Holbert Mystery EZK box picture (numbers)
#17
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"Do not peel off the sticker to look under it, UV light erases EPROMs!!"
The "window" sticker can be removed without affecting the memory data
of an EPROM in normal ambient light. Erasure of the data only occurs with
high intensity UV light or very intense sunlight.
The "window" sticker can be removed without affecting the memory data
of an EPROM in normal ambient light. Erasure of the data only occurs with
high intensity UV light or very intense sunlight.
Last edited by Lorenfb; 03-08-2005 at 12:39 AM.
#18
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Mark,
A battery disconnect is "good practise - especially knowing how vunerable a standard LH ECU is.
If you disconnect the EZK, then the fuel pump will not energise, nor will the injectors open at all. This is because the EZK provides the rpm pulses that trigger the LH.
Laren is quite correct about EPROM erasure.
A battery disconnect is "good practise - especially knowing how vunerable a standard LH ECU is.
If you disconnect the EZK, then the fuel pump will not energise, nor will the injectors open at all. This is because the EZK provides the rpm pulses that trigger the LH.
Laren is quite correct about EPROM erasure.
#19
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It has the potential for making a rather sizeable difference ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
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Originally Posted by 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.
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.
#20
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Loren, John, You are right that briefly opening the EPROM window is unlikely to damage it. However, it will erase over time if your ambient is flourescent! BTDT, used to be in electronics manufacturing. A few weeks with the EPROM window open under flourescent lights and we had a 50%+ failure rate. In our case it was a trivial matter to re-burn them, but IMHO this rare chip deserves special care.
#24
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I just checked the computers. Now i know why i was confused. the box on the left, with the connector in the back, IS the EZK, and it is the EZK 227 400 035. (i thought the LH box was the EZK due to its black color) Meaning its the 35pin connector type (although i didnt actually see it as its in the rear, but its got 928intl written on it so, its the stock stuff). This box is gold, while the mystery EZK was black and the 25pin type.
Now, the black box on the right, has the pins facing out and the terminal hinges at the bottom. THIS is the LH jetronic box. No numbers on it, but i does have 35 pins. so, no match to the mystery box. Now, here is where it gets confusing. all the cables are all new from 928 intl., so if that old box (25pin EZk) was used, could the previous owners rewired with stock cables?
Remeber, i do have a working flappy. (but thats controlled by the LH, right)
However, i have no idea if i have knock sensors, or that cam sensor on the passenger side cam sprocket discussed earlier.
Now, the other thing was when i hit that birm in the race, and the car died, it was the LH box that got disconnected, probably the reason there was no damage, as someone pointed out that the EZK if disconnected "live" could be a problem. this is also the reason, i was getting spark, but no fuel through the injectors.
Is there a reason, you dont want to do a compression test while the LH is disconnected? seems like a good way to not send fuel into the cylinders during such a test. what about spark, since one plug is disconnected, should you worry about an open circuit there?
so, since the wiring looms were changed, i have no idea what was there before, and how much of the new EZK they are using. maybe 928 intl remembers, as im sure this conversion would have sparked discussion with JIM!
Mk
still digging, now through some old paper work given to me with the car.
Now, the black box on the right, has the pins facing out and the terminal hinges at the bottom. THIS is the LH jetronic box. No numbers on it, but i does have 35 pins. so, no match to the mystery box. Now, here is where it gets confusing. all the cables are all new from 928 intl., so if that old box (25pin EZk) was used, could the previous owners rewired with stock cables?
Remeber, i do have a working flappy. (but thats controlled by the LH, right)
However, i have no idea if i have knock sensors, or that cam sensor on the passenger side cam sprocket discussed earlier.
Now, the other thing was when i hit that birm in the race, and the car died, it was the LH box that got disconnected, probably the reason there was no damage, as someone pointed out that the EZK if disconnected "live" could be a problem. this is also the reason, i was getting spark, but no fuel through the injectors.
Is there a reason, you dont want to do a compression test while the LH is disconnected? seems like a good way to not send fuel into the cylinders during such a test. what about spark, since one plug is disconnected, should you worry about an open circuit there?
so, since the wiring looms were changed, i have no idea what was there before, and how much of the new EZK they are using. maybe 928 intl remembers, as im sure this conversion would have sparked discussion with JIM!
Mk
still digging, now through some old paper work given to me with the car.
Originally Posted by 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
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
#25
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""Is there a reason, you dont want to do a compression test while the LH is disconnected? seems like a good way to not send fuel into the cylinders during such a test. what about spark, since one plug is disconnected, should you worry about an open circuit there?""
For a compression test, I would reccommend pulling the LH, EZK and fuel pump relays - that should stop spark and fuel.
It sounds as though the EZK is mounted back to front ? Both 35way connectors should be facing you.
The 25pin spark box seems an unlikely partner for your car. It is hard to belive that a LH2.2 EZK was ever used on that car.
For a compression test, I would reccommend pulling the LH, EZK and fuel pump relays - that should stop spark and fuel.
It sounds as though the EZK is mounted back to front ? Both 35way connectors should be facing you.
The 25pin spark box seems an unlikely partner for your car. It is hard to belive that a LH2.2 EZK was ever used on that car.
#26
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sure looks like the EZK is mounted correctly, as its on a plate and there is a coding plug on it as well that we hooked up according to the manual.
for compression tests, i would think that the LH being pulled (i guess after battery shut off) is probably enough, unless that stray spark is a problem as i did remember that spark was still present, even thought LH was disconnected.
fuel pump relay shouldnt be an issue, aslong as the injectors are not firing. there is plenty of fuel in the rails, that if the injectors are firing, it will still dump fuel in the cylinders. I think ive actually had the fuel pump relay pulled and the injectors run and engine runs until the rails run out of fuel
Anyway, im also having a tough time understanding why the old 25pin box is even around. however, why did 928 intl have to provide a harness and two boxes (assumed 2 boxes, may only be the EZK box). was it rewired by crack 928 specialists, or was it just a simple replacement by a couple of 911 guys at the shop that new how to plug in a connector to a box? wonder if we will ever know. Is there anyway to see if im running the knock sensors?
mk
for compression tests, i would think that the LH being pulled (i guess after battery shut off) is probably enough, unless that stray spark is a problem as i did remember that spark was still present, even thought LH was disconnected.
fuel pump relay shouldnt be an issue, aslong as the injectors are not firing. there is plenty of fuel in the rails, that if the injectors are firing, it will still dump fuel in the cylinders. I think ive actually had the fuel pump relay pulled and the injectors run and engine runs until the rails run out of fuel
Anyway, im also having a tough time understanding why the old 25pin box is even around. however, why did 928 intl have to provide a harness and two boxes (assumed 2 boxes, may only be the EZK box). was it rewired by crack 928 specialists, or was it just a simple replacement by a couple of 911 guys at the shop that new how to plug in a connector to a box? wonder if we will ever know. Is there anyway to see if im running the knock sensors?
mk
Originally Posted by John Speake
For a compression test, I would reccommend pulling the LH, EZK and fuel pump relays - that should stop spark and fuel.
It sounds as though the EZK is mounted back to front ? Both 35way connectors should be facing you.
The 25pin spark box seems an unlikely partner for your car. It is hard to belive that a LH2.2 EZK was ever used on that car.
It sounds as though the EZK is mounted back to front ? Both 35way connectors should be facing you.
The 25pin spark box seems an unlikely partner for your car. It is hard to belive that a LH2.2 EZK was ever used on that car.
#27
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Kibort has what is probably the only hand built 928 on the road a preproduction prototype assembled many months BEFORE the assembly line was converted to S-4 and as such had many unique adaptations. It was also purpose built to establish land speed records and the original computers had the chips mounted on the outside so they could be quickly changed. The camshafts are "odd" chances are the engine was "blueprinted " and the intake manifold and ports messaged ,the big question is what if any modifications were done to the crankshaft/oiling which have allowed that engine to run so hard and NOT have #2 and #6 rod bearing fail with no accusump ??
#28
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I hope all that is true! i wonder about the chip replacement theory, but it may be one of the reasons the EZK is mounted in reverse direction. that way, unscrew those 4 philips heads and the board can slide out to the driver compartement for a chip change. (if that was the EZK, but its weird that its the 25pin type. the dates on the chips coorespond to the time it was run in the record breaking runs, especially 180mph at nardo Italy in march of 1986)
i also wonder about the intake, although when Tom and i did some dynoing, the runners looked grinded down. dont know if that was post machining, as it is aluminum, not the coated usual stock version found on prod. S4s.
who knows about the crank. all i can tell you is that when i pull apart my filter, i see no shinney stuff. but, i also use amzoil. ha ha. My old stock 4.7 racer engine also had no wear patterns on #2-6 bearings
camshafts are odd, but probably just a 85 derivative. (ie same as GT)
pretty cool owning something so unique, just hope it keeps on cranking!!! (knocking on wood, hard!!!)
MK
i also wonder about the intake, although when Tom and i did some dynoing, the runners looked grinded down. dont know if that was post machining, as it is aluminum, not the coated usual stock version found on prod. S4s.
who knows about the crank. all i can tell you is that when i pull apart my filter, i see no shinney stuff. but, i also use amzoil. ha ha. My old stock 4.7 racer engine also had no wear patterns on #2-6 bearings
camshafts are odd, but probably just a 85 derivative. (ie same as GT)
pretty cool owning something so unique, just hope it keeps on cranking!!! (knocking on wood, hard!!!)
MK
Originally Posted by Jim bailey - 928 International
Kibort has what is probably the only hand built 928 on the road a preproduction prototype assembled many months BEFORE the assembly line was converted to S-4 and as such had many unique adaptations. It was also purpose built to establish land speed records and the original computers had the chips mounted on the outside so they could be quickly changed. The camshafts are "odd" chances are the engine was "blueprinted " and the intake manifold and ports messaged ,the big question is what if any modifications were done to the crankshaft/oiling which have allowed that engine to run so hard and NOT have #2 and #6 rod bearing fail with no accusump ??
#29
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Just found some reciepts from the prior owner, whom sent both computers back to 928intl, and it looked like the LH was sent back to the customer as good. however, there was mention of the 25pin EZK and the replacement being 35pin, along with the 35pin harness. the LH box was 35pin and was found good and reinstalled. all the boxes had the "G18" designator, as well as the chip handwritten numbers noted. ( i posted what was on the EZK, but now i have the numbers for the LH, which i havent touched since i got the car)
So, it looks like the EZK was conversion from the 25pin to the 35 pin. ON a shop workorder,there is some mention that with the new harness, not all the pins line up correctly. Hmmmmm. what does this mean!! glad i found this out now, after 3 full seasons of racing and lots of dyno runs, showing nothing really wrong with the running of the engine! I guess this means that I dont have knock sensors and probably not that cam sensor as well, right?
still digging. (topically)
MK
So, it looks like the EZK was conversion from the 25pin to the 35 pin. ON a shop workorder,there is some mention that with the new harness, not all the pins line up correctly. Hmmmmm. what does this mean!! glad i found this out now, after 3 full seasons of racing and lots of dyno runs, showing nothing really wrong with the running of the engine! I guess this means that I dont have knock sensors and probably not that cam sensor as well, right?
still digging. (topically)
MK
#30
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Hi Mark,
Very interesting history ! Maybe the software and hardware design for the 35pin EXK was not finished when the Holbert car left the factory ?
It would appear that originally the car did not have knock sensors, or a Hall sensor. Perhaps these were retro -fitted, along with the new wiring harness and standard EZK box.
Very interesting history ! Maybe the software and hardware design for the 35pin EXK was not finished when the Holbert car left the factory ?
It would appear that originally the car did not have knock sensors, or a Hall sensor. Perhaps these were retro -fitted, along with the new wiring harness and standard EZK box.