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DME units
http://forum.44cup.com/viewtopic.php?f=7&t=601		 Page 1 of 4
Author:  joecycles [ Fri Dec 10, 2010 9:56 am ]
Post subject:  DME units
For those of us with early DME units (with the soldered in chips), if you have an unmodified DMe then it poses an issue for the new chip rules (for points, contingencies, etc) as you will need to modify the box to be eligible.

I have looked into this, for me to go to a later DME then I will need to change out my harness and box (and maybe my injectors) or I can buy a BMW spec DME that has a plug in chip that can be spliced and converted to fit my current DME.

Here is my question: If I am running a stock box with stock chip, is there any way to check to confirm that I have a stock DME setup (chipwise) and seal the box without doing a conversion and not spending a lot of money?

Also, do the new chips that are being used for the single mapping better than the stock setup (i.e. do these new chips offer any kind of fuel mapping advantage or HP/TQ advantage or change)?

I ask because I don't want to spend a ton of money and my car is eligible for SP1 and 944spec and I understand that it may kill my ability to be legal in those classes.

Any help/comments are appreciated. I apologize for stirring up the pot but I would like to make sure that it is worth my while to go through the pains if I am racing in 2011.

Thanks

Joey Sullivan
#29 944 cup
Author:  JohnB [ Fri Dec 10, 2010 11:19 am ]
Post subject:  Re: DME units
The BMW board is pretty easy to do and cheap especially if you are capable yourself. Otherwise it's an hour or two labor. And needs to be done reasonably gently. If you do that maybe DD can hook you up with a means to get a copy of (someones) stock chip. Check with him. I think that should be doable.

Yes. That would technically be no legal for Spec. But it would be a stock chip mapping ...

It's not that hard to marry a later Porsche box up to the early motor or vice versa. There's an how to on - another - board. Pretty sure you do not need to switch the harness just splice appropriately.

For whatever reason Porsche boxes are pricey. Again, DD may be able to point you to a source. With two boxes you could switch out to run Cup or Spec.

On the other hand. Now that the boxes are going to be sealed it seems not unreasonable that Behe could certify an early box and just seal it. That would be far more secure than the plug in chip boxes (will be) even with their special chips and seals.
Author:  Director [ Fri Dec 10, 2010 4:34 pm ]
Post subject:  Re: DME units
joecycles wrote:
................Here is my question: If I am running a stock box with stock chip, is there any way to check to confirm that I have a stock DME setup (chipwise) and seal the box without doing a conversion and not spending a lot of money?

Joey Sullivan
#29 944 cup



The stock chips have multiple calibrations, aka maps, which then accomodate munipulation for switching maps to trick the dyno, and therefore the reason the stock chips need to be changed out for a one map chip.

joecycles wrote:
.......................Also, do the new chips that are being used for the single mapping better than the stock setup (i.e. do these new chips offer any kind of fuel mapping advantage or HP/TQ advantage or change)?



The certifed chips will only duplicate the map setting or calibration being used by the owner or the one which the owner desires to be on the one map chip. We are not presecribing or requiring what map setting you use, only that you have one map on the chip, of your choosing.
Author:  Director [ Fri Dec 10, 2010 4:45 pm ]
Post subject:  Re: DME units
joecycles wrote:
I ask because I don't want to spend a ton of money and my car is eligible for SP1 and 944spec and I understand that it may kill my ability to be legal in those classes.

oey Sullivan
#29 944 cup


I do not know what it does to your legality in Spec/SP1. Our concern and efforts are for improving the rules and competition in the Cup series.

Once again, a driver is not required to have the Cup certified chip and sealed dme to race in the 944 Cup. You can run a 944 Spec legal chip in the Cup series, but if you do you just are not going to be a Cup Regionnal Champion or National Champion.

Realistically if you choose to run a car prepared as a SP1/Spec car in the Cup series, you are not going to be a Cup Champion regardless of the chip but rather because of other performance limitations required by the SP1 rules. And SP1 are running Toyos so those cars are not eliligble to win Hoosier regardless of the chip. So those with a SP1 car who want to race Cup races, come on out with us with your 944 SP1 car prepared as is and have some fun.
Author:  Director [ Sat Dec 11, 2010 4:51 pm ]
Post subject:  Re: DME units
joecycles wrote:
.......I have looked into this, for me to go to a later DME then I will need to change out my harness and box (and maybe my injectors) or I can buy a BMW spec DME that has a plug in chip that can be spliced and converted to fit my current DME.

...............is there any way to check to confirm that I have a stock DME setup (chipwise) and seal the box without doing a conversion and not spending a lot of money? ................I ask because I don't want to spend a ton of money.

Any help/comments are appreciated.

Thanks

Joey Sullivan
#29 944 cup


And no one should need to "spend a ton of money" to comply with the one map certified dme protocol. As I have recommended, for drivers who would like to make the effort to improve the series by using our new chip/dme rule, you would be best served to contact John Behe at Behe Performance to discuss the best way for you to comply. John is a great resource and is interested in working with us to improve the series and not having you spend a ton of money doing it. Call John before spending a ton of money.

JB sees no reason why the early 944 dme with the 4 fixed rom's cannot be converted to either limit use to just one ROM or using a socket adapter board that will accept a removable one chip removable eprom to comply with the new Cup rule. Cost to make this happen: $75-$100, maybe less.
===============================
Some Basics:

All Porsche 944 Turbo (951) can be chipped 100%
All Porsche 944 from 1985.5 to 1989 can be chipped 100%
All Porsche 944S & 944S2 can be chipped 100%
Porsche 944 from 1982 to early 1985, <25% can be chipped. Some DMEs built in early 1985 were built with sockets. They too can be chipped.

The DME part numbers are the same from 1982 to the end of production in mid year 1985. In late 1984/1985, BOSCH made changes to the logic board. The original four ROMs (masked programmable) were replaced by a single EPROM (programmable ROM). This was done to make manufacturing easier and not because BOSCH wanted to make it chipable. Neither BOSCH nor Porsche condone the practice of running non factory chips.

The pix below show the late dme logic board (1985)and the early (1964)dme logic board.

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Author:  JohnB [ Sat Dec 11, 2010 9:13 pm ]
Post subject:  Re: DME units
Director wrote:
JB sees no reason why the early 944 dme with the 4 fixed rom's cannot be converted to either limit use to just one ROM or using a socket adapter board that will accept a removable one chip removable eprom to comply with the new Cup rule. Cost to make this happen: $75-$100, maybe less.


Just cut the lines to the external coding plugs inside the box then seal the box.
Author:  GregF [ Mon Dec 13, 2010 6:40 pm ]
Post subject:  Re: DME units
I find the entire thread regarding early ( pre 85.5) DME's to be moot.... They do not have an FQS switch. ( at least the dozen or so I have around here do not) There would be no easy way to switch maps with the early DME without including this device somehow. I have converted dozens of early DME boxes from the 4 chip to single chip using a solder on daughter board. The board is pretty much no longer available and it is not cheap to do. I have had good luck finding older cars that had the ECU changed by the dealer or similar service facility that incorporates the single, replaceable chip.
It does look like the BMW DME conversion will be the "fix" for the older cars in the future, and I don't know if they have a FQS switch or not. Greg F
Author:  Director [ Mon Dec 13, 2010 7:29 pm ]
Post subject:  Re: DME units
More on the FQS:

Early BOSCH Motronic DMEs are equipped with an 8-position Fuel Quality Switch. The switch allows the DME to adapt both fuel mixture and ignition timing for the quality of gasoline available. The Fuel Quality Switch allows the user to correct fuel related engine problems.

See Chart attached here:

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Author:  GregF [ Tue Dec 14, 2010 3:52 pm ]
Post subject:  Re: DME units
The early ( 3 pc ) housings have a plastic plug that is driven into the housing. I finally managed to pry the damn thing out and did indeed find an FQS. My apologies for my earlier post, learn something new every day. ( then old age makes me forget.... Greg F
Author:  Director [ Tue Dec 14, 2010 8:05 pm ]
Post subject:  Re: DME units
ps. the little blue thiny in the pix above, on the left side of the logic board is the actual fqs.
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