Just had this conversation the other day with a New to them 04 Ram owner.
1) what's the goal ?
1a) what is the level of Commitment, can you see yourself beating on this truck 5 years from now? reality is once you go down this path the deeper you go there could and will be down time, either waiting on a tune, a part or the dam thing broke.... the 03-08 trucks are more of a labor of love then any of the other Dodge Trucks.
2) the 545 is good to about 500/550 horse, Tow/Haul is your friend, No in Drive Kick down Banzai runs.
3) Weight is your mortal foe, your not going to put a CC 4x4 in to the low12/11s as easy as some one with an ECO boost Fud, a RCSB full body weight high 12s are not that far away...11s with a SBE is not impossible, but it's not cheap and rarely archived.
4) if you can see a lot of Booooooooooooooooost in your future, STOP here and buy a 2012-2014 Ram , it's easier in both short and long-term expenses and headaches.....especially if you find an original 8sp truck.
Comp Cams has put a TON of research in to their G3 Hemi cams, their goal was not only to help the street guys but the street/strip and strip/street guys ...Howards cams are good all round street/strip cams and Crower worked hard on daily driver cams to street/strip guys and the 4x4 boys(girls) Hughes Engines their cams also have a lot of thought and development behind them......MMX is up there when it comes to custom grinds but keep in mind Comp does their cams.
Heads intake , check the post I made to your Eagle heads thread, one thing I forgot to mention in that post is Headers for the Eagle head , there are no off the shelf headers for 09+ heads in the 02-08 trucks.
If someone is dead set on Keeping the older heads PIE is the place to go https://www.performanceinjectionequipment.com/ you WILL NOT find a better flowing 03-08 head,
Headers , they all are about the same till you get in to hand built ones, remember shorties are good for mid range and are a step up on Stock Irons....Long tubes are better yet, and 09 ram Headers will fit in the 02-05s , 06-08 they need some help...next option is to take the 02-08 headers and have someone weld the 09+ flanges on to the 02-08 headers...not hard just a PIA.
Now what I told Jason on Monday (new to him 04 owner) his truck is ST mostly stock , has a set of pacesetter headers , Gibson exhaust system. 3.92 gears and OEM tru track.
The Comp cams 260h doesn't need a tune to run, but it will hunt for Idle once in a while, and you are leaving about 10/15 HP on the table with out a tune. fact is any aftermarket cam with Duration less then 210/212 @ 50 will run in these 03-08 hemi's 03 at the higher elevations .it's bit trickier. with out a tune,,,,the 260H it's about 10-20hp over stock, with out a tune and 30-40 with , a good set of heads helps but not as much as you would think at this early level
, keep in mind stock heads flow about 280-290 CFM @600 lift you only need 222CFM to make 550HP at 6500 RPMs from 345 CI,
Comp Cams 268H, will start and run with out a tune....but Forget idling, it needs help, with a good tuner it'll make some good power, anywhere from 40-65 over stock. food for thought the the 268h has just .006 more lift then the 260 but where it gains is in the [email protected] .50, it's 8 degrees more while both cams have the same CL, the 268H shines when you get up in to the 5500+RPMs below 5000 it's about the same HP/TQ #s as the 260H. slight gains but the 268H really benefits when teamed up with ported heads and any intake other then the stock truck intake.
Notable mentions , Hughes Ser 0812MHLN-14 it's close to the 260H, Lift is higher 540/545 vs 522/525, CL is 114 and it also will run with out a stock tune......but it's lift is high enough that you will have to change the stock style valve seals. that's it's disadvantage over the 260H, but it's advantage is with a good tune it'll get you 268h HP with a stock sounding idle.