Custom aluminium air box 1st attempt

Dex94

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Dec 29, 2015
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Ok guys some of you may have got the wrong impression of me over past couple days I apologise for that. Anyway.. Here's pictures of my design not drew a lid up yet but will most likely just go with the flow when fabricating it. Hope you like the design any input or ideas before I make it would be great. I WILL NOT ARGUE! Lol
 
Here's a view from rear of air box I made the bottom like a cylinder shape and a sort of decline coming into the box from the top this maximises air flow inside the box not a great deal but every little helps!
 

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Here's the view of the right side if you were sitting on quad I put a small breather on side of box.. You can see slopes a lot better
 

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Here's a front view.. Hope you like it guys like I say any input would be appreciated. Be nice.. Lol
 

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I missed the pipe coming out front of box too... It's not a complete drawing. Just a 10min sketch. I will post finished product in first angle projection with dimensions of anyone wants to try making it
 
I don't know how much it will help since a filter will be going on it restricting flow but in school (graduating mechanical engineering this semester) they teach us to try and round the edge of the tube coming into the airbox slightly kinda like a velocity stack to get smoother air flow into the the connecting pipe.

Also I'm sure you already know, make sure you have as small of angles to the turns as you can in the connecting pipe. I think the connecting pipe is 10x more important to air flow as the actual air box because you can get a sh*t load of air in the tube but if the flow is nowhere near uniform flow then its useless and will not flow near its potential. And with those small angle turns make sure they have a large radius curve on the inside. You don't want big angles in there and you don't want the turns to be sharp either, you want it to be as smooth as you can get it.

Finally, I would suggest getting your turns and other restrictions close to the airbox side so that the end going into the carb is long and straight allowing to flow to get back to a uniform state of flow before it hits the carb. Also try to make your pipe close to the size of the carb so you don't have a huge reduction going into the carb causing turbulence.

All these things I stated are ideal for extremely high flow situations. They may not make a difference in something like the intake of a blaster but you never know. I thought I would try to quickly wrap up all that I know on air flow and you can chose to do what you want with that info.
 
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Nice information I agree with the curves on pipe ! Was planing this.hard fabricating something with all those radius etc if you get what I mean I will do my best though. It was never going to be a big project just something for a bit of fun. Having said that Good idea with moving intake ! Never crossed my mind I was planing on using some sort of racing duct used on a car? Would the tube fold in on its self whilst operating ie when throttle open I've heard of the original filters doing this. The design on the CFM is terrible with all those angles on pipe I never planned on doing that lol. I figured with the whole inside of the air box being rounded off it would most definitely help air flow instead on a box for example and it looks better? Lol Iam also graduating from college with mechanical engineering this year Iam stronger in different areas of mechanical you obviously know your stuff also good luck!
 
there used to be another brand of box, it used the stock 250r configuration in which the pipe came out of the box on an angle and gradually curved to the carb, eliminating the 45's of the CFM tube.
I'll see if I can find pics, I know there's some on here somewhere, I think lil speeddemon had one of these.
If I were to build a box, it would be that style


edit # 2.....

pics of custom made box in this thread, same 250r angles on the tube
http://www.blasterforum.com/threads/custom-alloy-air-box-ram-air-foam-filter.62919/


I found this thru google under SMS motorsports, which does not make blaster stuff anymore, I also think project Blaster used to sale a similar box, but they're gone too

it appears they're using the front half of the stock air tube on the one, others I've seen used a silicon reducer, and these are full width between the frame rails, wider than the CFM boxes to allow the filter to sit on that angle.


notice these are 2 different boxes, one tube enters the corner, the other the front face, but both were shown on the SMS website under the filters page.
http://www.snydermotorsports.net/productpages/airfilters.html
1234.jpg
2345.jpg
 
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there used to be another brand of box, it used the stock 250r configuration in which the pipe came out of the box on an angle and gradually curved to the carb, eliminating the 45's of the CFM tube.
I'll see if I can find pics, I know there's some on here somewhere, I think lil speeddemon had one of these.
If I were to build a box, it would be that style


edit: here ya go, I found this thru google under SMS motorsports, which does not make blaster stuff anymore, I also think project Blaster used to sale a similar box, but they're gone too

it appears they're using the front half of the stock air tube on the one, others I've seen used a silicon reducer, and these are full width between the frame rails, wider than the CFM boxes to allow the filter to sit on that angle.


notice these are 2 different boxes, one tube enters the corner, the other the front face, but both were shown on the SMS website under the filters page.
http://www.snydermotorsports.net/productpages/airfilters.html
View attachment 26407 View attachment 26408

That is some great info that I overlooked! You can reduce it down to one bend if it enters the airbox at an angle! That way you can also just do a simple straight pipe and bend it as little as possible to reach back to the airbox. That will reduce the number of bends and keep a smooth surface for air flow inside. I would do your best to keep the bend as close to the airbox as possible so that you can keep a long straight section before it enters the carb like I stated before.

I don't like the idea of using the part of the original boot that connects to the carb. My thoughts are that a centric reducer would have a lot better air flow because of less turbulence than the off-center stock boot.
 
I think this is a CFM airbox. Look at all the angles on that tube! DONT DO THAT!
CFM airbox.jpg



I think this is a SMS air box. That is better!
SMS airbox.jpg
 
<SOME SNIPPED>
I don't like the idea of using the part of the original boot that connects to the carb. My thoughts are that a centric reducer would have a lot better air flow because of less turbulence than the off-center stock boot.

My son and I felt the same way and tried making some alternate connectors. Nothing worked as good with the stock carb..

Dex, I didn't forget you. Stock box is 6.25" wide inside, 8.94" long inside, 8.75" deep at the back, 2.88 deep at the front.
The inlet panel is 7.75" long x 6" wide.
The frame rails are 6.75" wide inside and 9" wide outside.
The airbox is an integral part and much of the strength of the rear fenders and bodywork.

200081_10150156145940803_2202714_n.jpg

I'd tend to keep the stock box and just rework the carb ducting and filter.

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That is what I've got on mine. Nice straight shot of 50mm ducting to an aluminum adapter plate and huge filter.
The depth below the filter acts as a trap for all the muddy water that gets past my knees.

524637_10151389789205803_597375601_n.jpg

The seat has a foam gasket to seal the box. Air gets in at the front of the seat and around the gas tank.
Muddy water still gets in at times but so far none past the filter.
It's not just the filter that gets wet...
251506_10150264951440803_8168824_n.jpg


Sorry about all the mud on this thing.
Some guys like to stay home just polishing it...
... other go out to ride the heck out of it.

Steve
 
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I saw this one awk08 was thinking it was a pretty good design don't like the brackets tho that was my only fault with it doesn't look very professional lol. I like the silicone pipes too maybe call them try get one made up. I will go ahead with this design with a few tweeks you guys mentioned.. I only payed 15pounds for the aluminium sheet anyhow can buy more maybe make the both of them. Will definitely put the pipe where it is on the SMS. Also thanks Steve I got dimensions from a guy not sure if there correct will match the box size with the dimensions you have gave me thanks a lot! Will get some pics posted as soon as I start the project not had a chance been busy as heck just now !! Thanks again guys
 
i love this duct Steve going to use something like this that's awesome!
 
Like you did before, I quickly put my ideas and combined them with what you guys have said and made a real quick 3D model of it while I was here at work. I think this would be a great and simple design. You could put one of those outerwears on it for a lid and get a lot of air flow. I couldn't find a quick 30 degree angle to use so I just put in a 45 degree angle but I think a 30 would do better for air flow and filter mounting in the actual airbox. Tell me what you think. I think it's so good and simple I might have the welders here fab me up one

 
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Was going to get 1mm thick but let's be honest unless your doing aluminium tig welding every day it's a hard task hopfully the .2 will save me burning a huge hole in it lol I was thinking on rounding off the edges with a file that's been welded purely because it looks better like I say I can weld aluminium but only ever done alloy wheels and a few 5mm pipes. What's your thoughts guys keep the weld bead or file off so it's a nice round smooth edge that looks like it's been casted like that??