Smarty UDC Initial Impressions

Well I've been up and down the timing curve and can't pass 18.5 MPG Any suggestions on what to try next? I did cut back on rail pressure to clear up smoke issues. I drive it a hundred miles a day and it's great but want the same or better than the S06 gave me which was 21MPG!
 
Take a look at the s06 files. It might give you a idea on where to make changes.
 
have you logged you tps to see what % you are at while cruising and watched rpm?
 
Yeah I write down tps and load and what rpm it seems to be smoking or rattling and make changes. I cruise at 2000rpm at about 16% load of course hills change load but on average 16 to 20 gives me 18mpg.
 
OK so i dropped rail pressure on the first 5 bars across the board and bam I'm at 20mpg!! Now I have to fine tune and I'll be happy! Still confused about the grand canyon look of the timing chart! tryed to smooth it out with one bump for cruise but it smoked real bad!
 
Instead of bumping the timing for cruise, lower the mid range. Like I said before, I run less timing than stock in the cruise range of 1600-2000. It really should only drop as you go from cruise to accel/spool zone, and instantly start climbing again.. not steep but climbing.

If you look at 2K rpms, it should slowing increase until about 25% load, then back off a little, and then little bit more and at 37.6% I start to increase it again. At 50% load my timing is just barely more than it was at 25% load. At least that is what is working for me, smoke free, insane spool, good accel EGT's, and very smooth driving.
 
AH64ID said:
Instead of bumping the timing for cruise, lower the mid range. Like I said before, I run less timing than stock in the cruise range of 1600-2000. It really should only drop as you go from cruise to accel/spool zone, and instantly start climbing again.. not steep but climbing.

If you look at 2K rpms, it should slowing increase until about 25% load, then back off a little, and then little bit more and at 37.6% I start to increase it again. At 50% load my timing is just barely more than it was at 25% load. At least that is what is working for me, smoke free, insane spool, good accel EGT's, and very smooth driving.
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I'll give it a shot ! The more I play with it the more i understand thanks for the info!
 
The family and I went for a drive today and I was reminded how long it takes the entire truck to warm up. We drove about 100 miles and I bet it took 35 or so before everything was hot. During the first 20 miles I was cruising level at about 4 psi and 750* at 68 on level groung at 35-37* with less than 3 mph of wind. On the return on the same route with the same conditions I was at 2 psi and 600-650 with a few % less load too. The only difference was the temp of then trans and diff fluids, it just takes a long time to warm all that stuff up.

My point is if your doing test runs in winter you need to add extra miles for temps to stabilize so you can see how the truck reacts to the changes. Many people blame the fuel for poor mileage in the winter, but I really think its only a small percentage with the cold fluids being a big one, followed shortly by cold/dense air.
 
Would think a winter program to take advantage of the cold air could make some additional HP?
Sent from my SAMSUNG-SGH-I747 using Tapatalk 2
 
Or some extra mpg once warmed up

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2
 
Cold air does increase horsepower potential, but also decreases efficiency. Warm air is better for mileage than cold air.

You could run a winter tune where you run more duration than a summer tune.
 
AH64ID said:
Cold air does increase horsepower potential, but also decreases efficiency. Warm air is better for mileage than cold air.

You could run a winter tune where you run more duration than a summer tune.
Click to expand...

How is that possible? ALL of the class 8 builders do all they can to jam as much cold air in for both petformance and mileage, why would our trucks be any different?.

Sent While Touring The NorthEast!
 
maybe cold air on a test stand vs cold denser air to drive through pushing our brick shaped trucks though, denser air requires more hp, that isn't quite offset by the boost ya get from burning cold dense air.......... jmho
 
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Well I finally got over 20mpg! I'll attach a sample here. I only wish the smoky haze on medium acceleration would go away! I look like an old semi powering up a hill!

Ok So when I try to download the sample it says invalid file?? Any help?!
 
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I've noticed that all the samples are the same from 0 to about 50% They all look squared off and up and down valleys. Seems everyone is smoothing out the timing graph with a gradual climb in timing. I did this and it just doesn't feel right in the lower rpms
like it's fighting its self. Is there a reason for the way it is? When I look at the 2D graphs I feel I'm not reading them correctly. Each percentage graph goes from 0 to 3500 rpm but only for that section. So in the real world load increases quickly and you would have to look at load versus rpm climbing thru each section....... OK so I may be reading to much into this!
On another note rail pressure has a direct effect on Milage! I dropped rail pressure to
16k in cruise section and lost 2 mpg! Bumping it back up to 18k or should i adjust something else?
 
If you drop rail pressure you will have to adjust timing to compensate for it.

The samples are all stock, or near stock, below 50%. That's where individual trucks all are different based on mods, and where you will spend most of your tuning time.
 
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