2 into 2 or 2 into 1 exhaust??
Seasoned HDF Member
Joined: Jul 2008
Posts: 9,282
Likes: 1,139
From: southeast PA
Most will say that the 2:1 will give more hp and tq. A lot of it depends on your setup and how well it is tuned. Either way, I don't think you're talking about a huge difference so you should get the system you like- how it looks and sounds will matter more to you than 2 or 3 hp. Unless you're talking about racing it.
Outstanding HDF Member
Joined: May 2008
Posts: 2,166
Likes: 4
From: la
I think a lot of exhaust claims are overrated, with stock cams the difference is minimal. When I switched from V&H Sideshots w/BCT QQ's to a Supermeg w/20 disc closed it felt better in the bottom end but the dyno showed I lost a little TQ and HP, the open cap took care of that though, it was a different dyno and operator so it wasn't a true comparison. I vote for get what you like.
Road Captain
Joined: Jul 2009
Posts: 586
Likes: 1
From: Falcon, CO
2 to 3 hp difference, is thats a joke? 2-1 makes about 20% more HP and TQ over the 2-2 and I have the dyno graphs to prove it between two identical bikes (wifes and mine) with the same AC, Tuner, Dyno and Dyno operator (stock engine besides the AC and exhaust). 2-2 did not make more HP or tq, what it did make came on early and fell off VERY quickly! Look at the HP curve of the 2-1, its still making HP at red line while the 2-2 is flat and its torque is falling on its face.
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Road Warrior
Joined: Apr 2009
Posts: 1,360
Likes: 4
I don't think so, from what I've heard most say max HP is from 2-2 but at high RPM, more torque from 2-1 but at low RPM. So 2-1 are typically better cruising but are also notorious for mid range power dips.
All exhausts for these bikes are too short to be that effective. They are more different in style and sound than power making. To get the most out of them you also need to tune.
General rule of thumb is to buy an exhaust based on style or sound. Slip ons and the stock header with a proper tune get you as much max power within 1-2% as any exhaust. But if you have to have that last 1%, go with the 2-2 and a pro tuner.
Anyone claiming 20% difference is not tuning properly, IMHO.
All exhausts for these bikes are too short to be that effective. They are more different in style and sound than power making. To get the most out of them you also need to tune.
General rule of thumb is to buy an exhaust based on style or sound. Slip ons and the stock header with a proper tune get you as much max power within 1-2% as any exhaust. But if you have to have that last 1%, go with the 2-2 and a pro tuner.
Anyone claiming 20% difference is not tuning properly, IMHO.
Last edited by ColdCase; Nov 21, 2010 at 01:52 PM.
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Road Captain
Joined: Dec 2009
Posts: 646
Likes: 1
From: Rockford, IL
IMHO I think 2-2 sounds much better than 2-1. I absolutely love the sound of my V & H big radius. 2-2 have more of a choppy exhaust note at idle...considering you are hearing each individual cylinder firing as opposed to having both pipes merge together.
Road Master
Joined: Dec 2008
Posts: 868
Likes: 30
From: western north carolina
Received bike with the V&H straight-shot slip ons. Changed to the big radius 2 into1. The butt dyno says no big change in engine response. Don't race it with no one or with a clock so who cares about max rpm range. The slip ons were loader if that counts, and they were baffled. Must say I like the looks better with the big radius so they are here to stay for awhile anyhow.