cheapest way to get hemi 3g going?

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snapetwo

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Ok, so now that mopar has agreed and stepped up to help us all out with swaps. I see that they have a complete stand alone engine kit for 6k...not happening.

I already have the engine. I need a wire harness, and ecu. then i can at least fire the engine and make sure it works...i can deal w the cable and stuff later.

Ma' Mopar has a wire harness for $700.
Hotwire Auto's harness cost $1000
then you gotta buy a computer, the fully programmable from Ma'Mopar is $2200.
Hotwire will flash one for $700, less if you buy their harness.

then there is all the extras, throttle body, pedal, etc etc.

so what is the cheapest route?
and making my own harness is not an option, not with out a full work up. step by step.
 
New ecm ( they use a 05 truck pcm) , wiring harness, and a new dbw pedal, you are looking at $1756 shipped from Hotwire.
You could find a used ecm to save a few bucks.
This would be the cheapest "plug and play" setup brand new that uses all the factory sensors including the DBW throttle body.
 
Absolute Cheapest?

Depends upon how much work you're willing to do yourself.

I've seen guys buy a junk yard motor with a factory computer and harness and use a factory service manual and make their own wiring harness.

I've seen guys cut up a truck pan and weld it back together rather than buying a Milodon unit.

I've seen guys fabricate their own headers, rather than buy a set of TTIs.

I've seen guys fabricate their own motor mounts.

Doing all of the above can save thousands.

Here's the route I'm going, you'll see that it is "relatively" inexpensive:

1. Bought a used 6.1L Hemi along with the engine wiring harness off of Craigslist. Found it relatively cheaply at 4K.

2. Built a Megasquirt Computer to handle spark and ignition. I built mine saving over $100.00. When all is said and done, you'll have about $1000.00 in the computer and wiring. You'll have to make your own harness but it is a lot simpler than modifying the factory harness to work in a classic car. Is it "step by step?" No but it is pretty close. Megasquirt is about 1/3 the cost of FAST or AEM.

Here's some other threads regarding Megasquirt with a lot more details:

http://www.forabodiesonly.com/mopar/showthread.php?t=137216

http://www.forabodiesonly.com/mopar/showthread.php?t=169167

3. Bought an 85mm Gm LS cable operated throttle body on eBay for $100.00. It was a good deal, but they can be had all day long for about $200.00.

4. Made an adapter to attach the cable operated throttle body to the 6.1L Hemi intake manifold. $20.00

5. Will be buying the Milodon oil pan. $300.00 Charlies oil pans and Canton also make oil pans but they are more expensive.

6. Will buy TTI motor mounts. $250.00 I have spool type mounts. Biscuit mounts are $133.00

7. Will buy TTI Headers $750.00. If you are installing a 5.7L Hemi you can save a lot buy using stock Jeep Cherokee manifolds. Obviously long tube headers are worth more HP, but the Jeep manifolds can be had for 1/3 the price.

8. Use a filter / regulator from a 2000 Corvette about $75.00.

9. Use an external fuel pump from DIYAutotune.com $110.00

10. Oil Filter relocation kit. Prices vary.

11. Other fuel system mods. Prices vary.

As you can see the dollars add up pretty fast.

I DO NOT WANT TO START A DEBATE ABOUT THE PUTTING A CARB ON A GEN III HEMI, BUT if you are trying to get the motor in the car and running as cheaply as possible, an Indy mod-man intake with 650 Holley and MSD Hemi 6 Controller is probably the cheapest way to go since you save so much on the fuel system, and you probably know someone with a Holley laying around.

Regards,

Joe Dokes
 
Thank for the info.
ya, with an idiots guide to wireharness hacking....that is not an option for me. Just don't have the skills.
As far as Carb, no way. That is the whole point of the new hemi, efi.....so no efi, no sense in putting it in.
 
Given the parameters that you've mentioned. Not wanting to hack the stock harness, not wanting to run a carb. The hot-wire setup is probably the cheapest and easiest way to go. You might save a few bucks finding a computer and having hot-wire program it, rather than buying one of theirs.

At just under 2K it is slightly more expensive than Megasquirt but it is basically plug and play. A bunch of people on this site have used the Hot-Wire solution with good results. Customer service seems to be good and the overall quality of the product is excellent.

AEM, FAST, and Megasquirt all have a pretty steep learning curve. Yes, AEM (sold under the Mopar Performance brand), and FAST come with a starter tune. But as others have figured out these tunes need a lot of fine tuning to work beautifully. A thread I read online (not first hand knowledge so take it with a grain of salt) from a guy who used the FAST setup claimed that he had to spend over a $1000.00 to have his car tuned after installing a FAST setup on a 6.1L Hemi.

Now that was a few years ago and now FAST uses a wide band O2 sensor and has a self-tuning feature, this should greatly reduce the need for dyno time. Although at over 3K, probably out of your price range.

Save your pennies.

Regards,

Joe Dokes
 
Found this.
[ame="http://www.youtube.com/watch?v=U_y4xuIVajQ"]9-29-12 how is Megasquirt wired into a car - YouTube[/ame]

my basic understanding from this video and others...
1. need something to fire injectors (megasquirt).
2. need something to fire spark (msd box)
megasquirt picks up signal from TPS, few other sensors and can tell the injectors when to fire.
MSD does its thing some how and tells coils to fire.

Now those running carb setup, say they have to have an MSD box too cuz there is no distributor and its pretty much just plug and play.

So what makes this harder? I'm sure im grossly over simplifying this process....but why do i need to get a harness hacked and what not? can't I just plug megasquirt into the fuel injectors and get it working?
 
I would recommend running Megasquirt for all of it. Fuel and Spark.
 
Im not all smart in this, its really beyond me...but how can i do megasquirt for spark? From what ive read, it cant fire the hemi coils?...hence the MSD boxes?
Would be nice, cuz MSD requires 2 boxes, about $600 a piece
 
ya, came across that.
So tell me, I get that MS3...what exactly do i need for wiring? I mean i am going to be doing my own thing for the car itself, So I just need an engine harness right?
Then its just splice the MS3 into the fuel rails, sensors...fire that thing up?

obviously there is more things, like fuel and what not. But the engine and computer are taken care of. No needing to spend money to have it flashed, just plug it into my laptop.
 
In order to get Megasquirt to work with a 2003-2008 5.7L Hemi you need to do a couple of things:

1. Convert the drive by wire throttle body to a cable operated throttle body. FAST sells an adapter for $68.00 that will allow you to bolt on one of their 92mm throttle bodies. I made my own adapter, all you really need is a drill press.

2. You need use a GM style throttle position switch and a GM style Idle Air Control valve, with the FAST throttle body as it is an LS style throttle body.

3. At a minimum you'll need to use the following stock sensors:
Intake air temperature sensor.
Coolant temperature sensor
Camshaft position sensor
Crankshaft position sensor
You can use the stock wiring harness to connect to a pigtail you buy from DIYAutotune.

4. The MS3 and MS3X do not put out enough juice to fire the factory coils, unlike the Chevrolet Coils which have built in ignitors, the Hemi Coils need an external ignitor, so you will need two of these:

http://www.diyautotune.com/catalog/quadspark-four-channel-ignition-module-p-481.html

This should get you thinking.

Regards,

Joe Dokes
 
Thanks joe. I think I may give this a try. Definitely thinking that's for sure.
I do like the idea of having ms3 be the ecu, and be fully programmable.
And not for the $2300 mopar wants for a programmable ecu
 
Joe,
Another issue I'm seeing is gauges and throttle kick down.
Getting something to convert the dbw to cable is fine, but how about the kick down for transmission? I am thinking of going w a 6 speed, but if i go auto, i need a kick down.
but the bigger issue, Gauges.....how does that work?
Granted I am not using the stock 05 ram gauges, and I am not opposed to doing something with different gauges...just thinking "how do i get signal" to them.

I can understand all of this in "theory"...but as to getting down and soldering in resistors and know what pieces to put together...beyond me at this point....I really need to get off my butt and get that EE/CE degree already.
 
More megasquirt info:

http://msextra.com/doc/ms3/quickstart.html

My first idea was to use a computer for my gauges (fed by the megasquirt computer). I scrapped that idea, and now I'll be using 'regular' aftermarket gauges with their own sensors.

No need for a degree for all this. Just time spent studying and working.
 
Lokar makes a kickdown assembly.

For oil pressure and engine temperature simply insert a T fitting into the block and use both the stock sensor and the classic sensor.

As for a tach, MS has a tach output that works with most aftermarket tachs.

Regards,

Joe Dokes
 
HA....degree applies more to my interests, despite how it looks, I do enjoy electronics, playing w wires, soldering, etc....just wish I knew more about the "antequated" stuff like building boards....
I am actually a network admin( associates only), for for HP......but I find myself wanting more of the ins/outs of the electronics....and i need a BA for better jobs and pay.
Figured "CE/EE would apply for me"
 
I bought my board pre-assembled from diyautotune.com

They asked a few specs from my build, and built it for me. I also bought their harnesses with 10 foot length or whatever. And I have a junkyard harness off a hemi (~$100?). I'll splice it all together, use tunerstudio to set everything up per the directions from diyautotune, and I expect it to work. The only 'difficult' part of the process should be the wiring and choosing the right settings in tunerstudio.
 
Ya, thats what im thinking too. thats just to much work for me to try and solder and ive never done a board.
This is the stuff that makes me scared and just want to go to hotwire auto, and go that route...dunno what the pros/cons really are.
 
Just use the hotwireauto set up and then get a trinity or intune and have a cmr tuner dial it in for ya.
 
I built my own board. It took quite a while, probably about 4-8 hours total. If you can read and follow directions it is actually pretty easy, just like eating an elephant, ONE BITE AT A TIME. I was really scared, I didn't want to make a $400.00 paper weight. I took my time, followed the directions very carefully and everything turned out great. Also building the box taught me a lot as well, so I think as an exercise it was well worth the effort.

I'd suggest you do what I did:

There are two test boards for the MS3 and MS3X they plug into the DB connectors on the outside of the box. Both of them come assembled or in kit form. They are both much simpler to assemble than an actual Megasquirt.

I ordered both:

http://www.diyautotune.com/catalog/jimstimx-expansion-board-unassembled-p-473.html

http://www.diyautotune.com/catalog/...imulator-wheel-simulator-unassembl-p-174.html

The JimStimX is the easier one to build. I built that, then built the JimStim, The JimStim even has a built in self test, so you can test the tester!

Once I built those two, I felt pretty confident to build the MS3.

One other important factor, there are A LOT of parts but they come very well organized in neat little bags with very clear labels. If you were the type of guy that could build a model and have it look like the picture on the box then you can do this. :cheers:

Even if you buy a prebuilt box, you're going to want to build or buy a simulator as it helps with diagnostics. It also allows you to work out any connection issues you might have with your computert. I use all Macs so connecting to MS was a bit of a challenge. I had to download some specific USB and Serial driver support. If I was trying to do this while sitting in the front seat of the car it could have been really never racking.

Also, the cool thing about the tuning software for MS is that since it is written in JAVA it is fully mac compatible, neither the FAST or AEM systems are, I'd have to run Windows through boot camp, with yet another expense.

It's also really fun to hook the MS3 to your computer and play around with all the pots and watch the needles move. Kind of like a video game without the explosions. The MS3X simulator has LEDs that represent each spark event, and each injection event so you can watch the flash of each injector and spark plug fire. The inner nerd in me thinks it's pretty cool.
 
I decided to go with the hotwire because you are getting a factory ecm, and all the driveablility of a new hemi car in your musclecar. Plenty of stock ecm srt cars on LX forums running 400 whp with just a cam upgrade , I have a friend with a stock srt challenger with a vortech supercharger putting 570 whp with a tune and still getting low 20's gas mileage. These engines with factory efi are a great balance of power and decent mileage. Got my brown box a while back from hotwire:


IMAG0412-1.jpg
 
I keep sitting on the fence over this, ha.
1. Hotwire i can buy it, its premade, uses factory ECU, don't need to tune it(or as much?)
2. Megasquirt, gotta make it all, lotta work, doesn't use factor ECU, needs tunes which appears to not be so easy for a new guy to the game.

not seeing pros really for this MS3, seems its a lot of work and hacking, to make it work, versus just going to hotwire and buying their product.

Other then cost, but that seems to be minimal too from these posts.
Am I missing anything?
 
snapetwo said:
I keep sitting on the fence over this, ha.
1. Hotwire i can buy it, its premade, uses factory ECU, don't need to tune it(or as much?)
2. Megasquirt, gotta make it all, lotta work, doesn't use factor ECU, needs tunes which appears to not be so easy for a new guy to the game.

not seeing pros really for this MS3, seems its a lot of work and hacking, to make it work, versus just going to hotwire and buying their product.

Other then cost, but that seems to be minimal too from these posts.
Am I missing anything?
Click to expand...

Reasons for MS3x:
If you're a DIY guy
If you want to tune it yourself
If you like saving money by doing it yourself (wiring, tuning, etc)
If you're doing something radical with the hemi (hilborn injection, etc)

Reasons for factory computer:
If you're running a stock motor, or something with very little done
If you don't mind paying a little extra to have a true OEM quality product with knock control and all

The gray area is if you're running a boosted motor. The stock computer tuners have done a very good job with it, but I understand there are still some part throttle boost issues. I'm sure some will refute that- I have no first hand experience, so that's all I can say on the issue.
 
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