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Discussion Starter · #1 ·
I saw a post that stated you can tune an 03 hemi.... does this mean you don't have to convert an 03 ram 2500 hemi pcm over to an 05 pcm? I did not do any upgrades to my truck yet but I do want to do some to squeeze a little more out of it. Could you recommend any simple yet effective upgrades that will aid in towing at highway speeds. "12,000 pound trailer" that would not require a pcm change and any tuning needed could be done with the stock 03pcm?
Not looking for massive gains but just a little help with the towing without sacrificing daily driveability. Definitely need more than a simple cold air intake lol.
Your advice is greatly appreciated. I have about 2grand to throw at it now. Like to stay close to that.
 

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Red Trucker
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Depends on the cam. 03 PCM is VERY limited. If you're looking for more torque without going through the swap, drop a 260 with a set of 6.1 exhaust springs and a full set of 6.1 I&E pushrods and call it a day. Maybe a timing chain. It will run on a Superchips 91 canned tune but you can custom tune things just a little bit. Any cam wilder than that and you're outta luck on the stock 03 PCM.
 

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Discussion Starter · #3 · (Edited)
Thank you for the advice, hopefully you can give me a little more. With the engine out, I will do the cam upgrade as I've heard that recommendation before, as far as upgrading to the 6.1 push rods and springs will any year 6.1 work "I assume so but as they say assumption is the mother of all F-ups" and will this take care of the dreaded dropping valve issue?

Is the superchips 91 you recommend a simple plug and play or do I need a program along with it or flashing to the pcm?

And lastly With all that getting done plus opening up the exhaust a bit "thinking headers" with cat removal, adding a decent cold air intake will the truck still run nice or is all of that combined going to be too much?

Any idea of a rough estimate of the hp or torque gains I would see? Hate to see no real improvement getting up to highway speed with 10,000lbs behind me.

Any input on gear changes in the rear and front diff? Heard MANY people in other forums suggest going to 3:73 or 4:56 ratios.

Many thanks
 

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Red Trucker
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Thank you for the advice, hopefully you can give me a little more. With the engine out, I will do the cam upgrade as I've heard that recommendation before, as far as upgrading to the 6.1 push rods and springs will any year 6.1 work "I assume so but as they say assumption is the mother of all F-ups" and will this take care of the dreaded dropping valve issue?
The dreaded valve dropping issues isn't as widespread as everyone seems to think......no one ever talks about the bulk of the trucks that are just fine, you only ever hear about the failures (I have early 5.7's at a variety of mileages over 100k including one that was over 180k when it got wrecked, all on original valvesprings).
Yes, any year 6.1 will work fine, but to reiterate (reread my original post), it needs to be 16 6.1 EXHAUST springs. You cannot use the 6.1 intake springs. For the pushrods you can use any year 6.1 and THOSE are the full set of intake & exhaust rods. There's a reason for these specifics. 6.1 exhaust spring is the same height as the pre-eagle 5.7 spring (intake is not). 6.1 pushrods are longer because the 6.1 cam has a different size base circle and all aftermarket cams use that base circle.

Is the superchips 91 you recommend a simple plug and play or do I need a program along with it or flashing to the pcm?
It's a handheld tuner. Plug it in, choose your options, load the program. If you can find someone to do a little custom tuning to tailor it better for the truck, that's always better.

And lastly With all that getting done plus opening up the exhaust a bit "thinking headers" with cat removal, adding a decent cold air intake will the truck still run nice or is all of that combined going to be too much?
Headers good, removing cat you definitely won't find any custom tuner who will touch your truck with the recent EPA crackdowns on defeating emissions devices.

Any idea of a rough estimate of the hp or torque gains I would see? Hate to see no real improvement getting up to highway speed with 10,000lbs behind me.
Google Comp Cams hemi 260, I'm not gonna do ALL The work for you lol.

Any input on gear changes in the rear and front diff? Heard MANY people in other forums suggest going to 3:73 or 4:56 ratios.

Many thanks
You have a 3rd gen 2500 that is not a Power Wagon, therefore you have 3.73's already. Your only real option would be 4.56's and that has to be front AND back (which get expensive quickly).

If you didn't have a 2003 I'd tell you to put in a stroker 5.7; what that big heavy truck needs is displacement. Mopar didn't really figure it out until they released the truck 6.4 in the 4th gen HD (took long enough) and they overengineered that thing.
 

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Discussion Starter · #8 ·
That was great advice. Thank you for taking the time to answer.
I'm a little bummed about the removing the cats and not having anyone to tune it afterward, especially if I do go with an upgraded pcm. All of this stuff going and I was thinking.. has anyone stuffed an 8.1 vortec into a ram 2500? I do have one of those laying around with 92,000 miles on it out of my old 3/4 ton suburban.
 

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Discussion Starter · #10 ·
I'll be posting this in a new thread also but since you were very patient I'm hoping you could shed light on my upcoming decision.
Could either option be done for around 4k. With everything working "dash, speedo, etc etc"

The goal is 425+ HP and 600+ torque.
Daily use, towing 10k loads weekly on highway. I want to keep the stock trans and t-case.

Keep the 5.7 hemi but upgrade pcm to an 05 with harness modification, install new cam, upgrade heads "springs,pushrods,etc", cold air intake, and decent custom tune.

Toss in a lightly modified DT360 engine "fuel pump and injector upgrades", yes I know some frame adaption and drive shaft mods will be needed" , adapter plate for transmission, relocate oil filter, try and find a wire harness adapter, tuning or programing as needed.
 

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Stu
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4.56 gears, long tube headers, free flowing exhaust system, 260 cam, 6.1 valve springs, ported heads, cold air intake, Superchips/Diablo tuner, ATS stage 5 545rfe trans with a Edge Pro Torue 2800 stall tc is a good start.
 
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