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Discussion Starter #1
Have any of you taken out the baffle in your airbox and drilled holes in the lid? I am thinking about doing it rather than getting a powerbreather, plus it will still look stock. ;) I would think that you wouldn't even need to jet up with it since they are fat from the factory and the only thing that may need done is a fatter pilot jet to compensate a low end lean bog....
Any thoughts?
 

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Well, i wouldn't do anything until your warrenty is up. Anyhow why would you want to draw that hot underhood air into them carbs. Cold air = power :D

Auggie
 

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Discussion Starter #3
I already talked with my dealer/mechs. to find out what all I can get away with as far as warranty goes, and he said he had my back so not to worried about that. I would also only drill the holes where the vents are blowing the cold air in. There are two places on the lid that have cold air directly blowing in, and would almost be like a ram air setup....
There has to be someone on here thats tried something like this before. ???
 

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Discussion Starter #4
Originally posted by Auggie@Nov 3 2002, 10:49 PM
Anyhow why would you want to draw that hot underhood air into them carbs. Cold air = power  :D

   Auggie
If anything the powerbreather would be worse as far as drawing in hot air because the whole lid is practicly open. They way I am thinking of doing it, it would only be open where air is forced down and would have thin foam covering the holes so no just was sucked into the carbs.
It sounds like a good idea to me, but am I missing something here? I would think as long as your jetting is on, you would have nothing to worry about.
 

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Phazerhater your idea seems sound to me. You should look in snowtech though. They had a new device that was designed for what your talking about. It had these adjustable inlets that you would install in the wholes that you drill. Something worth checking out.
 

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on my 99 zrt 800 i had 5 holes drilled across the front of the airbox when i bought it, it had foam arcoss the holes, when i bought it i b acked this up with with some wire mesh.
 

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Many either drill holes or cut a slot 2-3" tall the width of both carbs in the front of the air box. The thought is that the increased underhood pressure will force air into the box. Use a filter material and screens.
:)
Sled..
 

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Discussion Starter #8
I'm wanting to drill the holes under the lid though, where your tools go so that the top lid with the jetting chart covers it and it still looks stock. I know I won't get quit as good of air flow that way as opposed to drilling in front of the box, but the top lid is raised up about an inch and has open slots all the way around. I am thinking of going with a 2"-3" hole towards the front of the box on the left and right hand side and then maybe put a could 1" holes towards the back of the box. There is an open vent that is just behing the windshield that blows directly in toward the back of the box.
I just don't want to go slapping too many holes in there though!haha Would I be better off with just the two bigger holes, or go with a couple of each? I will probably give this a try tonight. The only thing that I can see needing to be adjusted is the pilot jet....
 

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Well, before you do anything you should read these two articles on the SW Tech Bench.
1) Airbox Temperatures
2) Pipe Temp and Airbox Pumping

Auggie ???
 

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Discussion Starter #11
Thanks Auggie. I read those along with several others on the subject. It seems everyone has a different opinion on the subject. I read some articles that said this should be the first "mod" done to your sled, and then others that say leave it and to not even run a powerbreather. After reading every article I could find on the subject, I went ahead and gutted her last night. I took out the baffles and wall inside and put in two 3" holes on the top of the box. I have some close woven mesh with foam over top of that to cover the holes. I then made a sliding cover so I can slide a piece of plastic over the holes and cover it on those subzero days.
I started it up and was suprised that it didn't seem any louder that before. After it warmed up I rapped the throttle a couple times and as I suspected there was a bog on the low end. I moved the needle up one clip and that took care of the problem. I left stock mains in also and will just watch piston wash very carefuly the first few trips out. After I get it broke in I am going to install the VF3 reeds I got for it and will jet up one size with that and watch wash again and jet from there.
I can't say if there is better throttle response or any more hp since it has the 100:1 mixture in and only has 0.6 miles on a stand, but I'm sure it improved something!haha
Thanks for all the suggestions and help guys. :thumbsup:
 

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PH, I hate to beat a dead horse but I was checking out the Black Magic web site and ran across the instructions to install their "Scavenger Airbox". This is a gutted type airbox that is open at the top and they recommend jetting up (5) sizes and raising the needle. I hate to see that honey have a cardiac arrest :(

Auggie
 

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Discussion Starter #15
The scavenger is probably flowing allot more air than what this is though, and I think jetting up 5 sizes is just to cover their behind. I'm sure that most people end up 2-3 sizes up tops in most conditions. It wouldn't hurt though for me to jet up, so I guess I should jet up about 2 sizes to around 460 mains.
As far as if 3 hp or any hp is worth it, YES! It is a free mod and is easy to do. If I were to get a 3 hp gain out of it (I doubt it, but it could be on top end) and get better throttle response, I will have the same gains as a set of $200+ reeds. It only took about 10-15 min. start to finish. The only thing is to watch your piston wash and plugs which we all should be doing anyway. I will most likely end up getting an EGT also for a little more ease of mind farther down the road. I have to get rid of my triple Digitron EGTs first and then will get a single.
Thanks for the concern and tips guys. :thumbsup:
 

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ph
go to slp the might have wat you are looking for
 
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