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I chose to drill four 1" holes in the back/bottom of the air box as apposed to a bunch of little holes. I figured it would be easy to find plugs to insert into the hole in case I didn't want to leave it that way. That should be about 3 square inches, so I don't know if that is enough to do much good. I haven't had much chance to really test it out, but it seems to be a little easier to roll on the throttle from the closed position without such a sudden jerk. Seems to have more get up and go too, but not a major difference, but it does remind me of the way the Rochester Quadrajet sounded on the 350 in my '77 Regal! :D:D

I have a K&N filter, drilled baffle plate in exhaust (cat converter is still in place) and a Vance and Hines Fuel Pak to manage it. Here's a couple of pictures to see where the holes were drilled. You can't see two of the holes when the box is mounted, and the other two are hard to see unless you are looking for them.






 

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I chose to drill four 1" holes in the back/bottom of the air box as apposed to a bunch of little holes. I figured it would be easy to find plugs to insert into the hole in case I didn't want to leave it that way. That should be about 3 square inches, so I don't know if that is enough to do much good. I haven't had much chance to really test it out, but it seems to be a little easier to roll on the throttle from the closed position without such a sudden jerk. Seems to have more get up and go too, but not a major difference, but it does remind me of the way the Rochester Quadrajet sounded on the 350 in my '77 Regal! :D:D

I have a K&N filter, drilled baffle plate in exhaust (cat converter is still in place) and a Vance and Hines Fuel Pak to manage it. Here's a couple of pictures to see where the holes were drilled. You can't see two of the holes when the box is mounted, and the other two are hard to see unless you are looking for them.






Honestly do u think the fuel pak is doing anything? I too have the modded airbox/exhaust on my 950. I drilled 2 2" holes on either sides and am running a straight pipe exhaust. I have NO processor just stock ecu. The dealer and various mechanics I know told me I didn't need one until I went with bigger diameter pipes. Also that the mods to the air box were in no way close to that of a true BAC. Just curious if you can tell or of its just a precaution for you?

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Also....consider putting some holes in the areas marked. Closer to the filter and drawing in outside air rather than hot air from the motor.

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Discussion Starter #6
Honestly do u think the fuel pak is doing anything? .............Just curious if you can tell or of its just a precaution for you?

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Partly a precaution and partly to smooth out the jerky throttle response at low speed, but the motor has to be running cooler because the fan rarely comes on now. Now it doesn't matter what I change, the processor will sufficiently compensate. I plan on changing exhaust soon. Besides, my brother was a supervisor at Vance and Hines, so I got it at his cost, which was REAL cheap! :) I wanted to buy it before he left.


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Partly a precaution and partly to smooth out the jerky throttle response at low speed, but the motor has to be running cooler because the fan rarely comes on now. Now it doesn't matter what I change, the processor will sufficiently compensate. I plan on changing exhaust soon. Besides, my brother was a supervisor at Vance and Hines, so I got it at his cost, which was REAL cheap! :) I wanted to buy it before he left.


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Nice on the family discount. See my 950 doesn't have the jerky throttle so o don't know that struggle. I'll get one for sure once I (if I) get bigger pipes. I like my drag pipe now so....anyways, where I got my holes made a big diff fast. Its allowing cooler air in right below the filter. Thinking about adding a few more.

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yeah, I like discounts :) I was trying to put the holes where they aren't readily visible, and I thought the two on the bottom would bring in cool air, plus the upper left hole isn't terribly close to the motor. I'll put it through the paces and decide if I need more.

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yeah, I like discounts :) I was trying to put the holes where they aren't readily visible, and I thought the two on the bottom would bring in cool air, plus the upper left hole isn't terribly close to the motor. I'll put it through the paces and decide if I need more.

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Can't see em from looking straight at bike. And mine are 2" holes. But yea u may find that's enough that u have there....

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See mine are 2" holes. I'd like to find something like these but luckily not much of anything can get in. Checked the other day after almost 9 months and clean.

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Update: Seems like I have more torque at all speeds, especially lower rpm's, and the engine seems to be a lot smoother with less vibration at all speeds......not that there was a large amount before, but there is less now. Fuel economy seems to be the same.

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I'd like to thank both mccuthan and boob for posting these threads on their modded air boxes. I added a new k&n air filter to my 09' 950t and could tell a mild improvement in performance. I then drilled 1" holes on the both the front and back of the black housing on the stock airbox. I kept both holes close to the chrome cover so as not to suck in hot air from the motor. Just before the thunderstorms hit, I took it out for a spin. I could definitely tell a difference thru the entire power band. This is why I'm such a fan of this forum, we all try to help one another. Thanks boob for answering my PM's, and thanks mccutchan for postings.

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Great job and you are quite welcome! Now just imagine what 2 or 3 more of those holes or one 2" hole above each 1" would do. Def need at LEAST one more 1" hole on both sides. Trust me....you need it. :)

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This is why I'm such a fan of this forum, we all try to help one another. Thanks boob for answering my PM's, and thanks mccutchan for postings.

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That's what it's all about. :) Almost 100% of what I learn about these bikes comes from the forum. And yes, it is fun making low cost home-grown mods. I'm building a ratted-out Honda VLX bobber, and everything I have learned has been from these forums.
 

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Nice job RM, great photos too.
I drilled mine in a similar way, think yours is more neat for sure.
I have to take a photo soon, not as neat as yours *L*.

I did 6- 3/8s holes in the back (engine side) of the box last year or before. I also thought with that size I could plug it up if need be. But its a GREAT mod and if I put my finger over a hole with the bike running and rev the engine I can certainly feel the air getting drawn in.
 

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I support everything said above ;) love the forum, love the DIY projects, love riding!

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