There have been several here who have gone the route of gutting the cat from '08-up header and using slip-ons,.. as opposed to a full system from one manufacturer. I read one comparision of Brocks CT duals to a Muzzy single, and the gerneral concensous was while the Brock made singe digit improvements over Muzzy, the difference is close to negligiable on the street This leaves me to believe the secret is in the tune, and wonder, how the gutted header and slip-ons compare to a full system, each with a proper tune? Bean, for expample, reports excellent improvements with the gutted header/slip-om combination running Jeffos tune. Would like to see some dyno numbers..

One priority for me on my 2010 is maitaining the strong bottom-end pull this bike has. Great responsiveness at 3-4000, where I spend most if the time.

i know that I can do very well with a full Brocks CD Duals system and his tuning, but my budget begs for considering some of the alternatives. I do want to wake this bike up across the graph, and get the best-bang for buck in doing so.

Do we have some dyno and real world numbers on the gutted stock header and sip-ons, using tuners such as Jeffo, Brocks, etc?

The CAN Con:
1. Smash the cat out, you lose a slight bit of grunt. Yes, it is a slower-downer, but I left the cat in the bag.
2. Why cut the stocker up. This is your best gruntune are the stock pipes. Do not tamper with!
3. That price balance.
4. Oh, I gutted [1] stock can. If I really tore up some rpm, that one bolt holding on in the back, would move the cap out that wasn't secured well. WOT a pain that was taking a rubber mallet to it to send it back home. I was going to somehow quiet it down inside later sometime. Why rivet it back closed was the idea.
5. I installed a bearing over the back exhaust hole to quiet it down, being the outside idea. Plus, I used an early model header without a cat. My idea was to run a sleeper 4-in-1. During the low grunt applications [that were slightly lost somewhat] due to the one pipe mod, like you, I still wanted both worlds. No longer could she jump, say.
6. On went the proverbial 'muffler bearing' to quiet the home front are the neighbors getting on my case. No, they didn't. But that noise got to me. The grunt got to me too.
7. Returning back to stock, what grunt I remember was all over the place, but you did feel that lag come in, meaning, not as free flowing. Because you want that air release to happen.
8. And again, the compromise is back in the game with the photos above. Took me a half hour of pain I'm paying for working on this cheap throw away for a miserable tune up.
9. This thing sounds corny now. I set my hand in the back of both pipes and it's WOW! WOT a pulse coming out of that thing. Niiiiice.
10. Other than the obnoxious noise, It may also give the 02 a wrong read sort of. Thus the eyesore at the AFR begins.

The PRO Side:
A. The hand balancing act of the price of parts is parts. A full exhaust being the 4-in-1, will lighten the bike. Will lose the grunt. Will open the top end gain. You eat both that price and the grunt. You can't have it both ways, take the pill and swallow it. HP gained. Grunt so-so.
B. The cat gut call. Either side wins. I see no difference in that slight move if closed course is all about speed and HP. But the pro side sort of looks at the fatter header to compensate for a screen that is on the back of the air cleaner sort of flow. Not much, but a change in flow none the less. Remember, this is the pro side and you sit home on the couch now. This is for all the guts [out], all the marbles of torque are for the birds.
C. The dual set. The price balance and I have 3 different combos to choose from. DO I?? Buy the duals, gut the cat combo? That is one way to apply speed out the back.
D. Do I run a cheater dually? Gut the dual I just bought new and keep running a cheater beater noise machine?> One more option on the pro side.
E. Dual gut job I keep pro siding on the insiding. Your second option on the chopping block.
F. ING A, look at that cheap asshit design. They should cut up the other brands, see what is going on. The internals of this pile needs some work. No V-stacking. A decent idea out, but to match the guts of the 14? NFW hose say!
G. The pro side is that if you do not like all that extra modding on the aftermarket side, the pro side says there is a grunt side waiting in a box... The OEM = Untampered with. The extra grunt waiting in the wings was that take off to put on less grunt.
H. Is for, Homey does not use no stunk'inn fuel cutter on a muffler'd pipe. That is the beauty of open loop.

I have access to another 2010 header, so I'd leave the original header and cans in tact in the case I wasn't pleased/satisfied w/the mod.

Was thinking about using D&D slip-ons w/the gutted header. (My other motivation here is to lose the heat from those cats. I live in TX and the summer has been brutal) Losing the weight of those OEM mufflers can't be bad, either.

In the end, it looks like a full system makes more sense. The D&D's are more than $500, and I'd have a couple hundred in a gutted OEM replacement header. I should know better; seldom have saved anything by saving a few bucks up front.

I realize that there will be some compromise in gaining the power I'm looking for, and the tune seems to be the key. Lots of threads here on the topic, been reading for days. Many seem most concerned with max top end power; I get that, but I'm willing to sacrifice single-digit top end power to have a flatter gain across the graph, and retain as much of the low-end grunt as I can. May be asking for too much, but still interested in exploring that goal.

Thanks for your reply.

I too have been debating the same thing. I think (when I get back and can finally work on my baby) that Im going to sell the slip ons go with a full system, for 1) the weight loss and 2) the overall extra HP. Then adjust my gearing to get back the low end grunt. Seems like the best of both worlds, no?

Yep, that would best the both worlds is a pipe and gear, soldier. Brings you up to a spin-up, but how fast? You'll be looking for 7th and 8th gear when cruising. If this is a round town, short tour, no sleepover, then yeah, you could live with that world.

My road test today was to park myself in front of a gaggle of cars. I split the lane to get up front for a clean, no cars ahead kind of jump to safety. Sombitch, that bike carried the front wheel half way thru the intersection and that cut pipe was for that effect I was looking for.

Pulled the grunt out of one pipe, but kept the other one sort of pulsed for wheel popping. Once the fuel cutter came on, the smooooooooth kicked in, I was laughing in my helmet on the wheel carry and then I was sitting on that bike noticing the fuel changing that bike smoother, stronger... In my head I was...

* Last updated by: Hub on 8/20/2011 @ 6:42 PM *

Soldier, seems there's more than one way to pluck a buzzard. I keep reading here, and accumulating info on other's experiences. At some point or another, we'll have to make our best judgement and go for it. I'm hoping to benefit by others mistakes as well as successes. Check the thread 'midpipe cat'. Bean (nice aussie)had really good results from a gutted header and aftermarket slip-ons, with Jeffo's tune. But again, looks like an aftermarket pipe is nearly as cost effective; perhaps more so in added performance/weight reduction.

Some here like the effect of gearing changes, but many drag race their bikes. I've seen quite a few (Blue07 would be one) with a collection of sprockets, only to say they found that, afterall, the stock gearing was best for their purposes. Mine is new, bone stock, and power-wheelies 1st gear to the point it's caught me by surprize a couple of times. As soon as it comes on the cam, up she goes. Shorter gearing would surely make that more interesting...

I think my best bet is to not get into too much of a hurry, and put my pennies back for the best pipe available. What I'm studying on now, is the whole tuning question. Most of what's been available are "piggyback" units, that fool the ECM. That is such old tech, when compared to what we've been doing with modern cars for the last 15 years or more. Been able to flash GM and Ford ECM's for a long time. Someone has finally cracked the Kaw codes, and once that Pandora's box has been opened, we'll see that ability blossom. The tuners will have so much more control of each parimeter. Seems worth waiting for.

Best of luck with your ride, keep us posted on which way you go and the results.

Well, I've learned from a member here that very little of the ECU code has been cracked, and more progress in that direction is unlikely. Seems the most popular piggyback tunes here are Brocks and Jeffos, and likely as good as that will get. I want a harder hit from this thing without getting in the motor, so I'll go with what's been proven to give good results.

prog,

You may get the same hit, but it may be smoother, a bit more stout. The hit you might want is more a twitch. But some rather not go that route. That is running the one throttle plate, the hack to the gps sensor. But, here you run into that throttle response that feels snappy but it limps your bike.

If you want that hit, turn the key and never look back, it is down to a pipe [not gutted] and map; no other mods. Flies run better in the later models like yours. The gps hit is a lagger in the overall performance, so you eliminate those two mods along with the OEMod to the pipe. With the stockers hanging, you can select if you wanted that hit or the stock pipes did it for you on the lower end grunt side.

Besides, those stock pipes are heavy even gutted w/header. And if you want that hit, the lighter the better.

The end to this story, for me, is a new Muzzy M-14 on the way.