timing .5 across the board to see if haze would go away can't tell right now it's raining and dark BUT my mileage dropped to 17.5 on the scan II damn haze makes a big difference on mileage! I didn't think .5 was that big of a change!
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try adding rail at that cruising point that helps with mileage and also with the haze
 
AH64ID said:
What I have attached is an example of a calculated pulse width table based on stock duration and pressure. To calculate this the ECM (or a timing calculator) will take the desired fuel rate (load) and rpm to the rail pressure table. So lets use 100% load and 2000 rpms. On the stock table that commands 20,885 psi (which is 144 MPa; I use MPa because I only had to extrapolate 156 pressure columns, vs 145x that many). Now if you look at the modified labeling on the duration table you won't find a row that has 20,885psi as a whole number, so we have to extrapolate (just like the ECM will). That extrapolated value comes out to a desired pulse width of 2126us (so it takes 2126us of injector open time to flow 140mm3(100% load) at 144 MPa (20,885 psi)).

So, like I mentioned, the photo is what the desired pulse width will be with stock pressure and duration in relation to rpms and load. This table must be calculated, it's not available anywhere in the ECM that I am aware of, certainly not anything we can see with UDC. The ECM will then blend/calculate between the cells when the load and/or rpms are not exactly as indicated. (i.e. 2050 rpms).

PulseWidth_zpsa57c6404.jpg


Clear as mud??
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I'm pretty sure I understand the math you're doing, but I'm also pretty sure my UDC tables don't give me the data to populate tables relevant to my own engine--would I need a datalogger for that or are you somehow extrapolating everything from your UDC numbers?
 
I am extrapolating everything from UDC, with the corrected labels I have posted in this thread for the duration table.
 
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