| Author | Message | ||
     M1combat |
Would it be worth while to seal the airbox (maybe with some O2 safe permatex or something), place a "uni" type foam filter in the intake tract that runs through the frame (just a hunk of that type of foam really, but making sure it couldn't be dislodged and sucked into the airbox), and then not use a filter in the stock location? This would greatly increase the size of the area inside the filter. Any thoughts? | ||
| Tank_bueller |
Seems like that would create an elevated vacuum inside the airbox, which also contains breather tubes. Might suck oil like crazy. Other provisions can be made for the tubes, which might make it a really sweet idea; but I thought the whole idea of removing the snorkel/cut airbox was to reduce airflow restrictions. I think the filter area would be inadequate to provide sufficient airflow through the relatively small hole in the frame. If enough air could be supplied, a setup like that may have advantages. I'm no scientist so I won't speculate on that(wait, this whole post is speculation!) just my half cent tank | ||
| M1combat |
I was thinking about the cross section of the intake as well (especially with it being filtered). I was thinking I could find a very free flowing filter for that. Of course, it wouldn't filter as well, but as long as it caught the big stuff I'd be happy. I'm not running the Baja  . WRT the suction and puking oil from the tubes... In my case I'm running a Norris Performance catch can and my tubes have long been removed from the airbox. BTW... Those tubes are inside the filtered are in stock configuration. I was actually thinking it would create less vacuum though, as long as a filter with suitable flow could be found. | ||
| Ronlv |
this should go in kv under engine intake thanks in advance for moveing it there oh yah did you do a search first?? (Message edited by ronlv on September 29, 2005) | ||
| Buelltroll |
haha | ||
| M1combat |
Yeah... I did. If I do it and it becomes knowledge as opposed to wild speculation... I'll write something up in the knowledge vault (unless of course an admin would like it moved there... then it'll get there much sooner). Didn't quite seem like knowledge vault material to me at the time. | ||
| Tank_bueller |
Assuming airflow is good, and you already have the "tubes done", it should make for some killer throttle response. (more wild speculation) In stock config., the area between the throttle body and the filter is pretty small, which means the vacuum would grow in that area very fast. With the new setup, the massively increased volume between the filter and the T/B would take longer to make the same vacuum, resulting in a bigger initial gulp of air. I think the ECU should handle this fine, and as a bonus, it may smooth out the torque curve by having a bigger volume to dissipate the intake pulses. The "cone" may need some raising/lowering to optimize the different flow pattern(I would bet on it needing more room). I think I saw a pic of a race bike with intake tubing out of the top of the airbox to the fairing. I bet they know more about this than me. (wild speculation: off) (p.s. maybe Blake could hook us up with a "Wild Speculation" section for us crazy folk ) | ||
| Reepicheep |
I think if you measure the gap in the airbox, calculate the area as it goes around the entire circumference, and come up with the total intake area, you will find that it is at least as large as the snorkel tube, maybe larger. | ||
| Buellin_ri |
wouldn't you get more airflow with a drilled/modifed airbox? You get all that area plus the snorkle tube vs just the snorkle tube. Also wouldn't the air intake be hotter coming from the snorkle (heat from the motor and frame) vs open box? Good one ron.  (Message edited by buellin_Ri on September 29, 2005) | ||
| Blake |
Thanks Ron. You are right on target and we sure do appreciate your help in reminding folks to post tech issues to the appropriate KV topic. 172689 | ||
| Johnb |
m1 - redesign the airbox  why does it have to look like a traditional gas tank anyway? found that xb intake scoops pic Tank_bueller was talkin about.  | ||
| M1combat |
I already have a severely chopped airbox. All that's left of it is the area covering the filter. It works well. What I'm going for is more volume between the throttle body and the filter. Sorry for the mis-placed post Blake. | ||
| No_rice |
ok..... i needed to eliminate the filter some how because it was in the way on my xb9. took it out, chopped the snorkel. went to the hardware store and picked up the finest window screen i could find (not the metal kind obviously). laid it over the intake hole, and popped the little bit of the snorkel that was left back in to its place. then trimmed the excess around the snorkel off. been running it that way since last year and runs great. did think about trying to find a really thin something to sandwich in between another chunk of screen to filter a little more though | ||
| Djkaplan |
"What I'm going for is more volume between the throttle body and the filter." Increasing plenum volume provides a damping effect for pressure variations in the airbox during the intake stroke. It's a good thing, especially for an engine that takes big gulps of air at a time. | ||
| Blake |
Great and interesting and informative tech topic. I love this kind of stuff. Please post all future threads like this in the applicable Knowledge Vault topic. We'll be moving this one there soon. Thanks, Blake 172689 | ||
| Ronlv |
how do you remove you cluster and rewire to run without it? like on the hals bike with the force induction. | ||
| M1combat |
That's about what I was thinking No-Rice... I just want to be reasonably certain that I won't get any sand in the box. That's why I wanted to use a sealant between the upper and lower inner airbox pieces. A very fine screen would probably be enough. What about running two layers of this screen? One at the top and one at the bottom of the hole in the frame and then putting 1"x1"x1" cubes of a decent foam in there? Maybe 12 cubes. I'm imagining that they would get blown around in there like the ping pong balls in some state lottery machines... If you get my drift. If they were slightly oiled like you would with a regular filter then they would probably work pretty well to collect a lot of the particles that DO make it through the screen, but hardly affecting the airflow at all. | ||
| Perry |
I am going to speculate that it won't be a great setup. My reasoning is that the air intake tube is already the bottleneck (that's why snorkel removal improves power and response.) Adding any filter, no matter how free-flowing is going to reduce air flow at least a little, and it will do so at exactly the spot that is already a bottleneck. True, the damping effect of a larger volume of air between the filter and intake is a good thing, but I believe by constricting the flow at the frame intake/snorkel position you will create a near constant vacuum in there because you just won't flow enough air. Your proposal will produce exactly the same results (performance wise) as would removing the filter completely and partially blocking the air intake. Blocking the intake partially would mimic the effects of a filter. However, practically speaking, the amount of surface area of the K&N filter is so VASTLY greater than the surface area of the air intake. You'd be hard pressed to find a filter material that flows freely enough (and still works) to be able to fit in the small frame opening and still offer as much flow as the large surface of the K&N. And finally, because your proposal has so much lower surface area for the filter, you would undoubtedly have your filter get dirty/clogged MUCH faster. | ||
| No_rice |
well i was kind of concerned about dust and things getting in the air box, but have u ever looked around at the amount of harleys running velocity stacks with just a screen in them. i have plenty of friends that have them on theirs and have lots of miles that way with no apparent side effects as of yet. i figured id give it a try. hey if all else fails it gives me an excuse to bore it out and build it more, lol. i have put 9000 miles on it that way though and is still running strong | ||
| Diablobrian |
for those guys running cruisers a little loss of horsepower because of blow-by/scored cylinders isn't necessarily that big of a deal. Performance is not at the top of the wish list, STYLE is. If you are trying to get better performance I would look other places for ideas. IMHO | ||
| M1combat |
You have a point there Brian... If I do come up with a miracle filter material that allows it though, I'll let you all know. I'm not really willing to run it w/o a filter. Maybe a K&N Pod filter in the frame? I know there will be power gains with a much larger intake plenum, I just want to make sure I have a filter  . | ||
| Kowpow225 |
This is just a suggestion. Maybe instead of trying to fit a filter 'inside' of the old snorkel location up in the frame, perhaps you could devise a way to mount a much bigger filter in the rear cylinder scoop so that it wouldn't be an eyesore. Plus with this added room, a much larger filter could be used. This would obviously take away from the much needed cooling ability that scoop already gives, so a right side scoop may be in order for this setup. If I remember, there is a small 'lip' on the bottom of the frame where the snorkel used to protrude, so this could be a good anchoring point for a new filter. Some sort of large rubberish tube would be needed to connect filter to frame and of course some sensor safe silicon to complete the seal. If you would be willing to take that left side scoop off altogether, an even BIGGER filter, nearly the same size as stock could be used. A forcewinder like the tubeframers can use is what I have in mind connected to the hole in the frame. The only thing slowing this idea down is that the opening is sort of triangular and not round. It would be hard to get a piece to 'fit' this. I love these topics.... | ||
| M1combat |
I'm certainly not willing to sacrifice cooling for more power . I'd consider the right side scoop, but I have a Force header so that's pretty much out of the question . I'm thinking a cone shaped filter inside the frame pass-thru would work though. I have one that's not a K&N so I could check fitment at some point. I'd get a K&N with the filtered top if I decide to try it out. I'm going to look around for filters... |
