airbox?

[ml450r]

I see alot of guys running intakes with open filters, no airbox. What about water and mud......

I don't ride in water or mud, but when I had my hybrid, I was at Loretta's and it rained. Of course the race went on. I had an open filter, I sucked mud and water into the filter, ruined the whole top end, dnf'd.

I am just wondering if this happens to everyone that runs no airbox, or if it just did it to me for some reason?

[TNT]

Been contemplating this one too, some cut it out but modify it somehow so they can put it back on in mud easily. I’m also concerned about the AAPTS in the air-box, you’d think it get dirty and effect the EFI although this sensor from what I understand is basically an on board barometer that compensates for ambient air changes and altitude and fine tunes the ECU air mass caculation. LTR311 who does dyno runs often said he sees good gains on just about every quad he removes the box on. I can believe this on the dyno, reason is the more air mass you can get to that filter the better, at the end of the intake track that added volume of air will help fuel atomization develop faster meaning more torque, on the dirt track however not sure if it’s dirty clogging the filter. To know for sure one test one could run is fan a bunch of dirt at the filter and AAPTS and see if there is a power loss, you know at some point there will be how much and how fast is the question. I can see more maintenance, may be a MX 10 min moto thing not for XC.

We hope to see BCS at a national soon so I can see exactly how this works. Main reason I want it out is our K&N/FCI is huge and we never finished the FCI design to not have to remove it to clean the filter, removing the box would solve. I like the BIG FCI it's just to big for the box lol!

http://i280.photobucket.com/albums/kk191/Terrylport/FCI1.jpg
http://i280.photobucket.com/albums/kk191/Terrylport/FCI2.jpg

I cut some holes in our YAM's box in the rear not sure what it did actually. :confused:

[bomberman]

if ur running a can am with no motorwork, you get more hp out of it with the airbox lid on.

[LTRracer4]

I have an open air box, and just two days ago I was riding a track with puddles scattered around, when I was done riding that day I notice splashed mud and water on the filter. It raised alarm, so I'm curious about this too

[ml450r]

Chris, did you look in the intake tube, anything in there?



bomber --it is a race engine, but I dynod my stock09 mx. It actually did best with airbox lid off and got extra 1 hp at about 7000 with seat off too

[Mr. Big Time]

drill some 1" holes in the side opposite of exhaust. that will allow more air therefore creating more hp, yet allowing protection from the mud. Or cut the airbox in a way you can put it back on if you have to

[Legacy109]

I am running a no air box setup on mine, my brother has run this setup all summer long last year without problems, even in mud conditions. But wioth the air box removed you should use an outerwear

[LTMFB]

legacy, post some detailed pics if you could..

[ScottB125]

Mine picked up power too with the lid off/seat off. The motor wants more air. I run with my lid off and have drill 3 1" holes in the rear of the box. I haven't had any issues.

[TNT]

I think the answer to OP is noone really knows....We've heard there are "no issue" but technically we have no tested proof on this quad of a hp gain or loss. Further, some quads will be different than others, some have different flow rates than others. The combustion can is only so large and who really knows if increased volume at the filter means increase velocity at the port. That my friends I am sure entirely depends on the your specific intake configuration. Just remember air is 13- 14 xs more important to performance than fuel.

Even when it comes to porting heads on flow benches some paying $500 as a sub assemblies to an air track installation, what looks good on the bench may not on the track noone knows how it interacts with the rest of the track....So we put it on a dyno and see some gains, then theres more to it than that w/EFI, now we have all the sensors like MAP(flow rate), AAPTS(air tunning), telling an ECU to change AFR that can add or subtract from power, or should I say rethink theoriticals that we seen on the dyno and bench to other actual inputs and outputs on the track. I believe AAPTS is a barometer so if it gets dirty it affects AFR.

So to really know you'd need to simulate a test of muddy and dusty conditions run the quad on the track then measure hp some how, or simulate the conditions on the dyno. In either case, the end measurable result has to be AFR atomization and hp gains/losses in muddy/dusty conditions the dyno does not account for.

Now there is a very complicated answer to a simply question, what I do best lol, but to me it's all about fact not hersay or clean air dyno results, or what everyone else is doing(carb motors included) even the pro-race teams(they change thier minds so often not sure they really know!..or just keeping trying stuff they can sell or not based on fact or what some think works for everyone that follow thier blind leading the blind lead theories)....hahahha!

So I'll run some test on the track and see for myself on my quad my design(as u can see mine as yours are unique), if you've done this and really feel little gains box off and/or holes in box, your good to go, but that is not a generality for everyone unless you got the same mods. I can't imagine there are huge gains...Just take the air box off see how fast your filter gets dirty on the track and conditions YOU run at the end of your moto when you may need 1 or 2 hps to win a race, then see if we feel hp gains, then ask the question is it really worth a dirty filter and AAPTS wear and tear...:confused:

The more I look at our protoype FCI the more I like it the biggest beast out there, and I don't think it's what needs change but rather the box! I'll look at modifing maybe cutting some of the side walls out leave the bottom to protect the fillter/AAPTS.

TNT :D

[TNT]

Well ML I see you put your Can in 2nd at Pell City last weekend in Vet A 30 + and picked up a little contingency $, nice! ...was that with or without the air-box? :huh :D

[ml450r]

Had the airbox, was expecting a mud race.

[allbones512]

Im running a bigger intake from BCS and a K&N air filter and had no problems racing in the mud.