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Wiggib
July 21st, 2016, 02:31 AM
Ok so I've been dealing with a couple different tuning softwares for about a year now and I'm getting ready to try to tune my 15 Cummins, from what I understand I'm gonna need a .cax file to delete the dpf and other after treatment stuff in the exhaust. I have a template for what looks like ls1 operating systems, with this file could one just convert it to work on a Cummins or do I have to get a different file? Also is there a specific program I need to modify this file? Any advice on this topic would be appreciated thanks.

GMC-2002-Dmax
July 21st, 2016, 02:41 AM
Good luck figuring any if it out. But a tune.

ScarabEpic22
July 21st, 2016, 04:10 AM
To create a .cax to accomplish what you're trying to do, you'll need:
1) JTAG equipment to obtain a straight binary/*.bin file from your ECM -~$10k
2) Hex editor software - free to $1k
3) Intimate knowledge as to how the ECM code functions and where the functions you're trying to map out are -priceless

The LS1 one will not work at all, the ECMs are made by completely different companies with completely different coding strategies. It is a good place to see how the .cax file format works, but the locations/offsets/units/etc aren't applicable to your Cummins.

Hate to say it, but this is why the *big* tuners can charge whatever they'd like for a delete, they've invested the time, money, and hundreds of hours into tracking down the code and building it out.

Snipesy
July 21st, 2016, 06:27 AM
Took me close to half a year as a side project. Of courses it was a different vehicle that had absolutely no support whatsoever.... I know cummins sells their own tuning tool, which is probably silly expensive, but it would probably be easier to make that program do your bidding than trying to reverse engineer the ECM directly.

I'm just talking, never touched cummins, never will.

Wiggib
July 21st, 2016, 07:28 AM
Did you reverse engineer the Ecm to get what you needed? I'm familiar with the Cummins tuning software I actually used to work for Cummins. Anything from a dealership is expensive. I'm really just into finding something that I'm into that can challenge me mentally.

Snipesy
July 21st, 2016, 08:15 AM
It was mostly copycat of EFI Live. I'm not really ashamed to admit it because it isn't as easy as it sounds... Replicate is maybe the more accurate term. The biggest issue is that the vehicles have 'mostly' the same code, and 'mostly' the same paramters. But those parameters have been shuffled around and changed so much that finding similarities between the 2 isn't easy. But at least I could look at the LML, say "Okay I need to find a method like this". I'd then go to the Cruze, find that method, and put the new address in the cax.

EverydayDiesel
July 13th, 2017, 01:03 AM
any hints on this? i write software for a living and hardware on the side.

is there any books or classes on cax files? I want to extend fueling past the factory rpm

joecar
July 13th, 2017, 05:14 AM
Reply from your other thread:



cax syntax can be garnered from reading existing cax files.

As for reverse engineering the ECM tables, you have to do it yourself, or find someone who has done it (they will probably want some payment).