lowh07
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Is that a bad idea?
What did you do to your NNBS GMT900 Tahoe/Yukon Today?
- Thread starter phattyford
- Start date
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Is that a bad idea?
swathdiver
Full Access Member
Well, it's not a plug and play swap Dave. Originally, you could not get the older system to talk to the new system but I have read on the Performance Trucks forum that adapters are made for this now. I do not know what problems those new harnesses will solve and what else will be needed to make this a seamless operating system.
What year is your Tahoe?
lowh07
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2007 (might technically be a 2006.5, it’s one of the firsts). I know people put LQ4s into anything and everything so I never thought of it being an issue. Was thinking I could/should maybe use the original harness. It’s going to be a learning experience and never expected it to be plug and play. I’ve never heard of a gen III in a gen IV being a dealbreaker
Also did I ever post my name here or something lol. I don’t see it on my profile, and I don’t care at all if anyone calls me Dave or David, just wondering Lol. Might be fb friends with some people on here too. If anyone wants to add me I’m David Ramsey and my profile pic is with Cleetus
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swathdiver
Full Access Member
I'm viewing this on my PC and your name comes up. Gen III does not use Canbus architecture and their computers cannot talk to Gen IV computers. The Gen IIIs crankshaft has a 24 tooth reluctor which is not compatible with Gen IV computers which rely on a 58 tooth reluctor. You can swap cranks or reluctors nowadays I hear. Then there is the aforementioned harness that I was told about but do not remember reading about it.
Just spent 5 minutes googling, I'd rather run a 6.2 than the old LQ4 with all the work involved. Not even sure that 4L80 will work either.
I'm just the first to come along, these fellas have forgotten more than I'll ever know on this topic.
Where's Chris? @iamdub Where's Randy? @randeez
@91RS @Tonyrodz @fasteddy @1BADI5 @Scottydoggs @01ssreda4
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No pics of the black face, please, someone seeing it (out of context) will be offended. Not that I care if they are.
No pics of the black face, please, someone seeing it (out of context) will be offended. Not that I care if they are.
Yes, Just Fishing's chances at that Supreme Court nomination would be toast.
08z71bgm
Full Access Member
Those are what’s on the gen4 5.3
oh and incase anyone wanted to know, 799 heads have 64 cc combustion chambers.
I just confirmed it with my Cylinder head cc kit.
08z71bgm
Full Access Member
What is your dynamic?
08z71bgm
Full Access Member
Does anyone know a website that has the cfm of many if not all factory radiator fan assemblies?
Just Fishing
Can't fix stupid
Too high!
I'm going to lower the static down to what a 6.2 truck has...
Damn, i wish i did more thought into this build
I need pistons with little 4cc valve reliefs in them.
If i went with a sloppy quench i would be ok, but i want a tight quench!!
gooffeyguy
Tom
08z71bgm
Full Access Member
What is the the dynamic compression ratio? Too high is not an answerToo high!
I'm going to lower the static down to what a 6.2 truck has...
Damn, i wish i did more thought into this build
I need pistons with little 4cc valve reliefs in them.
If i went with a sloppy quench i would be ok, but i want a tight quench!!
Just Fishing
Can't fix stupid
08z71bgm
Full Access Member
For the record I was considering 799 heads on a 6.2 to raise the compression for an N/A build and a cam and my static was 11.5 by dynamic was 6 and was safe to run pump gas. Change your cam if you don’t have enough bleed off.Too high!
I'm going to lower the static down to what a 6.2 truck has...
Damn, i wish i did more thought into this build
I need pistons with little 4cc valve reliefs in them.
If i went with a sloppy quench i would be ok, but i want a tight quench!!
mistake it was 8.7 and was safe enough for pump gas.
swathdiver
Full Access Member
I looked a few years and could not come up with anything, only aftermarket. The only measurable data was the wattage of the electric motors, 500 or 700.
Just Fishing
Can't fix stupid
says i'm at 9.29 dynamic
could be a little off, i used some general settings for the calculator.
I have a stock 6.2 camshaft from a gen4.
Just Fishing
Can't fix stupid
yeah more $$!
I don't think i can return the camshaft at this point since it's in the engine.
but it's a possibility still...
i'm going to try and increase the chamber size, but in the end i might end up at the machine shop for another wait.
We shall see how motivated i get this weekend!
Just Fishing
Can't fix stupid
Tonyrodz
Resident Resident
Just Fishing
Can't fix stupid
Pull your bits from the old engine and put on the new engine?
Only real problem i see is that reluctor wheel on the crank...
I heard rumors about an adapter to make it work, but you loose a bunch of resolution.
and I don't know if the knock sensor location will be an issue or not...
What I'm doing with mine.
Took the 5.3 crank, rods, heads, intake, etc.
got 4in pistons and rings, had the assembly balanced with a brand new GM 6.0 block.
I have 799 heads, and apparently they are somewhat desirable for low end.
(low end is what i really want from the hoe)
And looking at the chambers, they match up perfectly with a 4in bore!
(more so once I'm done)
basically since my truck is an 09, I'm using an 09 trailblazer SS with the 6.0 as a template.
The trailblazers 6.0 used 799 heads, exactly the same intake, and throttle body and injectors as my 5.3
from there, i took a base tune from hp tuners website for that trailblazer ss and did a little copy paste of the values.
transmission settings, i took from an escalade base tune since the pressures are a tad higher than the base 5.3.
can't wait to see if it works...
I'm hoping i won't need a tuner right away.
if it came down to it, you always could yank the crank and see if a machine shop could swap the reluctor wheel.
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