Check my work please?

Hey guys, first attempt on a modest tune. Not looking for crazy power just a good running truck with decent MPGs. Little background on the truck..... It is a 2007 megacab with 5.9 I picked it up last November with 157,000 miles. It now has new bosh injectors, airdog, 4in open exhaust, stock airbox (for now), auto trans, 373 rears, 285/70/17 tires. The motor seems healthy (aside from getting used to black oil 50 miles after a change)The truck was bone stock when I got it. It started to smoke occasionally and engine rpm started to hang beginning of this year so tax return went into injectors instead of other goodies. I've had Hptuners for a while but only played with LS engines. I don't have an EGT yet but I monitor other info with the vcm scanner. I don't want to burn the wheels off the truck (yet hahaha) just want a little more power and MPG. Any insight would be great and much appreciated before I drop it in the truck and find out the hard way.....

Thank you in advance!!


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Also just curious if anyone could shed a little light on the 48re. Can we raise pressure and change shift points like a 4l60?? The tables are not making much sense to me. I have been looking for some reading material but am coming up kinda dry... thanks again!!

48RE is not comparable to the 4I60. The 48RE is basically a modified TorqueFlite. The tables HP Tuners shows for the 48RE make perfect sense, they are output shaft speed and throttle position thresholds to allow 3-4 or 4-3 shifts or 3rd lockup/unlock or 4th lockup/unlock with the exception of 4th lockup also being based on boost pressure. Line pressure is what it is, only way to get more line pressure is a modified high pressure pump. 1-2, 2-3, 3-2 and 2-1 shifts can be altered by your gov pressure table and TTVA table, this will also affect shift firmness. You will not be able to change anything far from stock and will not get consistent shifts/lockup/unlock without modification to parameters you don?t have access to.

Thank you Jim, I didn't mean the tables didn't make sense, guess I should've said I didn't quite understand them. I was thinking about installing a shift kit but don't want the super harsh shifts they can sometimes produce. I will continue to look into some more information on the transmission operation.

Shift kits/valve bodies are how majority change transmission shifting and firmness as basically no one knows how to do it through the ECM. Essentially what they do in shift kits/valve bodies is modify passageways and spring tensions to get the results the maker desires, altering the governor pressure vs balancing pressure I think it was, on the other side of the TTVA. Same results can be achieved through the ECM after modification to parameters in the ECM which will in turn free up the adjustability of the gov pressure vs TTVA angle and the shift/lockup/unlock tables.

You wont hurt anything with that tune, but its not going to run like you want. There are a ton of limiters/governors left untouched that wont let the ecm command full fuel. Timing map needs to be copied and pasted into every air density timing table too. Dont be afraid to dig back in time through this forum, lots of great info, logs, and tunes shared and lots of really smart people with great advice.

That's awesome thank you sir. I was leery on copying the timing maps due to people have altitude issues. Being I mostly live at sea level I will paste the timing maps in. I will look into the governor tables to see what I missed. Just a question though.....when I was logging I did see my total fuel rate go up to 140mm3 so what did I miss as far as limiters?? I figured if it commanded 140mm3 (+ -) it should follow the map right?? Sorry I didn't lost up a log. Been working off my phone the past few days as my computer just took a shit.....

Im at sea level and ive always just copied and pasted to every map. Air density gov, high speed gov low limit, smoke limit table, full throttle fueling tables, max output limit, torque limit, Main pulse limiter, is what I noticed. Youll still hit 140mm3 in certain conditions, but if you make some changes it will be a lot more consistent to boost and pedal position. Although, if im wrong there are more knowledgeable people who will correct me haha! Also, did you copy and paste the whole timing table from a timing calculator?

Ok I am seeing all the limit tables now. I will bring them up to the 140mm3. You would never guess there was that many table stopping fuel!!! that is just crazy hahahaha. I did use a calculator to get me close. I was going to fine tune afterwards depending on smoke engine noise and MPG.

I was looking around for tunes to check out just to get an idea of a starting point, but most of them have been locked or removed. The diesel forums are far less user friendly than the gas forums as far as tunes to look at. its all good though I like the challenge!! I am hoping for a smooth powerful economical truck when all said and done. I will say being new to diesels its so easy to fall in love!! I've had this truck little over a year and don't know how I managed with out it!!! hahahahaah

I will have to borrow my daughters computer this weekend to finish it up. I "borrowed" it to load up the software and take a quick look hahahaha

Weird how you cant see or download most tunes, I just checked a few older threads from when I first got into this and I can still load them. As far as your timing goes, some areas the calculator will work good, but a lot of areas it wont be optimized. It really helped me understand when I was able to look at a tune, some areas will have 5-8*, then some areas will have -15* and then on the big end your calculator will do a decent enough job. Just remember, every truck is different, you'll have to make changes and log it, then again, and again lol. This forum has taught me a ton about diesel tuning, lots of great info hiding in threads!

There is a density select table you can use to set the ecm to only follow one table which will perform the same thing as copying everything into each separate density table. This will hold true unless the ecm goes into protect mode (low air density), this table is also used for other things as well. 99% of the time the ecm will only operate in "high air density". There is a massive range of limiters in place, each with its own purpose. An FYI to the smoke limit table, that table is correctly called the Lambda Equivalency table. It sets the max computed Lambda EQ limit for the corresponding cells in the table but is only active between 50mm3 and 200mm3 of commanded total fuel quantity. Lambda EQ is the inverse of Lambda (1/Lambda), Lambda is just another form of air/fuel ratio (Lambda=AFR Actual/Stoich(14.65 for diesel)). Smoke threshold on a well tuned diesel is about 16:1 AFR or about 1.09 Lambda or 0.916 Lambda EQ.

Thank you guys very much! I will continue to dig around and look for information. I've been lurking on and off for a few months just now had some time off of work to play around. I will hopefully be able to make those changes and dump the tune in this weekend then log a few runs.