Tuning school

rat49f6 · Jun 21, 2012

id like to learn how to read a fueling graph ive seen them and dont get it

2000wa250 · Jun 21, 2012

^^ This....I'd like to not only learn how to read them, but also have a better idea of what goes into all the tuning. As it is I have very little grasp of how things are done. I understand vaguely how ICP and fuel relate, and somewhat about timing, but what other stuff....like pedal %, Temps, all that kind of stuff. Definitely want to get into tuning my own truck, not only because I think it would be nice (like most of us) to be able to make those little tweaks, but also because then I can say that I know exactly what is going on in my engine, and understand how everything works together.

Obviously, before I did this I would definitely want to get into another mode of transportation, and possible have a spare block in case I seriously eff stuff up.

As a bit of a side note (I know there was a split off thread), for those of you who have tuned their own trucks, where did you start? I think this could be the biggest thing for those of us thinking about it because I know right now if you handed me the software and said tune this truck I would have ZERO idea where to even start. I would like to think that after knowing where to start, and having an idea of how things relate, all of us would be able to make little tweaks. I watched Cale make some tweaks to my tuning in spokane, and it seemed to be decently straight forward such as just tweaking the tables (graphs), but where do you start?

JD3020 · Jun 21, 2012

2000wa250 said:
Obviously, before I did this I would definitely want to get into another mode of transportation, and possible have a spare block in case I seriously eff stuff up.

While i was driving the tractor today baling straw, i had lots of time to think, since i was in 1st gear on a loud 60's Deere breathin in diesel smoke creeping through a field. LOL Anyways i was thinking bout this thread and Minotaur, and wondered if somebody has put together a just a basic list of what is considered the "safe" or "normal" ranges for stuff like SOI, ICP, PW, etc.. Just something so that if somebody were to read this thread, purchase Minotaur, and then go out and start messing with different tables that they have a "safe zone" that they can stay within and not have to worry about doing some remodeling under the hood. Or maybe this info is already out there somewhere. :shrug:

Also, little side question/theoretical scenario(that even make sense?). Say i were to buy Minotaur and tune my truck. Then 2 buddies, one with a SD and one with an OBS, both have chips already, want me to tune their trucks as well. Would i just have to buy new definitions for their PCM code and be good to go, or what would it take? I'd call/e-mail Bill or Corey myself but i don't want to take away time from one of their customers because i know how busy they are.

2000wa250 · Jun 21, 2012

From reading their website I would think you could probably get away with just buying the new PCM definitions. However, unless you already had a burner, they would have to have PHP chips. If you already have a burner then I believe it would be as simple as buying the new definitions. If you look on their website it says that if you already have a chip and a burner then all you need to do is purchase the tuning software, and the definitions. If you only have a chip you must purchase the whole package because their chips are coded to only work with their burner.

Another question for those with minotaur. When you purchase it, does it come with not only the stock definitions for your PCM but do you also receive access to standard tunes for standard mods? I'm a bit confused on this part. If it does include standard tunes for your common mods, I'm all in on it because then it simply means that it gives you the ability to make tweaks vs having to write entire programs.

EX: If I was to buy it, would I have to build whole new tunes for my 250/200% single shot injectors, dual hpops, etc. Or would I receive a "base" file so to speak that I could further tweak to account for my engines "differences" vs someone elses engine?

907DAVE · Jun 22, 2012

Hang tight guys, lots of stuff to talk about here. I will not be able to get to everyone tonight, too much to do already.

I will tell you if you already have a chip (probably everyone does) then you need to have a burner that will match. Different vendors use different security bytes in their chips, but no reason you cannot just get a burner to match(if you know what yours is). If you know someone with a burner you can pull this info off of it. If not just call your tuner and have them send you a burner to match their chip.

Secondly, when you purchase Minotaur and a set of definitions you will get a whole slew of files included. These files can be burned strait to your chip to run in your truck, or you can tweak them in any way you please. The great thing about this is you get a real great idea of what and how things need to be changed to get the effect you desire. This will not help those with heavy mods (different injectors, big HPOP's etc). If you fall into the category that will be needing single shot tunes or something tweaked for your "heavy" mod, Bill can put together a file for you to run or build from.

Lastly, there is a ton of support between fellow Minotaur users. There has been many cases where we swap files to get each others opinion on, or help work through a specific issue they might be having. Just remember, you will not be alone!

Dmstrucks02 · Jun 22, 2012

I'll be watching this! Tons of good information here :thumbup:

Powerstrokeracing · Jun 22, 2012

I'm gonna be following this. Great info

OSCS · Jun 22, 2012

2000wa250 said:
From reading their website I would think you could probably get away with just buying the new PCM definitions. However, unless you already had a burner, they would have to have PHP chips. If you already have a burner then I believe it would be as simple as buying the new definitions. If you look on their website it says that if you already have a chip and a burner then all you need to do is purchase the tuning software, and the definitions. If you only have a chip you must purchase the whole package because their chips are coded to only work with their burner.

Another question for those with minotaur. When you purchase it, does it come with not only the stock definitions for your PCM but do you also receive access to standard tunes for standard mods? I'm a bit confused on this part. If it does include standard tunes for your common mods, I'm all in on it because then it simply means that it gives you the ability to make tweaks vs having to write entire programs.

EX: If I was to buy it, would I have to build whole new tunes for my 250/200% single shot injectors, dual hpops, etc. Or would I receive a "base" file so to speak that I could further tweak to account for my engines "differences" vs someone elses engine?

I like your questions, they are keeping this thread where i want it to go

smoker00 · Jun 22, 2012

There's some super good information in this trend... Im in the hevy mod side so I'm going to start to turn my truck..
I Would leave it to the professionals but I'm so far away from anybody to get it live tuned..

It will just work better for my application..

Thank you for the good information .

Gearhead · Jun 22, 2012

The first thing to understand is the engine itself. This may sound like a dumb question but does everyone who is looking to do their own tuning understand how a diesel engine works?

OSCS · Jun 22, 2012

Gearhead said:
The first thing to understand is the engine itself. This may sound like a dumb question but does everyone who is looking to do their own tuning understand how a diesel engine works?

I sure hope so LOL

Shaw · Jun 22, 2012

Gearhead said:
The first thing to understand is the engine itself. This may sound like a dumb question but does everyone who is looking to do their own tuning understand how a HUEI diesel engine works?

missed a word

SDstroker · Jun 22, 2012

injects diesel, makes black smoke to move the turbine wheel and makes boost, right? :lookaround:

Gearhead · Jun 22, 2012

Shaw said:
missed a word

One concept at a time.....lol

907DAVE · Jun 22, 2012

Okay guys, I am going skip way ahead and start with the fun stuff. This is most people are scared of, timing! I am going to throw up a few examples of what not to do. These next few maps will be from a PMT1 split shot file.

**Disclaimer** I do not claim to be a professional tuner so do don't take my words as gospel. If anyone feels I am incorrect or left something out, please say so.

Here's what a stock base start of injection (SOI) map looks like.

The vertical numbers are degree's, bottom left is Mass Fuel Desired (MFD) and bottom right is RPM's. MFD is a calculation the PCM makes that is based off Accelerator Pedal Position (APP) and RPM.

This a stock SOI Delay Map.

This map uses engine oil temp (EOT) on the bottom right and injection control pressure (ICP) rated in Mpa on the bottom left to decide what to do (advance SOI in milli seconds (MS)). This is why its unique, as it is based off time and not crank angle like the base map is. I believe the purpose of this map is to adjust for cold sluggish oil, but many tuners use it as a limiter or adder to keep timing low until EOT reaches normal operating temperature. This map can really get you into trouble if not treated properly.

Now the ugly. Here is a Base SOI map that has been attributed to numerous engine failures. It is overlaying a stock map for effect.

And a SOI delay map that looks like this doesn't help any.

Lets do a quick calculation of the max commanded SOI. First we will look at the max MFD and RPM from the base map. It turns out to be 14 deg. advance, which necessarily is not too bad. Now if you look at the delay map in a similar situation its roughly 1.58 ms.

I have a handy spreadsheet that takes all the work out of figuring crank angles from MS, if anyone would like to have it let me know.

At 3400 RPM (WOT shift) 1.58 ms comes out to 32.2 degrees advance. Stack that base 14 deg. on top and you are at 46 deg. advance.

Yummy.

Discuss.

907DAVE · Jun 22, 2012

Next I will explain how MFD, ICP and PW work together.

05chevy · Jun 22, 2012

I was just looking on PHP site and I seen Minotaur license is $200. Is that $200 per license for each truck? Like EFI Live its $125 per truck.

907DAVE · Jun 22, 2012

$200 for the program. It can be used on as many trucks as you like.

05chevy · Jun 22, 2012

907DAVE said:
$200 for the program. It can be used on as many trucks as you like.

Thats not bad then. EFI Live charges me $125 per license

907DAVE · Jun 22, 2012

The next map is MFD.

This map is what the PCM uses to determine how much fuel needs to be injected, along with a few other things. We will focus on the fueling side of things. Vertical is a number rated in Mg per Stroke, lower left is APP rated in A/D counts (computers way of seeing voltage), and lower right is RPM's.

The next step in determining what to do starts with the ICP map.

This map takes the previously determined MFD (bottom right) and RPM (bottom left) to calculate what ICP (vertical) should be.

From there we go over to the PW map.

Bottom left is ICP (in Mpa), bottom right is MFD, vertical is PW.

Now lets put this all together with an example.

Cruising down the highway with the converter locked in at 2000 RPM's. We'll say the MFD map is asking for 15mg/stroke. Jump over to the ICP map with those numbers and it says ICP should be 1160 psi. Now we can take those two numbers to figure what PW should be. 15mg/stroke at 1160 psi (9.65mpa) will net us about 1.1ms PW.

Now lets roll into the throttle a bit to pass a Honda. RPM's stay the same, but MFD jumps to 53 mg/st. Bring that to the ICP and it wants 2400 psi (16.5mpa). Plug that into your PW map and we get 1.7ms PW.

Neat stuff, eh?