Not wanting to start a debate over whether there's any appreciable loss between a GOOD 2/2 and a GOOD 2/1. I am wondering if there's any documented, factual data about just how much power is lost ? i.e. HP & torque. Yes, there's more pipes out there than Carter has peanuts I agree. I am talking on average and I agree some pipes aren't just average. I am working on a 95" upgrade and with all my readings, the general concensus for a performance build is a 2/1. I talked with one builder today and he's running a 2/2 on his personal bike, he just likes the look of a 2/2 and he suggested not chasing numbers and I agree. In my case, I am running V&H Dresser Duals with the V&H Oval Slip Ons which this builder mentioned are the biggest power robbers out of all te V&H S/O's and he recommended changing over to the round slip ons. A totally different builder strongly suggested going with the V&H Pro Pipe as choice number one OR the D&D Fatcat pipe as choice number two. His theory is you're just not getting everything out of the build you're paying for which makes sense. If I am only loosing ON AVERAGE a couple of pounds of torque and giving up a couple of HP, I'd just as soon change out my slip ons as opposed to the entire system. That said, any real world data anyone know of ?

Thanks
BM

 

You might want to go check out the Bagger Dyno thread...
https://www.hdforums.com/m_300906/tm.htm

 

I think you mean Carver, not Carter. Anyway, I know you want to see a dyno chart, but I'll tell you. What you have heard is correct. I doubt your butt dyno will notice the loss of power from a 2-2. If you were racing, I'd do 2-1, every hp counts then. Other wise, go with what you think sounds/looks best.

 

Thanks Pappy, I'll have a look.

BM

 

Thanks and Carver it shoulda been lol. That's kind of what I thought about my **** dynometer. I know there's a difference and if I were racing, it'd be a much different story.

BM

 

Definitely go to that thread if you want to see every conceivable set up and how it worked out for people. Some folks here will work to try to get every little bit of power outof their engines, while others of us (who can barely count to ten let alone worry about whether it's 99 or 100 hp) just want to be able to accelerate onto the highway easily and look/sound good while we're doing it.

 

Dyno number are a funny thing. Peak numbers don't tell you where the power is coming on and I think that is where your "seat of the pants" dyno will feel the difference between a 2 into 2 vs. a 2 into 1 exhaust. From what I have seen and read, the power curve with a 2 into 1 comes on sooner, typically where we baggers spend our time riding. I have Rinehart True Duals on my RG and with my new build I will be switching to the Fat Cat 2 into 1 exhaust. I really like the sound I get from my Rineharts but want the power I am paying for and with my "Phil Build" I want his flat torque curve too (still grinin'). Can't get that with my Rineharts.

My $0.02,
RJ

 

...I thought that 2-2 just didn't make as much poweron low end, you don'tlose any power, you just don'tgainas much as good 2-1 .. still better numbers than stock.
Later

 

Thanks Rocket.. hell I am not counting numbers and have a hard time counting to 3 let alone worrying about whether I've got 98hp or 101 hp... I agree with the "seat of the pants dyno" for sure. Not sure if I'll go with the Fatcats or the V&H Pro-pipe quite yet. I've been running V&H for years on various bikes and the fit and finish have been outstanding in every case. From reading, I know the folks with the Fatcats are also top notch. I am told the V&H and Fatcats "bring it on power" are developed at different points by Doc1 who will be the builder of choice for my build. Doc's pipes of choice for 2/1 are 1) Propipe and 2) Fatcats in that order... if I remember correctly, the Fatcat is D&D's answer or response to the Propipe....

Boogey

 

When my 06 SG was a 95" Stage II Big Bore (203cams), I ran both pipes; VH duals with Ovals and Fatcat 2-1. The results on MY bike by the same tuner were:

Same torque from 2K-3.5K rpm,and maxed@ 86ft/lb around 3.2K. The 2-1 however stayed above 80ft/lb to 5.5Krpm where the duals fell under at around 4K.

Horsepower was 78HP w/duals and 83HP with Fatcat.

The single biggest difference for me between the two was 5th gear hiway riding and the much more powerful rollon's with the Fatcat. Far less downshifting. That said, I found the Fatcat to be a bit sluggish and less linear in it's pulling than the duals, pre CR bump.

Now with bumped compression via Heads and Woods cams, the 2-1 is working for me the way it has for others. Lot's of low end torque and lot's of high HP and torque.