hemi wireharness cut/splice ?

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snapetwo

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Ok, i'll admit im a little dodo bird here with this wiring and the new hemi.
I keep hearing everyone say you gotta splice, and cut and make a harness, etc etc.

What exactly has to be done to the harness? In my mind all I see is needing to splice the wires into your existing car harness..ie brake lights, headlights, radio, igintion..that kinda stuff (some might not even be related)

Am I missing something? or are you having to, for a lack of a better word, having to "hack" the wiring to make it run?

Ok now if that is the case, I don't see it as beeing so hard.
now my personal situation, I am no stranger to wires. i do IT work, don't make me an electrical engineer by any means, but im not scared to splice adn solder and whatever.

Also, my car as is, is going to need to be completely rewired anyway, as the guy who had it before me hacked the hell outta the wires...i don't even have an engine harness right now.

If anyone can clear this up a bit, I would appreciate know what EXACTLY is needing to be done.

Thanks
 
I can't say for sure since I ended up going with a full aftermarket computer setup, but I think the main thing you have to worry about it figuring out power and stuff to the factory computer. The sensors shouldn't need any changing pinout-wise, but you may need to shorten/lengthen the wires as needed to reach where they need to go. You will need to figure out what lines need constant power, switch power, ground, etc. I would think. I think some of it too is just cutting out the parts you don't want/need. You can keep the stock harness for lighting and stuff and just have the factory computer run the engine I think. Hopefully someone else will chime in with some more exact info.
 
Appreciate the input. I am hoping its simple. Hell i dont' have a computer or harness right now, and the dart isn't wired with the original wiring harness either...clean slate right now.
 
I guess my big question is...Why can't I just go get a computer outta a 2005 ram, plug the hemi in it, and start it?
WHAT NEEDS TO BE CHANGED?!!!!!! ARGGGG
 
call hot wire @ 479 243 9115 they do wiring harness for hemi convertions and can answer your questions. and ask about your controler bonehead.....good luck sound like fun
 
ya, i talked to them already. They want $2000 for a computer and harness, for that much money I may as well take a crack at it myself.
 
snapetwo said:
ya, i talked to them already. They want $2000 for a computer and harness, for that much money I may as well take a crack at it myself.
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The harness from Hotwire was a plug and play setup. Only had to hook up about 5 wires and it was running. I know it is a lot of cash, but you have to choose your battles...
 
Figure out how much time you will spend going thru every wire, (got a book of the wiring schematic?), and total that up. If it takes ya 10-15 hours at your hourly rate (just use what you make an hour for comparision) and do the math. You might be amazed at how reasonable it is, plus you know it works.
 
that is true, but then i figure my hourly rate (aint much btw...thank you IT), then subtract my bills, im left with a weekend and whats left...and if it takes me 15hours thats fine, it took my like 40 hours to do the front suspension(granted i screwed off alot and had to wait on parts)....but thats the point, to do the work, even if alot of time.
besides, I gotta wire the rest of the car anyway, as it has NO wiring
 
Ok so putting it bluntely.
IF I get a 2005 wireharness for my 2005 hemi, and a computer outta a 2005...and i connect it all up. WILL IT FIRE? least enough to tell me if the engine works?
 
snapetwo said:
Ok so putting it bluntely.
IF I get a 2005 wireharness for my 2005 hemi, and a computer outta a 2005...and i connect it all up. WILL IT FIRE? least enough to tell me if the engine works?
Click to expand...

not likely because dodge vehicles have a transponder key; it will just start and run for 5 seconds and die
 
5 seconds though...? and if i get it flashed, that would take care of the key thing right? haha...I just don't want to go through all this trouble and money to find out the engine is a dud
 
snapetwo said:
5 seconds though...? and if i get it flashed, that would take care of the key thing right? haha...I just don't want to go through all this trouble and money to find out the engine is a dud
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yes its s security feature, but it costs quite abit to have the computer flashed, seems to me there is other programming that needs to be dones as well but I'm by no means a hemi specialist
 
I know of the security feature, I have an 09 charger...and I WILL NOT BEING USING THAT "KEY" ON THE DART. ha.
I know a place that will flash the computer for a $100, hotwireauto...im thinking they have that in there "tune"..

thanks for reminding me though, as I totally spaced it.
 
I can help you with all your engine harness and computer issues. Hoenstly, I will buy the harness from hotwire auto, get you a ecm out of my pile of ecms, reflash it for you, and ship it. Anyway you look at it though it is going to be $1500.

There are wires required from 3 different plugs on the ECM, in addition to that there are relays that are required as well. Without a schematic and the ability to wire the ecm plugs.....it isnt going to happen.
 
guess at that point im commited w the hemi. If it don't run then, I gotta fix it.

Thanks for explaining a bit more what exactly is needed on the wiring.
 
Funny, I just looked around. I have a 360 block, a 318, and a 5.7 hemi, a 727 and a 904...and still not a one that is in the dart.
 
You can run a hemi6 msd controller and a carb, still expensive.

You can bolt it up to a small block trans.

You wont make the same amount of power, have the reliability, or get the same kind of mileage as the 5.7 hemi
 
Since $$ is an issue (and when is it not for all of us) I would suggest you figure which engine you want to use and go from there. Save the coin, sell off what you have and are not gonna use, get a paper route (lol), do go out to eat 6 of the 7 days in a week, you see where I'm going with this? Take your time, mock up the engine/trans (use your smallblock 727) work on other parts of the car and in no-time the $$ for the harness will be there, then the computer. You can do it, just takes time as all.
 
Why not spend $400 on a mega squirt computer, and harness? Get an engine harness from a salvage yard and put the two together. The engine harness is routed wrapped and already the correct length. It will have a plug on the end that you just need to get the other end of, and wire up the mega squirt to it and your good to go. Then you have full tuning abilitys for anything that may come down the line later (cam heads, blower, turbo, nitrous ect) no need to worry about security, transmission delete, or code forissing body modules ect. It's a simple way to go cheaper than fast, and you can have modern fuel injection. That's a hard to beat combo.
 
03ramit1 said:
Why not spend $400 on a mega squirt computer, and harness? Get an engine harness from a salvage yard and put the two together. The engine harness is routed wrapped and already the correct length. It will have a plug on the end that you just need to get the other end of, and wire up the mega squirt to it and your good to go. Then you have full tuning abilitys for anything that may come down the line later (cam heads, blower, turbo, nitrous ect) no need to worry about security, transmission delete, or code forissing body modules ect. It's a simple way to go cheaper than fast, and you can have modern fuel injection. That's a hard to beat combo.
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Megasquirt is no plug and play simple ready to roll system. I wouldn't recommend it to anyone who isn't ready to dive into it and program fuel mapping and timing etc etc etc. It's way harder then it looks.

Nobody needs to run out and buy a 1000 dollar harness. Buy a complete stock harness and strip it down just to the wiring that runs to the motor. Done flash ecu good to go run power to ecu and starter.
 
4dr4ever said:
Megasquirt is no plug and play simple ready to roll system. I wouldn't recommend it to anyone who isn't ready to dive into it and program fuel mapping and timing etc etc etc. It's way harder then it looks.

Nobody needs to run out and buy a 1000 dollar harness. Buy a complete stock harness and strip it down just to the wiring that runs to the motor. Done flash ecu good to go run power to ecu and starter.
Click to expand...

Did you not read the op comments? He can solder, is not afrad of a little wireing, and cost is a concern. Have you even played with mega squirt? It's really not that hard. The factory engine harness has a plug that ties into the factory chassis harness on the ram. So if you utilize that plug, and wire the megasquirt to the chassis harness side the factory engine harness will plug in to it. and the wiring is done. You can buy a tested and assembled PCM from megasquirt. As well as the pcm harness.

You can get plenty of help with tuning via megasquirt's message board. There are enough guys running megasquirted hemis that someone is bound to be willing to share a tune file. (that will get you running) and if your not comfortable visit a tuner. Have it dialed in.

I honestly think your saying it's not so easy has more to do with your lack of experience with the megasquirt. I built the PCM myself, they have really good manuals and are easy to follow. I would honestly recommend it to anyone willing to put in some effort and save a few $$$ vs the toss cubic dollars at a car to make it pretty mentality. $1000 is way too much for s stupid harness, then still needing to source a PCM, have it flashed, and then worry aboutnmsking actually fit the car. Seems harder than building a harness from the glove box through the firewall to a factory harness, and plugging it in. Then you have one plug to remove and the engine can be installed or removed. Seems like a better option to me, bit then again I'm not scared of work. I'm broke and cheapest is best for me.
 
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