mark kibort

Ok folks, i finally, had a few minutes to take the covers off the original EZK box. the number, kind of hand stamped on the box is EZK 121K
227 400 017 Muster Nr. 28 and with tape, the commonly found, number G18 that i see all over the car on all sorts of things. gear box, fan computer, fan amplifier, etc.

This is the mystery computer, that was run on the car probably at nardo Italy, where it ran 180mph and at bonneville for its slipping, 172mph runs. Ive never run the car with them so it would be curious what they would/could do.

Im a little confused, isnt the EZK box for spark and the bigger gold computer the LHjetronic used for fuel mapping and other things?

anyway, the chip on the box as you can see from the picture has the handwritten numbers on them . Its kind of like an archeological dig. could this chip have the ultimate fuel or spark profile maps???

what do you guys think?

by the way, on that chip is a handwritten date too. its 24th of march 1986, the same month the car went 180mph at nardo.
mk

IcemanG17

Mark
I think your right, the EZK does only the igintion and the LH handles all the fuel mapping...obviously the two need to "talk" to each other a bit. I would send the unit to Rich and electronicrepair...he has the proper tools to determine exactly how its calibrated.....I wonder how the "chips" that the porsche engineers used differ from the autothority or powerchip maps? I would have it checked out before you run it though! There probably is a few extra HP hiding in those computers!

the flyin' scotsman

Mark...........just a quick look at the WSM...........cannot find the number you reference for a EZK unit.
The EZK unit is the ignition brain; the LHS controls the fuel injection.
Word of extreme caution.........the EZK contains many active components (chips) and as such the box and youreslf should be grounded to prevent ESD (Electro Static Discharge) friing your brains!!!

Lorenfb

You never really know about non-standard EPROM chips, i.e. They may be some
factory pre-production devices, ignition maps for a special compression ratio, or etc.
It's also possible that the ECU was switched from another car with a differnet engine
setup when the original EZK failed. So why would anyone risk running an unknown
in their engine, e.g. like a new high revving untested "1/10" weight oil sold only
in unlabeled cans.

Who knows, the standard Bosch/Porsche 10 digit (1267XXXXXX) marked chip may yield more performance yet, as found in most/all LH & EZK ECUs!

sweanders

Talk to someone with a chip reader and have them read the chips, then do a dyno run with them and you should be able to fine tune the data and burn some new optimized chips. If you put those chips in your car not knowing what kind of octane level they are optimized for you might be asking for trouble.

mark kibort

thanks, ill probably send it off to Richard A. to see what he can see and then get to a dyno. it does have the usual EZK numbering , but of course its different than the S4 and the club sport /GT.

It was the box off this car, as it has the G18 all over it too. (not only on the tape left by someone in germany)

I also was careful not to touch any components, and made sure i rubbed my feet on carpet and rubbed a balloon on my head too as i touched it. kidding. its probably ok, and i bet the least i will get is the 6750 or 6800rpm gt type redline. who knows what the spark profile is set for.

Hopefully, rich is willing to check it out.

Rich???

mk

Ed Taylor

Mark, IIRC you said that you did not have the LH box that was the sister to this one? Would be real interesting to see how the maps on both of these boxes differed from stock considering the goal that Porsche had in mind for that car.
Please let us know any voodoo you find.

Rich9928p

Mark,

Sure, I'll check it out. It would be interesting to learn what they did. I have some stock EZKs here to compare it to. As others commented, the EZK is only the spark controller.

Is the Holbert LH fuel injectoin controller a stock unit? If it is, these are the part numbers for an '87 LH box: 928.618.123.10 (Bosch P/N 0 280 002 504). If you peer inside, I'd be interested to know if there is a printed sticker on the EPROM. The stock EPROM number is: 2 287 355 352 or 2 287 355 832. Do not peel off the sticker to look under it, UV light erases EPROMs!!

mark kibort

Rich,
the LH box a stock box purchased from 928intl to get the car running before i bought it. so , unfortunately, its not going to be the sister box to the EZK.
PM me so i can send it to your current address. IM sure we all would be interested to see if the spark map, or programming (or whatever) is different or better!!

thanks,

MK

mark kibort

someone just noticed something interesting. the EZK is a 25pin type, and that is found only on the 86 model year. so, what is the LH box. ill have to check. I assume its a 87 type, as i do have flappy control among other classic 87 type inputs. I did tap into the idle cut off switch, based on the 87 electrical manual, and its definitely working , so illl have to verify whether i have a 87 LH box, as well as the 86 type EZK. If it is 86, does it mean, i dont have knock sensors, found in the ezk? Ive been told that the 86 is 25pin and the 87 is 35pin

what-cha think now??

this holbert car is full of strange things. Im just glad it runs! (and keeps on running, WELL!)

MK

heinrich

Say I need an S4+ EZK ... anyone?

mark kibort

I figure we would hear from Jim at 928intl by now. heck, those guys sold the last owners of the car, the computers to get it running!
MK

John Speake

Mark, why don't you pull the plug of the existing EZK in the car (battery disconnect first) and see if it is 25 way or 35 way ?

mark kibort

I will check it out. by the way, i had my ezk unplug after hitting a birm on the race track. it wasnt secure and the connector pulled away. after a while of checking everything else, found the problem. It may have been the LH box. what happens if you dont disconnect the battery? bad things??? I used to do compression tests by removing the LH plug, so that more fuel wouldnt enter the engine. (guessing). my thinking that .......... wait a minute, i use the same plug that fell off, so im thinking it was EZK, and if you dont have spark, fuel doesnt flow either?.
Ill have to check to remember what box im talking about here , and count the pins on the connectors that are actually being used today.

MK

the flyin' scotsman

Same as rubbing your feet on carpet or your hair with a baloon.........potential boom; pun intended!

The WSM lists all years 1985-1992 32 valve engine ignition control units on pages 28-65 through 28-74; EZF to EZK models. It seems almost every MY had a different ignition control unit with various cut-off speeds. That assumes that the unit has never been opened before with all original proms, eproms and CPU.