Timing Calculator

**Bamofo** · 02-16-2016

Originally Posted by 2007 5.9

I need to run a few more tests but Im finding that your calc is a couple degrees off when compared to a known calc...

I give more feedabck tomorrow afternoon as I can find more examples than the 2 I ran real quick

keep me posted. if its long you can PM me or email me the answers so i can check why its off. You will see the post above why it could be off by a degree. Once you share feedback ill look and make a V1.1 for you.

**Bamofo** · 03-08-2016

Originally Posted by Bamofo

keep me posted. if its long you can PM me or email me the answers so i can check why its off. You will see the post above why it could be off by a degree. Once you share feedback ill look and make a V1.1 for you.

Anyone with feedback? The calc works awesome for me. Playing with the %btdc to get something as a standard setup to work off of but i was told its off by 1 degree... not a huge deal but would like to know where...

**muz79** · 03-08-2016

I've just downloaded the calc, and I must give thanks to Bamofo for his efforts. Surprisingly my 'educated guess' timing map on my own 2004.5 looks very similar. I base my guesses off sound/smoke/performance/mileage and also tuning other Cummins engine platforms. In my opinion, a single event tune for instance shouldn't sound like a 12v tune. If it's too rattly, it's wrong. You shouldn't need to add a pilot shot in order to listen to the radio at cruise. Granted there will be slightly more rattle than stock, but not like some I've heard.

Rambling aside, I'd like to know what others think about the error in timing in this calc. Keeping everything 50/50 split for this example, my own PW (2606.8uS @ 140mm3 and 160Mpa) and RP (max 160Mpa) tables yield a top timing number of 27.4* (@ 140mm3), although the next number up is 28.3* (@ 135mm3). Is it the dips and hollows in the outputted table that just need smoothing (due to issues with interpolation), or is the whole calc skewed? (I haven't used any other calcs to reference off)

I also have to keep in mind that my tone wheel is spun to give a couple extra degrees static advance, so I allow for this in the tuning. In saying that though, there is some latency between the signal sent to the injector and when it starts to squirt, but I don't think i'll go there...

Muz

**Bamofo** · 03-08-2016

Originally Posted by muz79

I've just downloaded the calc, and I must give thanks to Bamofo for his efforts. Surprisingly my 'educated guess' timing map on my own 2004.5 looks very similar. I base my guesses off sound/smoke/performance/mileage and also tuning other Cummins engine platforms. In my opinion, a single event tune for instance shouldn't sound like a 12v tune. If it's too rattly, it's wrong. You shouldn't need to add a pilot shot in order to listen to the radio at cruise. Granted there will be slightly more rattle than stock, but not like some I've heard.

Rambling aside, I'd like to know what others think about the error in timing in this calc. Keeping everything 50/50 split for this example, my own PW (2606.8uS @ 140mm3 and 160Mpa) and RP (max 160Mpa) tables yield a top timing number of 27.4* (@ 140mm3), although the next number up is 28.3* (@ 135mm3). Is it the dips and hollows in the outputted table that just need smoothing (due to issues with interpolation), or is the whole calc skewed? (I haven't used any other calcs to reference off)

I also have to keep in mind that my tone wheel is spun to give a couple extra degrees static advance, so I allow for this in the tuning. In saying that though, there is some latency between the signal sent to the injector and when it starts to squirt, but I don't think i'll go there...

Muz

If your getting dips and hollows you either have jumps and dips in your PW map or your Rail Pressure Map. I was chasing that earlier and sure enough if its in the RP table... it makes that happen.

Keep me posted as mines running stupid smooth. I have played quite a bit with the % BTDC for cruise and interpolated it to the 50% target at WOT 100mm3+ but yeah overall im super happy with it.

**paulb** · 03-10-2016

First off you've done a very nice job. It shows you understand the problem from a tuning stand point and not just a math one.

One problem I have with almost all timing calculators, is interpolation. I would rather the calculator not try to interpolate. From my experience interpolation works best with a finite data set. In the case of PW, it is infinite within the established range. When an ECM determines what PW it's going to use it uses the surrounding cells as well as the current one (more so the newer the ECM), and it does not use the surrounding cells evenly. Which cells the ECM uses, and how much it uses them, is dynamic, so trying to do a static interpolation is problematic.

Just my .02 worth. Interpolation or not, it works very well.

Paul

**sdimezq8** · 03-12-2016

First off, thanks for contributing to the tuning community!
Can this calculator be used with the 2003 and early 2004 trucks?
Some of the values that are not configurable are different in my early 2004 tables vs what you have in the xls calculator
Thanks!
-Mike

**poulioteri** · 03-13-2016

Works great Bamofo. Same results with another calc but MUCH less time spent. Thanks for taking the time.

**muz79** · 03-13-2016

On jumps and dips in the outputted timing map:
I had already worked through RP and PW to make sure they were smooth. I touched them up a second time just to be sure and still found my timing map a little jagged. 5 clicks on the 'smooth' button soon sorted that out!
Now to wait for the missing pilot timing IAT table to arrive (which is currently being worked on by the HP gods)

**2004 5.9** · 03-15-2016

Either I cant find the value's in hptuners for the timing table, that or switch it from Mpa to psi to match up the tables that way. So I can check how I'm doing with everything

**Tiffo60** · 03-15-2016

Right click the table you have open then select units

**2004 5.9** · 03-15-2016

Is there any way to keep it at psi instead of mpa?

**Bamofo** · 03-16-2016

Originally Posted by 2004 5.9

Is there any way to keep it at psi instead of mpa?

It should stay like that after you save the file.

Same thing with scaling on the X/Y Just make them the same as the calculator and you should be good.

**2004 5.9** · 03-16-2016

I right clicked on the table that is opened next to mpa and changed the units to psi and saved the file, reopened it and it still says mpa

**2004 5.9** · 03-16-2016

04.5 Injector.hpt

If some one could fix it for me that would awesome cause I can't figure it out.

**muz79** · 03-16-2016

I'm sure you'll get it over time. There's all the info you need here, the trick is to work some stuff out for yourself. If you ask people to do everything for you, you learn nothing

**B00STJUNKY** · 03-17-2016

Beyond that, the only way someone could "fix it" for you would be to license the file on their interface. That's gonna cost some coin for a simple "units" selection.

**2004 5.9** · 03-17-2016

Forgot about that

**2004 5.9** · 03-17-2016

Had to go to column or row axis and units then select psi. Just need to sit back and breath for a second and found what i was looking for.

**2004 5.9** · 03-17-2016

on to the calculator. Where do I find the RPM scaling in hp? Been looking for Desired % of Main Event Before TDC for rpm scaling and where to paste the final timing to.

**rcarro001** · 07-13-2016

This worked great on my 04.5. did use the smoothing feature after putting it in. The truck is super smooth & will blow the tires off in second or third gear. I am trying to use this on my 04 but some of the scales are different. If those are changed will it through the whole calculator off? If not what is the password?

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