hemi wireharness cut/splice ?

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03ramit1 said:
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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I've never wired a megasquirt no but I've done more then enough research to know what I'm talking about. Depending on where the OP lives it's not as simple as taking it to a tuner to get tuned. I know where I live there is nobody to help you tune a megasquirt. I have several Hemi engine harness' I purchased for 20 bucks from salvage yards that could easily be used with a reflashed pcm. I can buy a pcm for 200 bucks from the local salvage and send it out and get it flashed for 100 bucks. Done and done. People overreact when it comes to this stuff and end up finding the hardest route in an effort to "save money" I myself have 3 car pcm's and 5 truck pcm's. they are very easy to come by and cheap if you have the contacts.
 
After reading and reading and reading...god it never ends.
I am leaning towards the Megasquirt setup. I think its gonna be the best choice, FAST is just way to damn expensive, fall back would be hotwire.
 
4dr4ever said:
I've never wired a megasquirt no but I've done more then enough research to know what I'm talking about. Depending on where the OP lives it's not as simple as taking it to a tuner to get tuned. I know where I live there is nobody to help you tune a megasquirt. I have several Hemi engine harness' I purchased for 20 bucks from salvage yards that could easily be used with a reflashed pcm. I can buy a pcm for 200 bucks from the local salvage and send it out and get it flashed for 100 bucks. Done and done. People overreact when it comes to this stuff and end up finding the hardest route in an effort to "save money" I myself have 3 car pcm's and 5 truck pcm's. they are very easy to come by and cheap if you have the contacts.
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Contacts, man I can get parts for 2012 cars, to 2000 cars just about anything you could want I can get it for my own personal use for free. A really good buddy of mine runs a private salvage yard. (not open to the public, and therefor a much better quality of parts) I am broke and will still not go that route. Tuning is an issue with the stock PCM. (yeah yeah diablo this and that) I'm sorry but I wanna control cylinders not banks. Tuning is not hard. People are just scared of it.
 
snapetwo said:
that is true, but a grand for some wires? come on.
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Considering I used to build stand alone harnesses for VW's and Hondas and I chose to have Hotwire do mine is a good indication of what time is worth. It is a huge undertaking and in the end you have a nice clean harness. If something is wrong you just pick up the phone and say, "Hotwire, We have a problem"

Just my 2 pennies.
 
But it's still $1000. I have from 2 in the afternoon until 10 every night to tinker around. And honestly, seeing how it's for fun. If it takes 6 months it doesn't matter. I get it time is money too, but some people have an abundance of time and very little money. While others are just the opposite. so giving more than the typical just buy the harness response make it known of other possibilities. My car has not been touched in about a year, as my play money ran out. (had to take on a car payment when my daily driver died) and now living for paycheck to paycheck and barley getting by, the car has had to sit. There are small things that will be done once it cools off, and hopefully I'll scrap up enough money to buy an oil pump pickup tube, throttle body, radiator, trans rebuild kit, remote oil filter kit, fluids and a driveshaft. Then I may actually be able to start this car after all it's going on 2.5 years since the project was started. It would be mice to stop pushing it.
 
Actually it was only $995 including my transmission wiring. ;)

I understand you point and agree.. For me I had to buy a harness regardless because the idiot cut the harness on my motor. Figured if I was gonna shell out a couple hundred on a harness why not just bite the bullet and get a plug and play deal. My big factor is time, I am always busy and my weekends are booked full with kids. The other factor....... I'm an electrical engineer and now doing all the wiring just makes me feel like I am at work!
 
Personally, I've chosen to go the MS3 route. As others have already chimed in the pros and cons I can tell you by the time all is said and done, MS3 is only a little cheaper than reprogrammed unit from Hot-Wire. The key benefit to MS3 is that you have complete control of the fuel and spark in your motor. For those wishing to change cams, run forced induction, staged nitrous, or anything out of the ordinary, MS 3 offers a level of tune-ability beyond the factory harness.

That being said, you can modify a factory harness and get it to work in a classic muscle car. There are a couple of keys to making this work.

1. Get EVERYTHING from a single donor. Motor, trans (if your going that route), and every harness you can lay your hands on, un-cut, un-molested. Personally if I were going to go this route, I'd get a truck motor from and 05 or 06. Get the under dash harness if you can as well as the under-hood harness. The factory gas pedel can only be used once, so simply get the wiring up to the pedal.

2. Determine if your engine utilizes a SKIM key. The skim key is an anti theft device built into the key. Think of it as an electronic hand shake that must occur between the key and the computer before the car will start. No Hand Shake, no start. If the car is skim key equipped get the key, and the dash wiring. You'll need to incorporate some of this into your wiring harness.

3. Be sure to copy down the VIN number off the car or truck you can't fiddle with the computer without the VIN. Think of it as the combination to the lock.

4. Get a copy of the FACTORY service manual, they are available online cheap.

5. Print out all the wiring diagrams. (You might want to buy a laser printer. Ink Jet printers cost about 22 cents a page to print vs. 4 cents for a laser printed page, YOU'LL be PRINTING A-LOT)

6. Trace each and every wiring coming into and out of the PCM (power train control module)

7. Slowly but surely mark the wires you THINK you won't need. Wire by wire eliminate the wires. What I'd do is get a pin extraction tool and pull the wire, and simply tape it off until your SURE you won't need it.

6. Test fire the engine. Does it run?

7. If it runs, plug in a code reader, and check for error codes. If your code free, you can remove the wires from the harness, simply unwrap the harness, remove the wire and set it aside. Don't cut it you might need it later.

8. A note about "reprogramming" most reprogramming simply involves using the factory service tool to switch off a bunch of options in the computer. You can buy a factory service tool on E-Bay for around $4000.00. (now you know why, Hot-Wire charges 250-400 to "reprogram" your factory computer.

Finally, here's a guy who did modify a factory wiring harness TWICE. Read through his build and you'll get some, though not all the info you need to do the job.

http://www.forabodiesonly.com/mopar/showthread.php?t=53074

Regards,

Joe Dokes
 
I have done exactly what you are considering using a 5.7 engine and 545RFE transmission from a 2005 Dodge Ram 2500. I got all the wiring with the engine and trans so I decided to give it a try.

If you have the skill and time I personally think it is definitely worth the cost savings. For some they can spend more time at work make more money and spend it on their project. For me I can spend more time doing the work myself to allow me to spend money on other parts of the project and get the car on the road sooner.

I had to read the factory service manual wiring diagrams to determine where each extra wire comes from and goes to then add the appropriate fuse, relay, power source, ground, etc. connection. I basically laid all the wiring out in a spare bedroom and worked on it off and on for a couple hours at a time in the evening during the course of one winter. Would I do it again? YES! Would I recommend it to others? For most people that would answer would be no. I have a good friend that is a mechanical engineer that would never have the patience for it, but for me it was a relaxing escape from work. It ultimately depends on your skill level and what you like to do. Do you like challenges and want to spend time learning how to read and decode the wiring diagrams? If so then go for it. If not, just buy one.

To get your car running you need all the wiring harness that connects to the engine and computer. There are four plugs that connect to the computer for the engine and transmission. For me alot of the cutting and splicing centered around wires that went through the stock truck's fuse and relay block. Lots of wires were removed in the process.

Not all computers have the security. Luckly mine did not so I have not had it programmed yet and currently the only trouble codes that come up are for no gauge cluster, no ABS speed signal, and no rear O2 sensors. I added resistors to a few circuits to trick the computer into thinking things like the fan relay, cruise control are still present.

Here's an older post with a summary of the circuits that I needed a fuse or relay for.
http://www.forabodiesonly.com/mopar/showpost.php?p=1105896&postcount=47
 
Thanks guys. That helps a bunch.

All I have is just the engine out of a 05' ram. No harness to speak of and no computer.
So I would need to get a harness outta a junker and a computer.
Just debating...Maybe in my case, paying for the plug n play everything you need system is the best option. but money is a factor as always.

I do have the time to do this, versus being able to work more...

Real question just comes down to, "spend money to get the system complete and ready to go NOW, or try and hunt down an intact wireharness, hack/splice it, get a computer and all that computer stuff too"

choice I gotta make at some point.
thanks again.
 
Shoot me a pm, with what factory parts you need and I'll see what I can scrounge up.
 
U can get a 05 ram ecu on line for $100 then buy Hotwire plug and play harness for $995 the a gas pedal for $100 and ur done. This is exactly what I did. Have it tuned with diablo predator there are tons of ppl that tune with this software, good luck finding a tuner with ms set up.
 
USCG CHARGER said:
U can get a 05 ram ecu on line for $100 then buy Hotwire plug and play harness for $995 the a gas pedal for $100 and ur done. This is exactly what I did. Have it tuned with diablo predator there are tons of ppl that tune with this software, good luck finding a tuner with ms set up.
Click to expand...

+1
it's easy enough to find a local yard with an ECU and if you try hard enough you can get the pedal that is calibrated right to that ECU. Really shouldn't be to much difference in calibration but hey if you need both why not get a matched set.
 
Look online I've picked up 2005 ECU for $100, hotwire auto sales the pedal it's $100.. there is no calibration needed.
 
If you use the stock ecu you wont be using a cable tb. as all factory stuff is drive by wire.
 
I know of several 1.4's in the 60's with 4000lb challengers, chargers, 300's, and Magnums that are obviously drive by wire. Trust me there is no lag in my set up.
 
USCG CHARGER said:
I know of several 1.4's in the 60's with 4000lb challengers, chargers, 300's, and Magnums that are obviously drive by wire. Trust me there is no lag in my set up.
Click to expand...


I think he means lack of pedal feel, but if the OP was to get in a drive by wire vehicle without being told and drive down the road the gas pedal feels no different then any other vehicle
 
The last two new cars I've owned have been drive by wire. In the first case, I didn't know until the check engine light came on and I began to do some research. In both cases throttle response was excellent and the system responded well and immediately to my input.

The only downside is that in most cases you can't power brake a drive by wire setup. The computer sees both the brake and gas being applied and will close the throttle plate regardless of the fact that your foot is on the floor.

This is a safety devise, if the computer thinks that the gas pedal might be stuck and the driver is putting on the brake is shuts the throttle. Toyotas DID NOT have this feature until AFTER the throttle scare (which was probably 99.9% driver error).

There are pros and cons to both the factory ecu and MS3. If you can pick up the correct harness and computer for a couple of hundred bucks total, it would be well worth your time to try to figure out how to do it. MS3 is pretty cheap, but in the long run it is comparable in price to a Hot Wire harness and one of their reprogrammed units.

Best of luck,

Regards,

Joe Dokes
 
Joe Dokes said:
Personally, I've chosen to go the MS3 route. As others have already chimed in the pros and cons I can tell you by the time all is said and done, MS3 is only a little cheaper than reprogrammed unit from Hot-Wire. The key benefit to MS3 is that you have complete control of the fuel and spark in your motor. For those wishing to change cams, run forced induction, staged nitrous, or anything out of the ordinary, MS 3 offers a level of tune-ability beyond the factory harness.

That being said, you can modify a factory harness and get it to work in a classic muscle car. There are a couple of keys to making this work.

1. Get EVERYTHING from a single donor. Motor, trans (if your going that route), and every harness you can lay your hands on, un-cut, un-molested. Personally if I were going to go this route, I'd get a truck motor from and 05 or 06. Get the under dash harness if you can as well as the under-hood harness. The factory gas pedel can only be used once, so simply get the wiring up to the pedal.

2. Determine if your engine utilizes a SKIM key. The skim key is an anti theft device built into the key. Think of it as an electronic hand shake that must occur between the key and the computer before the car will start. No Hand Shake, no start. If the car is skim key equipped get the key, and the dash wiring. You'll need to incorporate some of this into your wiring harness.

3. Be sure to copy down the VIN number off the car or truck you can't fiddle with the computer without the VIN. Think of it as the combination to the lock.

4. Get a copy of the FACTORY service manual, they are available online cheap.

5. Print out all the wiring diagrams. (You might want to buy a laser printer. Ink Jet printers cost about 22 cents a page to print vs. 4 cents for a laser printed page, YOU'LL be PRINTING A-LOT)

6. Trace each and every wiring coming into and out of the PCM (power train control module)

7. Slowly but surely mark the wires you THINK you won't need. Wire by wire eliminate the wires. What I'd do is get a pin extraction tool and pull the wire, and simply tape it off until your SURE you won't need it.

6. Test fire the engine. Does it run?

7. If it runs, plug in a code reader, and check for error codes. If your code free, you can remove the wires from the harness, simply unwrap the harness, remove the wire and set it aside. Don't cut it you might need it later.

8. A note about "reprogramming" most reprogramming simply involves using the factory service tool to switch off a bunch of options in the computer. You can buy a factory service tool on E-Bay for around $4000.00. (now you know why, Hot-Wire charges 250-400 to "reprogram" your factory computer.

Finally, here's a guy who did modify a factory wiring harness TWICE. Read through his build and you'll get some, though not all the info you need to do the job.

http://www.forabodiesonly.com/mopar/showthread.php?t=53074

Regards,

Joe Dokes
Click to expand...
I hate to tell you this man, but the factory ecm is capable of more control and more power than 99.9% of people out there could ever want or need.

The MS3 is a real bear. After setting up ms3 cars I can tell you it takes an expert and they cost 5 times as much to get programmed correctly. Any cam, blower, turbo, stroker motor you can make run on an MS3 or other aftermarket setup I can probably make run better on the factory EFI.
 
USCG CHARGER said:
I concur with u Brian
Click to expand...

Hey, You remember when we were talking about building you a 5.7 single turbo for your LX? I am building THAT motor and putting it in my Polara. Steve can be kinda difficult to work with sometimes, but I thought it was a awesome idea and I am going to try for the 1xxx rear wheel number with a single 78 and a stock CID 5.7. I will let you know how it goes. I have a thread over in the b body forum
 
mops_050057_dyno_03_z.jpg

http://www.moparmusclemagazine.com/techarticles/mopp_050057_dyno_torquing_hemi_intakes/photo_03.html
 
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