Steve Weiner-Rennsport Systems

Chris W:

This subject is one that I have intimate knowledge of,....

The '96 ECU's (0.261.203.008) contain a special Bosch chipset that are not EPROM's; they are not reprogrammable.

One must have a pair of these proprietary, long-discontinued chips to effect any changes to these ECU's.

Chris W. - '96 Targa

Thanks for the reply, Steve. I was hoping you were following this thread.

Ok, so with the '96 cars you "got what you got", no reprogramming possible to the existing chip. I presume the factory chips are soldered in place, so no plug-in replacement can be done. That would seem to leave three options:

* Use a "piggyback" chip that would clip over the factory chip, disable it, and operate in its place without requiring the factory chip to be physically removed

* De-solder the factory chip and replace with an aftermarket chip that would fill the void in the circuit board the same way

* Replace the ECU with one from a '97 or '98 993 that has a socket for the chip, thereby allowing the plug-in replacement to be made

I've heard of the last option being done (at much more than the ~$850 being quoted by these Powerchip guys -- granted I don't know what Rennsport charges for this). Are either of the first two options viable? If so, are they commonly done?

(As an aside, for me this is more educational than anything. I've not been shopping for a chip, but getting the Powerchip ad from Performance Products sparked the questions, because of the many discussions about trying to chip a '96 car.)

Thanks again Steve for the info...



-Chris

Steve Weiner-Rennsport Systems

Hi Chris;

I have indeed, been following this with interest and some amusement,...

Since these one-year-only ECU's cannot be reprogrammed without having that special Bosch twin-chipset in hand (NLA), the options are:

1) Use the Unichip (piggyback).

2) Install a later (97-98) ECU that CAN be reprogrammed. Those have a single EPROM that is erasable and addressable. Its a plug-n-play proposition if the drive-block is disabled or reprogrammed (by a Dealer).

Needless to say, we do the latter one all the time.

Chris W. - '96 Targa

Steve, again - thanks.

So the remaining million-dollar question is how the Powerchip guys are able to handle the '96 cars (assuming, of course, we all take marketing at face value)... If indeed they have an approach not already covered by Steve Weiner, then I'm sure we'd all like to hear it (Steve included).

Now how's that saying go? "If it sounds too good to be true..."

-Chris

Steve Weiner-Rennsport Systems

Hi Chris:

Unless they have stashed a quantity of those old Bosch chipsets, the only way they might do the 96's would be to install a proprietary module that replaces the original chipset with something of their own.

As always, proper programming is another matter altogether. There is a lot at stake here.

Shant Ohannessian

anyone have a source code of the programming in our 993's? Just curious to see if i can mess around with the code. Myself and a few others deal with programs on a daily bases so i can ask around as well. Thanks

Chris W. - '96 Targa

Source code won't get you much, even if it were available (which I seriously doubt). The "program" itself doesn't need to change; rather, it's the static arrays of values for fuel/spark timing quantities at various RPMs that need to be tweaked. Besides, with a proprietary Bosch chipset, no compilers/assemblers would be available to create the machine code.

Still, as a software guy, I think it would be neat to see the program itself just for kicks...



-Chris

Chuck A.

FYI,

I received this reply from Powerchip as well:

Dear Chuck ,

I am aware of the uniquness of your ECU. Powerchip is the only coimpany in North America that knows how to do this. It is possible to modify the ECU. Is there a telephone number that I can call you on? I would love to discuss this procedure with you.

Kind regards,

Joel Ayson
Mercedes-Benz Power Consultant
Powerchip Inc
233 Wilshire Bvd, 4th Floor
Santa Monica, CA, 90401-1205
Toll Free 1800-495 0777
Ph 310 917 1075
Digital Adrenaline for your engine!
JAyson@powerchipgroup.com
www.powerchipgroup.com

When I have some time, I'll give him a call and find out how it's done.

JasonAndreas

The 993 uses an 8051 variant and the 964 uses that and an M6805 based MCU. There is nothing really special about these chips. Bosch uses the "automotive" grade versions (wider temperature operating range, a few more IO pins, etc.) The 996 probably uses an 8051 object code compatible MCU from Siemens/Infineon (haven't looked yet.) The Bosch Hammer (KTS300) uses a Hitachi 6301 (the same chip was used as a keyboard/mouse controller in the old Atari ST from the late eighties.) If you know what to ask for, the literature departments at Motorola, Infineon, etc. will usually come through with a data book for the chip.

Chris W. - '96 Targa

Cool -- I didn't realize it was 8051-based. I've done 8051 assembly; not too hard. Too bad it's not M6811 based, though. I have the full development kit (development board, EEPROM programmer, UV eraser, etc.) for those from my college days...



-Chris

Shant Ohannessian

Yeah i would like to see it just for kicks and to get an idea for.

96P993

Thought you guys might find this interesting....

Dear Chris,



The ECU on your 993 truely is unique. Powerchip is the only company in the US that has the technology and ability to properly modify your ECU. This means that you can save money on getting your car chipped because you dont have to go out and purchase a late model ECU. I know that, for years, people have been misinformed that the ECU in their simply could not be modified. This is, in effect, false. Most companies eiother do not have the technology, or are simply not capable of doing so. One of the best things about the Powerchip for your 993 is that we socket the chip in the process of modification. This means that you can switch between the Powerchip and your stock chip all on your own after the intial modification is done. If you or any of the board memebrs have any questions. i would be more than happy to answer them, if they give me a call.
Kind regards,

This was sent to me after I sent them a link to this thread explainging the unique position we 96 Porsche owners face...They still are claiming they can chip the 96 ECU.....

Chris W. - '96 Targa

So basically they're saying they take the stock ECU, de-solder the factory chip, solder in its place a chip socket like the '97-'98 models have, and then they are able to plug their chip into it.

Straightforward in concept. Certainly not revolutionary, just tedious (especially if the chip is surface mounted). I wonder how many times they've done it?

-Chris

Rezal

A friend of mine with a '96 just had his ECU reprogrammed by FVD in germany (www.fvd.de). He shipped his ECU out there and they shipped it back a week or two later. I think it was around $500 (but I might be wrong). In addition to adding a claimed 15hp, the reprogramming also got rid of the immobilizer.

I can get more details on this if anyone's interested.