LLY FICM

shakenfake

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Sep 15, 2022
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I would not be surprised if it was a multi layer board as those are quite common on boards of this complexity. Plus unsoldering and resoldering those thousand pin chips is not fun even with the proper heat guns.

Now reverse engineering one would make someone a decent amount of cash at least for a short bit. As long as the chips are not proprietary

I wonder how different, really the LB7 FICM is from the LLY. How much work would be required to convert between them.
I have never been in an LLY FICM so I couldn't say. It would be tedious work and not cheap for someone to farm out but it certainly would be better than spending $2,000 on an unknown good used.

It shouldn't matter whether the chips are proprietary or not because you are just replacing the circuit board not creating your own chips.

I am over simplifying this quite a bit though so I am sure there are some things that I am not thinking of at the moment.
 

PureHybrid

Isuzu Shakes IT
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Guys run LLY injectors in LBZs so why can't we do it the other way around? In theory it "should" work as long as the resistances are the same across the solenoids.
I thought the plugs were different. Are you suggesting to cut / wire LLY ends on an LBZ engine harness?
 

Bdsankey

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I thought the plugs were different. Are you suggesting to cut / wire LLY ends on an LBZ engine harness?
I don't see why one couldn't.

Granted, I think doing an LBZ swap just to avoid a FICM is a little crazy if you ask me but that's just my opinion. They're pricey but not unobtainable and they are still being fixed by SIA daily.
 
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2004LB7

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I have never been in an LLY FICM so I couldn't say. It would be tedious work and not cheap for someone to farm out but it certainly would be better than spending $2,000 on an unknown good used.

It shouldn't matter whether the chips are proprietary or not because you are just replacing the circuit board not creating your own chips.

I am over simplifying this quite a bit though so I am sure there are some things that I am not thinking of at the moment.
On the property chips, I was referring more to making "new" boards for customers to cut down on the crazy cost of these used ones. Not necessarily rebuilding the old ones but building ones from scratch.
 

PureHybrid

Isuzu Shakes IT
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I don't see why one couldn't.

Granted, I think doing an LBZ swap just to avoid a FICM is a little crazy if you ask me but that's just my opinion. They're pricey but not unobtainable and they are still being fixed by SIA daily.
It was more of a joke on the LBZ swap.

After talking to the lady from SIA, I'm not sure what issues arise in these FICMs that are actually repairable. If it burns the board, can't be fixed. If it burns the traces, can't be fixed. Processor goes bad, can't fix that either. She told me the board can't be removed from the back peice because it'll break... I've seen videos of people pulling them so IDK if SIA just bullchits people or the things they CAN fix are incredibly easy.
 

2004LB7

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It was more of a joke on the LBZ swap.

After talking to the lady from SIA, I'm not sure what issues arise in these FICMs that are actually repairable. If it burns the board, can't be fixed. If it burns the traces, can't be fixed. Processor goes bad, can't fix that either. She told me the board can't be removed from the back peice because it'll break... I've seen videos of people pulling them so IDK if SIA just bullchits people or the things they CAN fix are incredibly easy.
The latter is my bet
 

shakenfake

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Sep 15, 2022
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On the property chips, I was referring more to making "new" boards for customers to cut down on the crazy cost of these used ones. Not necessarily rebuilding the old ones but building ones from scratch.
Yeah that is what I am talking about as well

Also you can repair traces by doing a jumper but that is pretty hack job tier. Repairing a board or making a new one I don't think is hard. The processor is an entire different thing though.
 

2004LB7

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Yeah that is what I am talking about as well

Also you can repair traces by doing a jumper but that is pretty hack job tier. Repairing a board or making a new one I don't think is hard. The processor is an entire different thing though.
If all it takes is a jumper to repair a trace on a part they want $2k for then I would gladly do it. There are hack ways to pull it off and there are proper ways. a jumper can be done professionally and last just as long

The chips may not be that hard to obtain. The one near the burn in the photo looks to be a Bosch 30421 which google shows as being only a few dollars each.
 

1FastBrick

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Guys run LLY injectors in LBZs so why can't we do it the other way around? In theory it "should" work as long as the resistances are the same across the solenoids.
Isn't the nozzle pattern different on the LBZ Vs the LLY? Not that some one couldn't tune around that part...
 

1FastBrick

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I don't see why one couldn't.

Granted, I think doing an LBZ swap just to avoid a FICM is a little crazy if you ask me but that's just my opinion. They're pricey but not unobtainable and they are still being fixed by SIA daily.
So you think I am crazy... :ROFLMAO:

Actually The FICM has nothing to do with Why I am swaping mine.
Yeah that is what I am talking about as well

Also you can repair traces by doing a jumper but that is pretty hack job tier. Repairing a board or making a new one I don't think is hard. The processor is an entire different thing though.
I used to solder in jumpers on a board that was 4K to replace when the trace would burn out. Did a few on a rotary joint that was proprietary and was about 10k our cost... We also had to order them 10 at a time or they would not build them....
 
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Bdsankey

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Isn't the nozzle pattern different on the LBZ Vs the LLY? Not that some one couldn't tune around that part...
I believe so but look at how many guys use LB7 pistons in 01-16 builds. Same with aftermarket pistons, they're 01-16 typically and not model year specific as the bowl size/shape and CR changed many times throughout the years.


Does it make a difference? Probably, but it seems to be small (could be wrong). I've never personally ran LBZ spray angle nozzles on LB7/LLY pistons but I would bet my house someone has.
 

1FastBrick

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I believe so but look at how many guys use LB7 pistons in 01-16 builds. Same with aftermarket pistons, they're 01-16 typically and not model year specific as the bowl size/shape and CR changed many times throughout the years.


Does it make a difference? Probably, but it seems to be small (could be wrong). I've never personally ran LBZ spray angle nozzles on LB7/LLY pistons but I would bet my house someone has.
I was under the impression the bowl was relatively similar? I thought they changed the pin size from 01-05 Vz. 06-up and coated the skirts
 

Chevy1925

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I was under the impression the bowl was relatively similar? I thought they changed the pin size from 01-05 Vz. 06-up and coated the skirts
the dia is the same on the pin but iirc the design is a little different. nothing major. 06 and up did have coated skirts but we all know they are different pistons overall compared to 01-05.
 

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
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I got the FICM back from SIA today. For some reason they scribed a number on the outer case, I cracked it open again and the board looked the same.

As soon as I find a viable replacement and don't need a "core" I'll let 2004LB7 tinker with it since he offered first
 
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PureHybrid

Isuzu Shakes IT
Feb 15, 2012
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I got your message. Dallas is on vacation so when he gets back we'll work out a deal. I still might keep an eye out for a decent priced one to send off and see if it can be "upgraded" somehow. Even if I put a good one in my truck and get it running, it'll be rolling around in the back of my head constantly and idk if I can trust it like I used to...

I tried to pull up LLY to LBZ swaps and supposedly Russ has a thread on it, but when I searched Google the link to his thread from another won't pull up. I'll post it > https://www.duramaxdiesels.com/forum/threads/lb7-to-lbz-wiring.27198/
 
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