The longer the tube, the better the scavenging that takes place. For best performance get the longest headers that fitment and your local laws will allow.
Technology is pretty close from one maker to another, but what separates the best headers from the also rans are the quality of materials and welds, as well as the quality of the ceramic coating, and whether it's coated inside and out or just on the outside. IMO you don't get them coated, you are throwing your money away.
Headers are another one of those mods where the cumulative effect with other mods yields more gains from them than just them by themselves. In concert with the right air intake and muffler, a set of LT headers can sometimes produce up to 40% more HP & Torque than the headers alone...

 

Hey Hammer, thanks so much for the info. I talked to the shop today and they said they would install resonators on both sides, in front of the mufflers. They said that should cause enough back pressure to correct the problem. Does that sound accurate to you? Does that sounf like an okay fix? Unfortunately, I'm kind of out of my league here.

Thanks again!

 

resonators ain't the way I'd do it, that's a sound baffle, basically and a resonator, or at least the ones I'm thinking of are big, like muffler or cat size. They will be a little restrictive too, that's where the backpressure will come from. They are kinda taking away some of what you went there to achieve. The first thing most people cut out are the resonators. They are probably just gonna cut your back in.
But they are a shop does this every day. I've done maybe seven or eight of my own cars/trucks and about that many for friends. I'm not an expert by any means.
All I can say is let them do it, see if it gets rid of the CEL and you are happy with the performance and the sound, if not, make them get it right.
I still don't know why they just wouldn't put in the non-foulers, might be an emissions thing, same with the sims. In inspection states, they are as illegal as cutting or gutting the cats.
Let us know how it turns out and good luck...

 

I have true duals on my 06 2500 hemi 6sp.

At the time of my conversion, I had to get a new 02 sensor on the right hand side ( before the y pipe ) the mufler shop tried to use the perfectly good 02 sensor, but they broke it, tapped in a new 02 sensor, I have never had a issue with codes.

One item to consider with the hemi ( esp if a 4x4 ) the left hand ex pipe of the manifold has a long bend than runs into the Y pipe, left hand ex. ( transfer case )

I doubt headers will give any performance gains due to the un = length of the ex pipes of the manifold, if you have a 2wd, theis a lot of room to run the ex pipes strait back.

 

After all of the attempted fixes, the problem turned out to be a pinhole in a weld. Back pressure, or the lack there of was not a problem as originally thought. I finally got a suggestion from an old exhaust guru who said that a having a pinhole was the biggest problem he has seen causing a check engine light following exhaust work. Sure enough, mine had a small pinhole at the first weld. We fixed the pinhole and no more check engine light. Thanks for all of the suggestions. I hope this solution will help in the future.

 

shoot, I can't believe the shop did the install didn't check for a bad weld the first time you brought it back there.... Doesn't sound like a very good shop after all, but glad you eventually got it fixed...

 

...glad you got it fixed.. I myself gutted my cats cuz I wanted no restriction in my 3" true dual setup (besides the muffler).. I do get a check engine for the rear O2 which doesn't mean anything (to the pcm) so I'm not worried about it...with my next cmr tune i'll have the rear O2's deleted...