Comparing 2 into 1 performance Pipes

Most riders that choose performance as their number one reason to choose exhaust seem to go to the 2 into 1 pipes. I am aware of the reasons for that choice, but there are several to choose from. There are Thunder Headers, V&H Pro Pipes HS, the Samson Caliber to name a few. I did notice that the V&H headpipes are not equal length. The others seem to bend the rear pipe to equal the length. Since I am putting these on a "bagger" would any of these work better than the other. Any imput from those who have dyno tested any of these would be very helpful. I am currently running V&H dresser dual head pipes with Hooker Tuned Flow mufflers. Am I going to gain?? I don't mind spending the money if I get a return for it.

When it comes to pipes, everybody has there favorite. Whether its for looks, sound, design, etc. I have always ran V&H pipes. Curently I have a 2004 Road King Classic, with the stage 2 kit and am running the 2 into 1 HS Pro Pipes. They seem to sound good and boost the horsepower a bit. Ride Safe, David.

I also frequently run V&H pipes, but with performance as number one, I was curious why the Pro Pipes have the uneven head pipes, seems like it breaks one of the rules. I started out with V&H oval mufflers and now have the Hookers because they are tunable. But they are loud as hell.

"LOUD"

For some "loud" is not so good. For me, " LOUD " IS A GOOD THING. (As long as ears are not bleeding after a good hard ride.)

Loud is NOT Better!

Tell that to the person who is stuck riding behind you where the volume is much higher than what you hear from the front of the pipe. There is a reason why the general public hates the motorcycle world due to the loud pipes. Now for the technical stuff. In order for a pipe to get the most torque and horsepower in the range that you are going to be riding most of the time you do need something that has restriction (baffles) to get proper back pressure. The reason that a 2 into 1 pipe works so well is that the exhaust pulse from each cylinder aids in scavenging the gases from the other pipe and this will keep the gases from returning up the pipe (reversion). The length of the pipes are designed so they will maximize the exhaust flow yet maintain the proper back pressure by taking into account the harmonics of the exhaust pulses. Thunder Header and Vance & Hines have both done their homework. If you look at the numerous dyno runs published they both are consistantly rated at the top but flip flop position as to who is number one. Both build a very good pipe and you really can't go wrong choosing one above the other. If you are comparing prices, remember that the Thunder Header does not include heat shield, which must be ordered seperatly. Good luck with the new system.

Back Pressure.

Hmmm. First off, I was joking with gunny about his exhuast being loud as hell. Secondly, I DO NOT CARE what citizen John Doe thinks about my "loud" exhaust while he is driving his gas guzzling SUV to his weekly morale majority meeting. Thirdly,I am so tired of people trying to pass off that back-pressure as a good or wanted thing. If back-pressure is a good thing than what is with scavenging or stepped exhaust ? What you want is EXHAUST VELOCITY; somewhere around 300fpm. You can tune your whole power curve by your exhaust. What some people do is buy an exhaust pipe that has an diameter too large and there EXHAUST VELOCITY slows down;which create an illusion that they need BACK-PRESSURE. Now, without getting into the MANY factors of exhaust science; scavenging, reversion, torque cones(back-pressure) sonic-pulse,thermal-pulse,thermal-burn,cam-overlap,length/diameter of pipe, and of couse how many cubic-inches ya got to blow down your pipes, when it comes time to buy, buy an exhaust that will optimize your engine. Just buy the right size pipe.

You make some great points there Killer-B, I like it just loud enough to set off as many toyota alarms at once as I can in the south end of the city on an early Sunday morning ride. My current record is 7 at once, but that was with my 52 Panhead with shotgun fishtails. Anything louder than that is extra. As for tuning the exhaust, maybe I should rely on the local dyno gurus to tune my Hooker tunables on the V&H headpipes to my bike rather than go to a 2 into 1. Any more thoughts on that??

VYBR8R lays it out very well.
I will add a few notes on fit, quality and customer support. On a scale of 1-10, ten being the highest.


Fit and Finish: V&H 8-10 Thunderheader 4-6. V&H sets the standard for quality, fit and finish and Thunderheader has on going issues that need to be resolved.

Customer Support V&H 8-10 hands down the Best in the industry. Thunderheader 0 to -10, down with Samson and below even Hard Khrome. Since Jim Rich jr died, there has been a decided down turn in the customer support. There is no tech line or e-mail response for end users and they charge the dealers freight on damaged or faulty goods both in return and shipping back. As a result, Thunderheaders are not only more costly but, dealers have to account for the additional freight costs they may incur.

Performance is another issue. Do you know that the basic Thunderheader design has not been changed since their introduction more than ten years ago? In 1995 they were hands down the kings of the hill and reigned supreme in the H-D world. Now, they can be considered pretenders to the thrown as several designs have knocked the king off the hill a time or two. They are still a great performer but the hilltop is a little more crowded. V&H, RB, D&D, Hooker and the now defunct White Brothers E series are all contenders.

Equal length headers are generally assumed to produce the best results but there are some variables. EVO's and Shovels like a different optimum length than TC88's do. When I used to build and race small block mopars the primary tube length would vary quite a bit from cylinder to cylinder and brand to brand. A rep from Hooker once told us that some engines require a different primary lengths for different cylinders for optimum results. Also, that there is a range for the length and still be in the 'sweet spot'. A ton of engineering goes into getting the look, fit and still have as much performance as possible.

Now my brain hurts..

Hmmm, so V&H engineers, Samson's engineers, Jim Rich Sr, Jerry Branch, Gerald Rinehart, Denis Manning, ad infinutum are wrong?
Velocity is but one component of exhaust design. An exhaust with too low back pressure will never perform as well as one with the correct back pressure, primary length and diameter. Add the intended use of the exhaust system i.e. street or strip or canyon racing etc into the mix. As you say, there are many variables and while velocity is important it by no means the only factor in design.

As far as Mr. John Doe is concerned? Apparently you have not paid attention to the Colorado Springs fiasco? If you go through there going to Sturgis etc, do not pull off the freeway to get gas if you are not running some real quiet pipes or you are going to get a ticket and either pay or stay. Several states in the north east corridor are equipping patrol cars with the equipment required to measure your exhaust db. The Motorcycle Industry Counsel is being pressured by the EPA and DOT to request manufacturers produce quieter LEGAL aftermarket exhaust. Bub is working on a deflection based design that will be much quieter. John Doe might drive a guzzler but, he isn't the one setting off car alarms and walking up the neighbors. Who do you think the politicians will listen to? We have brought it on ourselves and if we do not start acting more responsible we will be riding lawn mowers again. Talk as loud as you want but California will have a law go into effect that basically outlaws all but stock and CARB approved exhaust soon. Ever hear the saying "so goes California, so goes the USA"?

CD is right about that. The noise issue is getting huge attention these days. The AMA is hot on it as well. I think a stock Harley is too quiet for my liking but the guys running straight pipes that think EVERYONE loves that sound are going to take their toll on the whole motorcycle community. The Hookers on my bike can be loud, but I do keep that in mind and choose when to make them roar. usually when on a back road and not in heavy traffic. CD, this question is for you. Which do YOU think will perform best, the current tunable dresser dual head pipes with the Hookers tuned or put a set of good old V&H Pro Pipe HS pipes on my set up??

Yep.

Hi there gentlemen. Well, l I was kind of joking about ear bleeding exhaust volume. I will say that I am a registered voter and I vote. I read and pay attention to the various motorcycle groups and I vote according to what I think will best benefit motorcyclist in general. With that, I may be wrong but, I will add when you refer to Branch and those guys, I think they are talking about the apparent back-pressure.(The illusion) Like I said, you want optimum exhaust velocity, 300fpm, not much more and not much less. But than again I could haven out of my tree and hit my head again.

i believe it is illegal any where in the usa to alter the emission system of any motor vehicle [exhaust system]

Head Pipe Length

Just an added note about head pipes that appear to be unequal in length... any time a fluid (including exhaust gases) flows in a curved pipe there is additional back pressure compared to flow in a straight pipe. The engine could have the same effective back-pressure from a shorter curved pipe as compared to a straighter, longer pipe. I would guess that the folks at VH and others have factored in the curves to design pipes that are the same effective length though they may be physically different lengths.

Good point breeze. I'd like to think these guys spend a great deal of time designing these things. I've never had Cycle Shack pipes, but my local dealers tell me these are "homemade" type and not particularly well designed, Anyone want to comment on that one??

good stuff

ya simply need back presure on these torque engines. My buddy has same year bike with drags (02 wide glide)and while he is running the dog crap out a to shift at 6000 plus rpms to feel the rush I am still in the power and torque band and a gear lower and still pulling!
Car alarms? I did that on a stock 1200 sporty with slash cut slip ons(khromewerks as well as with a pair of cycle shacks before) but still could control them where needed. It is your money but CD has the facts and VYRb8R andHRK as well. If car alarms get you you going you could always keep em quiet and just kick the cars as you go buy. I'd get pissed if mine was set off!!...still kinda cool though!!!!!! Ever notice most of that stuff reads off road use only...I always feel I ought buy knobbies and go motor crossing? (I know they mean drag use... but does HD make a knobbie just in case though? )

I'd go find another dealer. Cycle Shack used to make SE slip on mufflers right up until the SEII started being made by V&H. The CS baffle is one of the best and their stuff flat works very well. Many bike rags have tested these and many others and the CS always ranks well. Your dealer is another one you can add to the full of B.S. list.

I suppose that he'll tell you that the SE stuff is better 'cause it is made by V&H and H-D demands higher quality?

V&H quality

I must've rcvd the 8 for fit and quality with the straight-shots I rcvd from you guys. I had to do extensive filing on the header pipes to allow the mufflers to slip on. V&H never took the ridges off after cutting. You're scaring me with the talk about the Thunderheaders. Wish V&H made pipes in black!
Really appreciate all your comments!!!!!