rberry951

Hello everyone,

I'm doing some development work and would like to find someone to do some testing. Specifically right now I need someone with a stock (or close to it) C4 to do some testing. I'll send free parts, you provide feedback on performance. If you have access to a dyno or data logger that is preferred.

Initial testing will be VERY tame, I am not going to risk damaging anyone's automobile. If you are interested please email or PM me.

Regards,
Russell

JasonAndreas

If you are using the free eprom software from Atlantis Consulting (I think the image on your website show it?) with the eprom image from a MY89 C4 don't use it in a MY91+ control unit. Also the displayed units of measurement are all wrong for the 964 (load, ignition timing, etc.) so be careful. You won't damage anything but the numbers don't match reality.

rberry951

Hey Jason!

Well, I paid for my version of Motronic Editor, and hope to work with Marc in developing more features for it. I have a newer C4 stock .bin file that I'm working with right now, I created the .spc file by finding all the maps manually in the code. They keep changing how they do the map descriptor tables so I gave up trying to go by that a long time ago.

I like the Motronic Editor because of the nice visual representation of the maps, it makes it much easier for me to keep track of changes and 'see' them.

Hopefully I'll have a new batch of .spc files to give Marc next week to include with future releases of his software to encompass a few more cars.

I appreciate the input!

Regards,
Russell

JasonAndreas

In the eprom images the map formats are unchanged between models years and even for the 993. The descriptions given on various websites for the formats are wrong and/or missing info. For the 964 all the offsets into the main table are given starting at address 0x. Those offsets (0, 2, 4, 6, 9, 0xB, 0xC, 0xE, 0x11) are relative to the offsets in the main table. For instance the 6 part throttle ignition tables, WOT, fuel, etc start at item 85. The offset tables differ depending on the country and transmission codes.

rberry951

Yeah, some tuners like to move the maps around and try to 'hide' them. I suppose to keep people from trying to modify them and blowing something up and blaming them. I dunno, I just find the maps and make my own spec files, and eat several tylenol. Staring at hex code for hours on end kills my eyes.

Regards,
Russell

JasonAndreas

If you have a MY89-MY90 eprom image load it up into your disassembler and check out the code at address 0x, if you have the MY91+ look at address 0x. I've looked at quite a few aftermarket eproms and some do move the absolute addresses of the maps around but none of them have been smart enough to adjust the relative offsets. If you look at the above mentioned code it will help you understand the reason why.


That's the problem with free software for eprom editing, you end up with the equivalent of script kiddies modifying things with very little idea of the consequences. Or everyone and their brother with an eprom burner selling crap on ebay. Cup chip for the $50USD, no problem I'll just take this beta chip from Autothority and relabel it 964CUP. It won't matter that several revisions later Autothority reduced the ignition timing because of problems their customers were having.

What is really scary is that most of the established aftermarket chip suppliers don't seem to be much better!


It's worth spending the money for IdaPro.

rberry951

I've heard of IdaPro, I think I may even have a eval copy somewhere. I don't bother moving map offsets, standard positions are fine with me.

You bring up an interesting subject, I have found in my dealings with other chip tuners that some are just straight up frauds. And I don't mean coying another mfg code and modifying it and calling it their own. They sell the unmodified mfg code and call it their own. I mentioned that to Marc in passing, he got mad and said he would report someone if he knew them doing that. I'm more of a 'karma' kind of guy. I do things right, and to the best of my abilities, if someone else chooses to be shady, it will byte them in the *** somewhere down the road. You pay for everything, either through hard work along the way, or some other way at some other time. It has come to be a rather strange business. I just got into it market wise. But yeah, anybody can buy a eighty dollar burner and sell other people's chips calling them their own, or maybe even worse yet, tweak them in ways they don't understand and blow up somebody's engine. I would rather error on the side of caution when dealing with someone else's vehicle, and give them a little more driveability, a little less performance than the max I can twist out of it, and save them a huge repair bill.

Thanks again.

Regards,
Russell