The resonator is straight-thru and has little > no back pressure.

 

Nice illustrative pics, Joe...

Even if as you suggest, interesting to me that the res canister on my FX4 6.2L (common exhaust to all non-Raptor) is 14" long whereas same on Raptor seems prox half that. Of course, also differences in inlet/outlet diameters between those, but seems to me cumulative effect might well be "less is more"...

 

So, you are still running the stock exhaust, but replaced the resonator with a straight piece of pipe?

 

man I wish I could, but here in Cali with the random smog stops, id probably end up with my truck impounded

 

Ruling-out/ignoring the diameter difference (2½" versus 3"), IMO the length difference (Raptor's shorter) relates to the purposely, engineered exhaust note - more throaty-er.

But hey, that's my story and I'm unanimous on that.
.

 

My ecoboost came with resonator delete and stock exhaust from the factory, it's just a little bit louder than others I have heard with the resonator.

 

My comments in post #12 in reply to Joe's illustrative pics were after time underneath my truck making measurements and observing overall layout of the OEM FX4 system. I've posted before about my desire for a complete Raptor system with fit compatibility questions on that early in the eval process.

After extending time watching Craigslist ads using Search Tempest but not finding anything within driving distance, I finally placed a C-L WTB ad, got a response this weekend and now have an S-Crew Raptor system agreed to purchase prox 90 miles "down the road". Hope to get that on Tuesday and installed later next week.

In any case, no resonator-delete for me 'cus my bias is towards maintaining what FoMoCo engineers developed for Raptor. Running w/o a res-pipe tempts resonant frequencies to have their way much like a "kazoo effect". Yes, I'm looking forward to hearing just a little more 6.2L rumble but also figuring that RWHP will be increased compared to the necked-down system otherwise equipped on all non-Raptor trucks. Even w/o adding a tune chip, I'm thinking this change will be noticeable by my "seat of the pants dyno"...

 

I doubt an exhaust will give measurable power increases alone. But add a tune and it should...

 

Congrat's on your find. Me - Purchased a *new* take-off (there's not even any soot in any of the pipes and everything is all shiny) for (IMO) a reason price exhaust system delivered (-free-).

Agree (even though currently have the 2½" resonator-delete from FoMoCo), but alas the *new* take-off that was purchased did not include the intermediate pipe (a.k.a. resonator). For now, I'm waiting for a $8 2½" OD inlet / 3" ID outlet adapter. I'm spending the wait time polishing the exhaust system. Down the road I will probably bite-the-bullet and get the Raptor's intermediate pipe. *Blew my extra $$$ on a pair of GIBSON Ceramic Coated Matte Black Stainless Steel, 2½" inlet / 4" outlet tips ....

 

I think you missed my point? If my truck and a Raptor were both tested on same dyno (assumption on each engine BHP being identical), my expectation is that the Raptor would win in torque and peak HP. All I'm doing is ditching the restrictive exhaust meant for smaller displacement engines and unleashing all the 6.2L goodness w/ no other changes. A tune would likely void warranty on my truck - no thanks...