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Discussion Starter · #1 ·
So I have a built Gen 3 motor we put into a 2014 truck I have the computer and harness for a 2002 tahao my question is it possible to use both computers one to run the engine and one to run the trans ect
 

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‘01 Silverado 2500HD 8.1/Allison 5sp xcab long bed
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No. The same computer has to be able to talk to the engine and the transmission.
 

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Discussion Starter · #3 ·
We have the complete harness out of the Tahoe is there a way to join the 2 harness and run it off of the same computer I really need to make this work it's for a friend and he needs his truck back
 

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Discussion Starter · #4 ·
No. The same computer has to be able to talk to the engine and the transmission.
Long story short a kid that works for me truck blew the engine his dad had built a Gen 3 back in the day and bolted into a Mazda b2000 its 3 to 400 hp stall converter the whole nine it sat for years kid blows his 2014 truck up but has this engine that has mabye 40 miles on it sitting motor pops off with the msd stand alone kit needs a new carb now it' in a newer truck still have the stand alone kit can put a carb on it and make it run but want to use the fuel injection so has anyone ever tried this got built tyranny and stall converter I can add to the project but just trying to make it run nit in limp mode as it sits it won't fire cause the knock sensors are not hooked up and the extra sensors I'm thinking 2 computers since they make it easy now and it's a small harness under the hood power and ground to that harnesses let the new harness fire the engine and the factory harnesses work the throttle body
 

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‘01 Silverado 2500HD 8.1/Allison 5sp xcab long bed
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You will probably be able to get the computer wired to the engine, but that’s not going to run right without some custom programming. What engine is the donor?
 

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Discussion Starter · #7 ·
You will probably be able to get the computer wired to the engine, but that’s not going to run right without some custom programming. What engine is the donor?
It's a 5.3 out of I think a 2002 truck I think the kids dad built that motor and stuck it into a Mazda b2000 several years ago when the motor went in the 2009 we pulled it to the shop and yanked both motors it didn't work because the Gen 4 has dod and different style knock sensors I wound up buying a complete 5.3 and transmission for another friend who lost his transmissions so worst case I have a 2002 intake injectors wireing harness everything from a ls swap project I bought someone out of and I'm not going to use any of that when I stroke this 5.3 and build it to go in my 2002 4wd that currently has a 4.8 so why can't I change computer and the harness from the Tahoe I know it will have to be tuned due to the mother thumper cam that's in the motor
 

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Don't worry about the program, it will have to be changed anyway.
Use a computer that will "talk" to all of the sensors that your using.
The injection system should be the same parts, the spark timing should be the same parts. The DOD/AFM can be programmed out if you use that computer.
then use the wiring harness that goes with the computer and the engine.
you may even find the 2 computers are the same part number, just different programs.
 

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Discussion Starter · #9 ·
Don't worry about the program, it will have to be changed anyway.
Use a computer that will "talk" to all of the sensors that your using.
The injection system should be the same parts, the spark timing should be the same parts. The DOD/AFM can be programmed out if you use that computer.
then use the wiring harness that goes with the computer and the engine.
you may even find the 2 computers are the same part number, just different programs.
Thanks I will post updates when I can get that harness dug our and hooked up going to use the one that fits the sensors cause the problem with the dod harness is it has 4 extra sensors in different places and the sensors that are in the same place won't plug up so let me dig the harness out and see if we can get it to pop off so ready to hear that mother thumper pur
 

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With a bit of a cam and probably a little extra displacement, you might need to upsize the injectors; but they may be fine if the program just keeps them open a little longer.
 

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Discussion Starter · #11 ·
With a bit of a cam and probably a little extra displacement, you might need to upsize the injectors; but they may be fine if the program just keeps them open a little longer.
It has the mother thumper cam and bigger springs whole bottom end is eagle I honestly dont know exactly what John put into it but it's fully built already with about 40 miles don't think he done bigger valves or ported it know it sent that b2000 pretty hard with a big holly on top
 

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Discussion Starter · #12 ·
Ok so luck has it I got that extra motor to build for my truck cause the harness plugs up got it to idle today with the newee model harness plugged into the throttle body and into the mass air flow and sensors on the intake (trying to use the new style tps and intake so petal sensor works and I don't have all the injectors for the older vortec style intake or fuel rails) it idles with both computers but when I hit the gas it dies not communicate with the pulse of injectors to compensate for the throttle to air mix I assume but if I don't use new and old harness the transmission won't shift right and those 4l60 don't like abuse what do I do
 

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Discussion Starter · #13 ·
With a bit of a cam and probably a little extra displacement, you might need to upsize the injectors; but they may be fine if the program just keeps them open a little longer.
The harness I'm having to try to run the motor on doesn't have a obd port they cut it when they striped the motor everything that went inside the tahao was cut I know what wires went inside the firewall finding out wich were obd port can wait until I make the throttle and the injectors work and transmission shift I have idle now that is a plus
 

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Discussion Starter · #14 ·
Keep in mind guys I'm taking a motor that was converted to stand alone carburetor and trying to put a newer style intake and injection on it that come from a different project where I dint need the harness and computer and putting it into a truck with a newer style transmission I have a built performance transmission with 3500 stall that can make my life a hell of alot eaiser but the kid don't have the cash and I like the kid so we are from the make it happen commity
 
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