I know the day is going to come that I either want or need to rebuild my motor. I'd plan on using an LBZ Block to start, but the main question is would there be any drawbacks to switching all the engine electronics over to those LBZ? Obviously, I'd need to change the injectors, glow plugs, LBZ ECM, TCM & GPCM, get all the harnesses off the truck (for the TC, Transmission, TCM, ECM, engine connectors), probably would need to use LBZ heads (LBZ injectors won't fit in LLY heads, right?). With DSP in the future from EFILive, I can't think of any disadvantages. The LBZ's are smoother, quieter, I'd get a properly working 6 speed Allison and tap-shift, etc. Just looking for opinions at the moment. I may start collecting parts down the road to prepare for the inevitable.
Switching to LBZ controls?
- Thread starter Cougar281
- Start date
IIRC Guy said LBZ injectors would work with LLY heads with little machine work...i think the LBZ injectors are larger in diameter.
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GMC_2002_Dmax
The Still Master
IMHO,
You would be farther ahead financially to sell your LLY and purchase an LBZ or trade up to one.
Time is money, and all the little things will cost you big time in the end trying to make it work.
You would be farther ahead financially to sell your LLY and purchase an LBZ or trade up to one.
Time is money, and all the little things will cost you big time in the end trying to make it work.
If EFILive had DSP for the LBZ, I would have considered making mine into an LBZ when I rebuilt it.
DSP is worth that much to me I guess, even though my truck stays in the little tune 98% of the time.
DSP is worth that much to me I guess, even though my truck stays in the little tune 98% of the time.
Well, Rick made an LB7 into an LLY, so I don't think that making an LLY a LBZ would be much more difficult, considering the main differences between the LLY and LBZ trucks (electronics wise) are under the hood (addition of GMLAN between the modules). By getting an entire harness from a doaner truck, in theory, there should only be a handfull of wires that would need to be spliced; Class2, +12, ground and GMLAN come to mind. Now switching an LLY (or even LBZ) to LMM would be a whole different story (IE Replace EVERYTHING electronic in the whole truck).
The whole point is I don't want to buy a "new" truck... I like my truck and would rather take the time, energy, blood, sweat and money to make it better. I've already got a 6 speed VB and 06 cluster in my truck, so that's two items down.
If or when I get another truck, it won't be to replace the one I have, but to supplement it as a Badd-A$$ High HP pulling and/or racing truck. My plans for this truck don't go too far past 550RWHP. Maybe 600. I'd like to rebuild the motor so it can reliably run that power.
The whole point is I don't want to buy a "new" truck... I like my truck and would rather take the time, energy, blood, sweat and money to make it better. I've already got a 6 speed VB and 06 cluster in my truck, so that's two items down.
If or when I get another truck, it won't be to replace the one I have, but to supplement it as a Badd-A$$ High HP pulling and/or racing truck. My plans for this truck don't go too far past 550RWHP. Maybe 600. I'd like to rebuild the motor so it can reliably run that power.
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GMC_2002_Dmax
The Still Master
Good Luck with the swap,
I have done a few conversions in my day and motor swaps are easy, it's getting all the little parts that end up costing you.
When you start tracing down complete motors/transmission/harness's and then retrofit them a few wires can drive you crazy, maybe it will be a breeze for you, but for me, it is trade up or stick with what I have.
I have done a few conversions in my day and motor swaps are easy, it's getting all the little parts that end up costing you.
When you start tracing down complete motors/transmission/harness's and then retrofit them a few wires can drive you crazy, maybe it will be a breeze for you, but for me, it is trade up or stick with what I have.
When you start tracing down complete motors/transmission/harness's and then retrofit them a few wires can drive you crazy, maybe it will be a breeze for you, but for me, it is trade up or stick with what I have.
Well, I've already done a PCM swap that people said couldn't be done (I swapped a 96/97 harness and PCM into my 95 Cougar which required a bit of schematic studying and prepwork, as well as a dozen or so extra wires in the dash harness), so I suspect that with complete harnesses, a LLY to LBZ should be no harder... In theory. If/when I go for it, it will probably be when I do a motor rebuild since the LBZ injectors won't just drop into LLY heads.
I was looking at the tunes and noticed on benefit in particular is the LBZ ECM is capable of reading up to 105lb/min MAF airflow, whereas the LLY can only go up to 66lb/min. I recall reading that some are pegging the MAF on the LLY's with Cheetah's.
Not so sure it's a huge performance benefit, but if you're moving say 90lb/min of air, if the MAF can only read 66lb/min, I would think that might throw off the fueling; Isn't the injected quantity at least somewhat controlled by MAF flow?
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I don't think mine reads that high. I'll have to go back and look at some logs, but I want to say it flat lines somewhere around 87 or so.
The stock tune scales up to 77.161367 on the LBZ, but the ECM is capable of reading up to 105.821600, although I'm not sure how you'd rescale the MAF to measure that high. The LLY's ECM is maxed out at 66.
I continued the table out up to the max reading (I guess it's 105), but it would top out at 80 something (like I said earlier, I think it stopped at 87). I guess I didn't really calibrate it exactly, but I don't think the stock sensor is capable of reading that high.