| Author | Message | ||
     Mikep |
Reference: The Bad Weather Bikers' BBS » XBoard » Archives 0306 (thru June 2003) » XB exhaust systems/mufflers » Archive through June 04, 2003 Here is a photo of a method to open up your airbox and still retain the stock Velocity Stack height. I eye-balled the supporting webs to run up from each of the clip locations. mike  | ||
| Darthane |
Mike, none of the modifications that we've discussed on the board actually REQUIRE a velocity stack modification. It was just something Joey (Ar15ls or somesuch...I haven't seen him post in a while...) and I did based on our logic of the situation. It's my understanding that the Force air filter that comes with their system for the XB is actually taller than the stock or K&N, which would have alleviated the 'problem' (it's not one, just lack of a better term) as Joey and I saw it. | ||
| Ar15ls1 |
Hey Darthane , whats up! I havent posted in a while because I have been playing with my other hobby. I do check in once in a while. Thats a pretty good looking airbox. It was cut pretty symmetric. I still am happy with our setup. Its a little noisy but I believe it is a all around better piece for making power. Also I still stand by the cut down velocity stack. | ||
| Gonen60 |
Why cut up the air box like that? The Air enters the Left side intake scoop, goes into the Air box and into the filter. How does cutting up the inner-air box Help? I could see adding some sort of tube, that connects to the end of the air intake plumbing, and bends right into the side of the filter, that way, forcing all incoming air directly into the filter... | ||
| Darthane |
Gonen60, Cutting the upper air box like that allows air to flow into the filter from all around the outer air box cover (blue, white, black, whatever color...the surlyn one) rather than just through the air inlet through the frame. Brian from Tilley's posted a 4hp and 6ft/lbs gain just by 'holing' his airbox similar to what Skully did (you can find pictures of his in the Tales section under "From Cruiser to Sport Bike" )Joey and I took it a step further and removed the upper air box completely and creating a plate to seal the top of the filter, then cutting down the velocity stack to allow easier airflow into the throttle body. If you look at a stock air box's filter after a while, you will see that only the left front quarter of it is dirty, indicating that the vast majority of air flow through the filter is only from that area. Mine, since doing my mod, is much more 'evenly' dirty, indicating that it is now pulling air through the entire filter rather than just that one quarter. Obviously this is an improvement. Joey, what's your 'other' hobby? Nice to see you're still around. I'm getting ready for the 15K maintenance on my Firebolt (replacing belt and idler pully this time around...), where are you sitting? Bryan edited by darthane on September 05, 2003 | ||
| Gonen60 |
Bryan..Sorry if this is a dumb question but here goes. The picture posted up above, That is the inner-air box, correct ? and then our colored one attaches over top of that, creating an enclosure over the inner box. Air enters the side intake, flows up into the inner box, and into the filter. cutting the inner box allows the air to then flow around, escaping the inner box, and bounce around the walls of the outer colored air box. I don't see where it matters if it is closed off by the inner or outer air box walls... Is air getting in, somewhere other than the side intake? hope you understand what i am saying...LOL | ||
| Mikep |
1. Cut up the airbox to increase airflow and therefore horsepower. 2. Use the original airbox in order to retain the bump above the velocity stack (velocity stacks are typically tuned lengths to provide best power). Changing the original length changes the tuning. 3. Genon60 - The tube idea is what Buell did with the original. The stock setup forces air to the filter. 4. Does opening up the area around the filter increase h.p.? I really do not know, I'd have to get to a dyno and test with original cover and with the skeletal cover. 5. The skeletal cover does not require any velocity stack mods, nor does it require drilling into your baseplate and using two standoffs, bolts, nuts, etc. It does not compromise sealing at the front and rear of the filter either. 6. Mine is noisy too. mikeyp | ||
| Ar15ls1 |
Bryan, you have 15000 miles on your bike already. I have about 3500 miles on mine. Its been raining a lot here in Louisiana. When you ride its a hit and miss thing. We have scattered showers for about 5 months. This is just one of my excuses. I have other reasons why I havent been riding as much. My other hobby is cars. I have had a 98 firebird ls1 that ran high 11's ,a 2001 ss camaro that ran 12.30's a 97 supercharged dodge dakota that ran high 13's and now I am playing with a 2003 dodge srt4. I am shooting for high 12's with this turbocharged four cylinder. As soon as I accomplish this , I will be getting back into the firebolt and see if I can get it to run like those new xb12's. } | ||
| Glitch |
Gone: The air box cover is not air tight. Therefore all those hole do help air flow. | ||
| Gonen60 |
Does air get into the inner air box by any other means, other than the side intake scoop??? I thought it was basically a low-tech RAM-AIR system....Gather air from a large opening (side air intake) funnel through directly into the air box, forcing the air onto a specific spot (air filter) where am I going wrong? | ||
| Gonen60 |
Gone: The air box cover is not air tight. Therefore all those hole do help air flow }Ok, but the inner air box is air tight, at least it appears to be, I am looking at my 03 parts catalog. the inner box as a seal gasket. I would think, grabbing the air from the side intake, forcing it into the sealed airbox, it would flow then, right into the filter. | ||
| Mikep |
Brian from Tilley's posted a 4hp and 6ft/lbs gain just by 'holing' his airbox Even though the stock airbox is like 'Ram Air', it looks like 'holing' the inner airbox provides a power increase. mikeyp | ||
| Mikep |
Brian from Tilley's posted a 4hp and 6ft/lbs gain just by 'holing' his airbox Hey Brian from Tilley's! Is that the only thing you did to fine the 4hp and 6ft lbs? What else was done to the bike before the 'holed' airbox dyno run? mikeyp | ||
| Captainplanet |
If you look at the stock setup, the scoop really feeds most of the air on to the cyliders. It does not just feed the airbox. Run a hair dryer though the scoop and hold your hand near the cylinder and you will see what is happening. | ||
| Darthane |
All right. First of all, like the Captain said, it is NOT a true Ram Air system. It's just a scoop, most of the airflow is directed over the rear cylinder. If the scoop was closed on the back end, then it would be a ram air system. Second, the reason it provides a performance increase is that the airbox cover, the surlyn one, is not sealed against the frame. When you open the airbox like above, it draws air from around the edges of the airbox cover in addition to the original hole. Third, the length of the velocity stack doesn't make a difference to the airspeed going through it - only the beginning and end diameters of the tube. The reason Joey and I altered ours was that the stock velocity stack's upper rim is only like 1/2" from the top of the filter. This means that all that air has to run through the filter, then up and around the lip before heading down the stack. By lowering it, yet keeping the diameters as mentioned the same, we allowed a simpler path for the airflow through the filter and into the throttle body. As far as the difference between the way Joey and I did it and the way Mikep did it, there isn't one except how deeply involved in the process you're willing to get. I seriously doubt the air flow between his and our is even enough to register on any scale you could use. If you do this, as noted, your valvetrain noise volume will increase tenfold. The bike overall is louder, I've had several of my Bueller friends comment on it, the change was a noticable increase. Joey, those little SRT/4s look like shitloads of fun. I'm seriously considering one as a 'toy' car a few years from now. I'd kill to have one of the SRT/10 Rams...Ram with Viper engine...-=drools=-} | ||
| Dynarider |
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| Bud |
Anyone tried a xb12 airbox cover on a 9 ??? What I have read and heard, ( trojan & a buell guy in hamburg  ) the design is a big improvement over the stock 9er lid, And where the 9 pick’s up a few horses when cutting/ removing the cover, The 12 loses a few ? just me wondering, gr,Bud edited by bud on September 05, 2003 | ||
| Buckinfubba |
The only other thing is the race kit. But we have found that big holes in the air box have left flat sports thru the power band. I used a 3/8th drill bit and put as many holes as possible , then I venturied every hole. gone more air more power... the I dea with the 12 air box cover is an improvement still waiting to play with it. Plus heres another Idea I haven't had time to do. Go to home depot or lowes or wherever and get some weather stripping and seal the outer airbox cover to the frame. I think this would turn it into a pressurized airbox. When I get done developing this pipe and have some time I will dyno this I dea and see how it works. But somebody who has some time this weekend should try it and see if it makes any difference on the ass dyno....just my poor feeble mind working to hard, Brian Tilley hd/buell 704-872-3883 buckinfubba@hotmail.com | ||
| Gonen60 |
I did notice when air goes into the side air intake, a lot of air bleads off onto the engine. So I would think the best solution would be to connect some kind of tube or duct system, that runs from the side air intake directly into the air box... as far as the new American Sport Bike carbon air box with the side opening, two things come to mind. The openings are not getting clean air (fairing blocks it) and If you happened to get caught in the rain, water would go directly onto your air filter..Like the photo above, on the red bike, the air intake on top of the air box, is not getting clean air, it looks to be behind the fairing.... and you can't really dyno for the full effect of ram air..I read where some guys try setting up fans or blowers, but you couldn't ever get true reading that way... | ||
| Gonen60 |
Plus heres another Idea I haven't had time to do. Go to home depot or lowes or wherever and get some weather stripping and seal the outer airbox cover to the frame. but if you did this, you would no longer pick up that extra air from the edges of the outer air box...you would be back at square one, relying on air that only flows in from the side scoop. I think this would turn it into a pressurized airbox isn't the inner air box already pressurized? | ||
| Dblhaulxb9s |
Hey Guys, Its Morgan. I did the Plexiglass version but did not cut the Velocity Stack down. I do not have any other performance mods (ie no after market exhaust) and I have noticed a little more power (ass dyno results). I don't think it really slows the air down much having the plexi-glass that close. I might try doing the "skully" method to the original and trading out back and forth for a day to see if there is any difference. I am going to get the D&D muffler this winter but until then has anyone heard what happens when you just hack the ass end of the stock muffler off and turn it into a straight pipe. I know that Big sherm had a straight pipe built but I was wondering if I would loose all of my low end power. Wow that might be the longest message I have ever posted. By the way. I am loving my Crossroads bars. Way more control and way cooler looking. I will post pics as soon as I get a new camera (just ordered one). Morgan | ||
| Gonen60 |
two more thoughts.. why not just remove the whole inner air box cover, and seal just over top of filter... or run 2 air gathering tubes from the front, into to air box like this buell race bike..  | ||
| Glitch |
isn't the inner air box already pressurized? In a word ... no. | ||
| Gonen60 |
isn't the inner air box already pressurized? Ok, not pressurized, but sealed. and only getting air funneled into it, from the side air scoop.. So Just run a hose from the air scoop up through the opening and into the sealed airbox..The side air scoop is in a great spot grabbing clean air, but like pointed out, a lot of the air bleeds off onto the engine. Adding a hose from the mouth of the side scoop, snaking up through the opening, would ram a lot more air into the sealed enclosure (inner air box)} | ||
| Ar15ls1 |
One thing to remember is that I dynod my bike with the velocity stack on and off back to back. I gain 2 hp with the stack completely off. I also lost 1 lb ft of torque. I figured with an open air box and with the bike moving this gain would be even more. This is what made me decide to cut my stack shorter. And just by looking at it and the way it only has a small area to suck any air in, common sense should tell you that cutting the velocity stack down will allow more air to be sucked in. It is an easier path for the air to flow through. Yes Bryan, I really like this little srt 4 banger alot. It is fun as hell beating up on late model lt1's and mustangs. They never know what hit them. | ||
| Captainplanet |
Morgan, I modified a stock pipe for my bike. I put up a pic a while back. I really can't tell much at all in performance difference, but the bike sounds great and runs fine. | ||
| Glitch |
Remember ram air is only going to help you when you are going way fast and then only a little bit. We were at Road Atlanta once and saw one of the Kawasaki teams had taped off one of the ram air intakes. When I asked why they said it was because they were losing hp when they needed it (on that track). More air is good, and I'm not saying ram air is bad, just that you have to be going really really fast for a ram air intake to pressurize the airbox. The funnel you make for a street bike would have to be larger then you'd probably like to do any real good. Air like most things in nature will always take the path of least resistance, in other words around the ram intake, that's why they have to be big, and you have to be going fast. | ||
| Darthane |
why not just remove the whole inner air box cover, and seal just over top of filter... <~~Gonen60 This is precisely what Joey, Morgan, and I have done. It's the home-brew version of the Force Air Intake for the XBs. Why spend $300 when you can spend $20? | ||
| Gonen60 |
Darthane..got any photo's ? | ||
| Henrik |
Interesting discussion; two side comments regarding this. 1) SV racers cut the top out of the stock SV airfilter - until it was realized that it caused trouble making the power curve quite jagged - impossible to smooth out. 2) length of the intake tract affects flow dynamics in the intake tract, cylinder fill and such - it's possible the changing the snorkle length will too. Just something to think about. Henrik |
