D+D Exhaust for EFI Enfields

[ADB]

I received the D&D straight slip-on a few days ago. I placed the order 15 days before it arrived at my door, they're located in TX and I'm in Wisconsin. They actually said it would ship out about a week before it did, and when I called to inquire whether it had shipped, they were very apologetic, and then it shipped out that day.  The total cost, with shipping, was $186.  The box i received included the silencer, a heat-shield, and the pod air filter they recommend adding with the new silencer, (which was supposed to be an additional $35, but for some reason they sent it along w/out charge...maybe for the delay in shipping??).
Anyway I put in on tonight, which was a pretty simple process...the biggest pain was getting the heat shield to fit over the wrap i have on my header pipe; the shield is designed to be almost touching the header pipe.
First impressions: it's definitely louder and a much deeper sound. It's actually not a whole lot louder than the stock pipe at idle, but when you get on it, it's much louder.
As far as added performance, judging from the seat of my pants, it definitely added something here too...I probably only went for a 10 mile loop.  The main difference I noticed tonight was the acceleration in 2nd and 3rd gear, (and back to the sound from the pipe, it's loud enough when you grab a handful of throttle that I'd be nervous doing that w/ a police officer around, I doubt the decibels are w/in the legal limit). 
Anyway, I'm sure I'll post again after i get a chance to go for a proper ride and really get a feel for it, and I'm still unsure whether I'm going to install the new filter...but if i do, I'll let you guys know what that does for performance.
Here's a picture of what it looks like on the bike, not a great photo, taken in my dark garage after I got home from the ride.
I also made a before and after video of how the bike sounded w/ the stock silencer and then w/ the D&D...I was alone, so that was all I could really film. Both of the videos were taken with my bike in the same spot, and shot w/ the same device, so it should be a pretty honest comparison, (i think i must have had my hand over the microphone in the first 5 seconds of the "before" video, so after that is the actual volume of the stocker). 
Before: http://www.youtube.com/watch?v=_wJHHdihXCg&feature=plcp
After: http://www.youtube.com/watch?v=UuYzUoMs0Fg&feature=plcp

[Bulletman]

Great Job ADB and thanks, it does seem to sound a bit more deeper than the stock. 

[rav]

Thanks a lot for taking the time to upload the video, very much appreciated. When you have some time can you attach the pics of the filter setup?

Ravi

[ADB]

I went out for about a 40 mile ride today, and similar thoughts on the pipe...it's loud.  I don't think it's Harley loud, but when i get on it, it's probably closer to that than the way it sounded with the stocker. It's definitely still the thumper sound..but just amplified and noticeably deeper. 
I took a few more pics today so if anyone's interested, they can get a better look at it.
Rav: I haven't even taken the air filter they sent with the pipe out of it's wrapping yet, but in case you're curious, i also took a picture of that and is attached below. 

[ADB]

ok, not sure why the other pics didnt show up in the first post..

[rav]

Thanks, It really looks proportionate to the bike.

[barenekd]

The UNI pod filters are for an iron barrel. The K&N looks kinda small for a UCE. I can't make out if there is a mounting snout on it or not, but if there is, it's for a carburettor, too.
The pipe sounds pretty good, can't really tell if it's too loud or not.
Bare

[gremlin]

I apologize in advance if this has been covered elsewhere ...

Is the header pipe stainless ? or chromed ? 
If stainless, is it available separately ?

[dginfw]

The K&N filter ( the small one) is for the crankcase breather....

[eda1bulletc5]

Hi Folks,

I please need some suggestion;

Can the air filter (uni filter UP-4182) shown in the picture by ADB used by itself directly to the throttle body?

I already have a EFI style silencer/muffler and K&N filter (OEM replacement). There is sometime a backfire that happens - but nothing major.

I am thinking if I can use this Uni filter and the K&N crankcase breather filter (components shows in the picture) then the air filter box could be used as a useful storage area.

Any thoughts how this setup might work for EFI or if anyone tried it?

Thanks.
Sajiv

[Ducati Scotty]

If you put a pod type filter right on the throttle body the MPG is going down.  Mine went down about 20% if I recall correctly.  The bike seemed to run fine but it used a lot more fuel.  For best performance you want to add a length of tubing of some sort.  The theory we've come to is that there's too much turbulence for the manifold pressure sensor to register properly when the filter is mounted right on the throttle body. 

Scott

[gremlin]

this turbulence idea interests me.

IIRC  the MAP sample port is sandwiched between the throttle plate and the intake valve.  The sensor must be built to survive the acoustic shocks from the intake valve closing.  (this incoming charge that has whistled past the partially open throttle plate and is abruptly stopped by the valve closure will rebound back up the intake).

That amount of "noise" in the system would make it necessary to filter the electrical output of the MAP to smooth those thump echos and obtain a nice average value which, when used with the slowly moving TPS signal can be used in a look-up table to determine the load on the engine.

Electrical filters that can smooth the thump echo would have absorbed the relatively high pitched noise of intake turbulence......

I wonder if the improved (lively) throttle response accounts for the reduction in economy.  After all, acceleration is a huge energy waster - and - anything that will make the RPM's lighter and more responsive will by necessity require more energy.

[Arizoni]

Of course I'm just guessing but I think the long intake length just makes for a smooth laminar airflow that moves easily thru the throttle body.

Turbulent air can easily serve to make an invisible dam, effectively blocking off much of the open area to any air that is trying to flow thru it.

There is also the issue of not having enough air in reserve, held in the filter inlet plenum or housing.
If the distance between the throttle plate and the filter doesn't have sufficient volume, the air present is rapidly reduced to a vacuum and only the limited air that can instantly pass thru the filter will be available to supplement the engines needs.

It's rather like trying to take a deep breath from a hose connected to a 50 gallon oil drum vs trying to take the same breath from a similar hose connected to a 2 liter Coke bottle with a small hole in the bottom.

[gremlin]

I agree, too small of a filter will act just like a "choke"

[FiRE Comms]

It's rather like trying to take a deep breath from a hose connected to a 50 gallon oil drum vs trying to take the same breath from a similar hose connected to a 2 liter Coke bottle with a small hole in the bottom.

That's the best description I have heard yet...