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Modified air box

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bbk2001

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I was looking to add this mod to my gen 2 vmax. Ultimately I want the mab plus akrapovic exhaust system with gurued gear flashed ecu.

Is this something I purchase or do I modify the air box myself?

Thanks for any info!
 

Itgoes

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Watch this:
That is the basic airbox mod or MAB. Very simple to do on your own with a razor knife.

There is another air box modification called the TT (Triple Threat), that involves cutting some holes on both sides of the airbox and adding 2 additional filters. It inexpensive but requires more labor. It will make more power than the MAB.
 

cleanfreak62

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Please let me know how cutting two holes in the cover of the airbox is an advantage. As I see it it takes away the whole ram air effect because instead of pressure being built up and forced into the air filter it will pass right through the two holes.
 

Itgoes

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Please let me know how cutting two holes in the cover of the airbox is an advantage. As I see it it takes away the whole ram air effect because instead of pressure being built up and forced into the air filter it will pass right through the two holes.
The VMax does not have ram air. It does not produce any significant pressure in the airbox, the airbox is dust proof but not sealed for pressure. In addition ram air is only effective at very high speeds like 90+ MPH even on purpose designed systems. You could I guess call the scoops feeding the airbox a "Cold Air System" as it does draw ambient temperature air into the the intake. I think this is beneficial because a lot of heat gets trapped under the faux tank.........the top of the engine is of course right under there and coolant pipes run right next to the air box (I made my best attempt to insulate those).

What the addtional holes in the air box does is double filter area reducing air intake restriction.

It's been proven that a modified airbox does signifcantly increase power especially if you add an aftermarket exhaust, and tune for the extra fuel and air.
 

why2kmax

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I think the trumpets in the OEM airbox are the key to the midrange torque. The MBA kit pod filters allows the most air of course but the air is not streamlined or maybe better to say it doesnt develop the velocity as quickly as the trumpets, so you dont develop as much midrange torque, but do get more HP in the very high RPM ranges. Thats why MBA is best for drag racing but the modded airbox is better for everday riding where you spend 90% of your time in the 2500-4500 rpm range. Having sad that Ive never ridden a max with a OEM airbox or modded one so I cant confirm.

BUT I did replace the stock airbox on my KTM 1290R (and did all the exhaust and ECU stuff we talk about here) and the Rotty airbox had different height trumpets, which depending how short or tall they were, moved your powerband and HP/Torque numbers around a bit.
 

Itgoes

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I think the trumpets in the OEM airbox are the key to the midrange torque. The MBA kit pod filters allows the most air of course but the air is not streamlined or maybe better to say it doesnt develop the velocity as quickly as the trumpets, so you dont develop as much midrange torque, but do get more HP in the very high RPM ranges. Thats why MBA is best for drag racing but the modded airbox is better for everday riding where you spend 90% of your time in the 2500-4500 rpm range. Having sad that Ive never ridden a max with a OEM airbox or modded one so I cant confirm.

BUT I did replace the stock airbox on my KTM 1290R (and did all the exhaust and ECU stuff we talk about here) and the Rotty airbox had different height trumpets, which depending how short or tall they were, moved your powerband and HP/Torque numbers around a bit.
Yes.

The factory airbox has the YCCI (Yamaha Chip Controlled Intake) system. Each TB opening has 2 stacks one on top of the other to form a tall stack. That is best for low and midrange power and TQ. At around 6500 rpm the top stacks lift, leaving short stack which are best for max HP at high rpm. This provides a very linear powerband that gets the most out of the engine through the entire rpm range.

The Monster Big Air Kit has shorter shorter stacks and huge filters so that there is essentially no air restriction whatsoever. This is great for high rpm power but by removing the YCCI there is a loss everywhere else under 6K rpm.

The TT Mod attempts to get close to the minimal restriction of the MBA but keeps all of the low-end power.

The MBA stacks ar very nicely machined smooth aluminum, and were designed to maximize velocity so they do have a slight advantage over the TT Mod for max HP. I don't know of a dyno back to back of the 2 systems but it could be as much as 5 HP would be my guess. But, below the curve there are a lot of areas where the TT Mod is making 10 HP more. In fact just the factory air box will make more HP and TQ everywhere under 65000 rpm than the MBA.

Watch Tim Nash's great video:

 
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why2kmax

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my winter project may be to do the TT box and go that route then get Tim to reflash the ECU and see how it is. I have the stacks, and the air box but I DONT know if the guy I bought the bike from gave me all the intake parts and I would need to figure out how to make the stacks work again. One thing I can confirm, Tim said the TBs will give you a headache with it wide open, absolutely. At WOT with me down low next to the airbox cover even with a helmet on and earplugs its sometimes painful. Man its LOUD
 

1badmax

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Looks like it was the first time it had been opened at 5500 miles.
 

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