Which factory computer....

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5.7 hemi

5.7 hemi

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We all know to stay away from the 03 stuff, wish I knew that 6 years ago but I digress. So which computer would let someone have tuning options with a hand held tuner and get the most out of both? I have been kicking the idea around of getting an 05 computer and another harness from hotwireauto.com and re-doing what I currently have to get more control over the engine and trans. Gimme all your thoughts, pro's and cons's!
 
5.7 hemi said:
We all know to stay away from the 03 stuff, wish I knew that 6 years ago but I digress. So which computer would let someone have tuning options with a hand held tuner and get the most out of both? I have been kicking the idea around of getting an 05 computer and another harness from hotwireauto.com and re-doing what I currently have to get more control over the engine and trans. Gimme all your thoughts, pro's and cons's!
Click to expand...

That's what I have, 05 truck.
 
Not to throw a fly in the ointment, but have you considered FAST, AEM, or Megasquirt? A new harness, new computer, and new tune will set you back at least $1500.00, you might want to consider your other options.

FAST and AEM are around 3K and you gain COMPLETE control over your engine. Learning curve is a bit steep, but if you plan to add a blower, turbo, or NOS you'll love the extra control.

http://www.fuelairspark.com/Products/FS-'EFI Kits'-1.aspx


Megasquirt would be a lot cheaper, since you already have the fuel system all you'd need is a cable operated throttle body, the ECM, and a couple of ignition modules. Probably could be done for LESS than the price of the wiring harness from Hot Wire. The Downside? The learning curve is a bit more like a cliff. If you buy a prebuilt ECM from Diyautotune.com it would simplify things a lot and you'd probably still be in it for less than the price of a wiring harness from Hot Wire.

http://www.ms3efi.com

http://www.diyautotune.com

One other possibility, since you have a car that is running, WAIT. HP Tuners has been promising full Hemi tuning capability for 3 1/2 years. As of yesterday they are finally offering tuning capability to beta testers. It might be in your best interest to read through the thread and see if: 1) they are going to support your particular computer and 2) you are willing to wait until it is finally available.

Here's the thread at HP Tuners:

http://www.hptuners.com/forum/showthread.php?t=19609

Hope this helps.

Regards,

Joe Dokes
 
All aftermarket tuners such as fast, aem, megasquirt, etc., are out cause none of them support the trans, I mean NOBODY!! So factory stuff will do and I can always get someone such as B&G to program the computer for what I want and delete what I dont need.

Now I have read that TCI has a trans controller that is for the 545rfe trans, but when you look up what trans it will support, only Ferd and GM trans. So back to factory stuff.

I've found an 05 computer really cheap, so I think I'll get it and save up for another harness.
 
5.7 hemi said:
All aftermarket tuners such as fast, aem, megasquirt, etc., are out cause none of them support the trans, I mean NOBODY!! So factory stuff will do and I can always get someone such as B&G to program the computer for what I want and delete what I dont need.

Now I have read that TCI has a trans controller that is for the 545rfe trans, but when you look up what trans it will support, only Ferd and GM trans. So back to factory stuff.

I've found an 05 computer really cheap, so I think I'll get it and save up for another harness.
Click to expand...

05 is probably a good choice. but look into it a little further as to what else may need to be changed. i wonder if certain sensors would need to be changed due to having different variables between the years
 
The 05 is the best ram PCM to buy. As diablo has full control of trans tuning in 05 and up, nut in 05 there is no MDS toworry about. So it's your best choice. If trans function is nit a concern go with an 04-05. (FYI)
 
Be aware of the 05 computer. Not because it is a bad computer but sometime between 04 and 06 Chrysler began adding "skim key" basically this is like an RFID chip in the key that has to hand-shake with the computer in order for the car to start. For some of these you can disable the skim key IF you have the VIN Number.

So if you get the computer be sure to get the VIN. Basically the computer without the VIN is a brick. Though I'd contact Hot-wire and verify all of what I've written above.

Regards,

Joe Dokes
 
Yeah I heard of that anti theft thing with those computers.
 
whats the advantage of using an 05 over an 04? It seems that most of the tuners out there all say 04-08 on them as being the same functionality. I have an 04 ram computer I intend to use in my transplant but because of costs will be making my own harness out of a stocker.

I talked to Hotwireauto (Chris) on the phone and he basically said that they just (in my case) put a manual transmission tune on the computer and I'd still end up with check engine codes for things like power steering, battery temp, etc. Does anybody know of somebody tuning these things removing or modifying so that I don't get check engine codes? I really want to run a check engine light on the dash so I know if something is amiss.

(I still need to check with hodrodlane.cc and see what they do with tuning)
 
Have you called B&G Performance? I think they can do what ya need. My 03 computer had alot of codes, but after checking them out they were not of concern and finally they all went away without me deleting them. Here's the kicker on that, when I did the tmr mod and swapped out the 6.1 injectors for the 5.7 injectors, I disconnected the battery while I did this, the codes came back. So I wonder if there is a certain amount of ignition cycling that the computer see's and then it realizes that those codes do not need to be shown cause the snsors aren't hooked up. I checked this with my code reader and my hyperpac and they both show the same codes...power steering, battery temp, gauge cluster so on, things that are not even there. So I'm sure they will go away on their own. I also just bought an 05 computer, so we'll see what kind of codes pop up.
 
5.7 hemi said:
Have you called B&G Performance? I think they can do what ya need. My 03 computer had alot of codes, but after checking them out they were not of concern and finally they all went away without me deleting them. Here's the kicker on that, when I did the tmr mod and swapped out the 6.1 injectors for the 5.7 injectors, I disconnected the battery while I did this, the codes came back. So I wonder if there is a certain amount of ignition cycling that the computer see's and then it realizes that those codes do not need to be shown cause the snsors aren't hooked up. I checked this with my code reader and my hyperpac and they both show the same codes...power steering, battery temp, gauge cluster so on, things that are not even there. So I'm sure they will go away on their own. I also just bought an 05 computer, so we'll see what kind of codes pop up.
Click to expand...

may be something with reteaching the computer after the battery was disconnected so many start and runs for it to learn all over.
 
kb67mopar said:
whats the advantage of using an 05 over an 04? It seems that most of the tuners out there all say 04-08 on them as being the same functionality. I have an 04 ram computer I intend to use in my transplant but because of costs will be making my own harness out of a stocker.

I talked to Hotwireauto (Chris) on the phone and he basically said that they just (in my case) put a manual transmission tune on the computer and I'd still end up with check engine codes for things like power steering, battery temp, etc. Does anybody know of somebody tuning these things removing or modifying so that I don't get check engine codes? I really want to run a check engine light on the dash so I know if something is amiss.

(I still need to check with hodrodlane.cc and see what they do with tuning)
Click to expand...

i believe the advantage number one is there is no seperate computer for the trans(or tcm) it is all consolidated. and performance tunes are limited if any at all

chris used to work for hotrodlane. so you'll probably get the same answers.

i found this post to explain better the 05 computer

06-10-2010, 08:38 PM #15
03ramit1
Senior Member


the 03 truck motors had valve spring problems, so knowing that if you get one swap them out for 16 6.1 exhaust springs ($40-$60 at the dealer)and you will be fine. allthough tuning is really limited for the stock computer. the only advantage i see is there is no EGR.

the 04 and 05 were the same but if you want to use a truck computer get the 05 because then you get better tuning options. allthough unless your keeping the factory ram trans, it does not matter for tuning as both have great programmers for the motor stuff, (the 04's have no trans control and the 05's do)

the 06-08 have MDS, witch will not be functional unless you go with a factory computer. but it is easy to swap out the lifters and not worry about mds again. the factory computers have full tunability to them with an aftermarket programmer.

if you want to talk about it let me know i have geen modding the modern hemi since 05 and average a cam/ head swap a month i know the motors really well. if i dont know something i know people who do. I am also an installer for inertia motorsports
 
So, I'm putting a 5.7 Hemi from an 06 Magnum in my Duster....and I have the factory computer that was on my motor. Would my motor have MDS? If so, will I need to add a switch to disable it when the right foot gets heavy? I don't mind keeping the MDS when I get the motor in the Duster if it will help the highway mileage. I'm using a 545RFE from an 07 Hemi Durango.
 
You will need to use the truck computer. The 545rfe trans will need to "see" the truck computer and will not work with the car computer.
 
JDMopar said:
So, I'm putting a 5.7 Hemi from an 06 Magnum in my Duster....and I have the factory computer that was on my motor. Would my motor have MDS? If so, will I need to add a switch to disable it when the right foot gets heavy? I don't mind keeping the MDS when I get the motor in the Duster if it will help the highway mileage. I'm using a 545RFE from an 07 Hemi Durango.
Click to expand...

Besides what 5.7hemi said no, you don't need a switch. The computer uses throttle position and engine load to determine whether or not to de-activate the cylinders...so if you want to keep it go ahead but use the truck computer with the 5-45rfe.

Thanks again guys. I didn't know you couldn't have the trans tuning options with the 04. I have the 04 but am going with a manual trans anyway so it should be fine.
 
I wonder if I send my computer to Street & Performance, if they could reflash it to make the 545RFE work? I know these are dumb questions for you guys that have fooled with the new Hemis a lot, but I'm still in wide open learning mode :banghead: LOL
 
JDMopar said:
So, I'm putting a 5.7 Hemi from an 06 Magnum in my Duster....and I have the factory computer that was on my motor. Would my motor have MDS? If so, will I need to add a switch to disable it when the right foot gets heavy? I don't mind keeping the MDS when I get the motor in the Duster if it will help the highway mileage. I'm using a 545RFE from an 07 Hemi Durango.
Click to expand...

There are a number of other inputs that the LX computer needs ( like wheel speed sensors ) in order to use the MDS. If you use a LX computer it will not control the 545, you have to use a truck ecu. Damned if you do, and damned if you don't.....
 
Ok I'll try and be brief here. All this is in reference to truck pcm's as I know more about them than the cars, as it's mainly all I do.

03 PCM is the bastard PCM, tubing can be done via hypertec, or superchips. Forget running cams nitrous blowers turbos ect. Your limited to canned tunes and shift point changes. This would be fine for someone wanting a stock motor as a daily driver, or someone running headers and wanting just a little more pep and throttle response.

04 can be tuned the same as above, but with the added benefit of the diablo. The drawback though is no option for trans tuning via diablo but if your running a 727 or manual this is not a concern. But the trans functions need to be removed from the PCM.

05 introduced trans tuning via diablo and just about killed the market for hypertec, and superchips. (as there was no advantage to them) the same for running a non factory trans still applies as it will from here on out. The 05 was alot heavier(I don't know an exact number I would guess about half) into the skim (anti theft key) although it was an option in 03-04. (about 10% is my guess) my personal opinion is it would be the best PCM to use. (unless you want MDS)

06-08 were all just about the same. All had MDS, all have trans and custom tuning via diablo. And are a great choice if you keeping MDS, if you want to eliminate it you have the ability in diablo to turn it off. (if say you had an 08 PCM and 04 motor) if you have an MDS motor and turn it off there is no need to swap the lifters, just keep it off if you don't want it, (now if you have an MDS motor and a non MDS PCM you will need to change lifters, as the PCM cannot control them)

I hope this helps a little and clears the air a bit. Thanks to the wonderful Ma mopar, it makes it a little confusing. They changed PCM configurations more often than most people change underwear.

To answer a few question off the top of my head, no the LX PCM will not work with the 545 trans, there may be a way arround it but it will require more hair pulling than it's worth buying a ram PCM.

Next the 09-12 motors are not compatable with the 03-08 PCM and most parts are not enterchangable. Rods crank and pistons maybe but that's about all. The blocks, accessories, heads, intake manifolds, ect are diffrent. Yeah the heads will physically bolt on, but due to combustion chamber shape and piston design the 09+ heads will yield a compression ratio so high 116 or better race gas would be required. Unless you do your research just keep 03-08 and 09+ separate.
 
03Ramit and Tincup.....thank you for the great replies. :prayer: Looks like I've got something else from an LX to sell.....lol. There's a big truck/suv junkyard nearby, so hopefully I can buy an 06-08 pcm there to tell my motor what to do. Street & Performance will probably shoot me in the face when I tell em I have an LX Hemi, an suv 545rfe, and a truck PCM! I bought my 545rfe at the same junkyard I'm going to for the PCM, so maybe they will have the PCM that was in the Durango my transmission came out of. It was an 07 Hemi Durango 2wd. Thanks again for the information. You probably saved me from a costly mistake.
 
Excellent post by 03Ramit,

The only thing I'd add is that the 09 and later heads will bolt on to the early 03-08 blocks and do greatly increase the CR as he said, BUT if you are building a custom motor, the 09 and later heads flow much better than the 08 and earlier heads. The 03-08 Heads flow about 268 CFM while the 09 heads flow about 295 CFM.

Thus, the stock 09 heads flow nearly equal to the stock 6.1L heads and will bolt on, while the 6.1L heads can't be bolted onto the 5.7L block. Also the 09 and later heads have the same port size and shape as the 6.1L heads so you can bolt the 6.1 intake manifold directly to the 09 heads, without the use of epoxy and or gasket matching of the 5.7L heads.

But keep in mind, that as 03Ramit said, unless you dish the pistons you'll get crazy high compression.

Regards,

Joe Dokes
 
New to me 05 computer will be next week, and I'm looking into getting the Diablo Intune, should be a good combination.
 
Just got my 05 computer, gonna hook it up and turn the key, hopefully the fuel pump will kick on, that way I have an idea that it works before the warranty runs out in 120 days, plus I'm curious. Also the new to me 6.1 manifold will be here next week, gasket set also. I'm now running twin 4 inch air intake tubes, got the air intake dirt cheap at the march meet at Famoso, still waiting on the 4 inch silicone adapters. Diablo Intune is next on the list, but waiting for them to get control of the trans before buying, alot of guys are pissed cause Diablo said trans controllast year and they still dont have it yet. Then order a new harness and I should be good to go.
 
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