Has anyone removed/modified the Airbox on an F3 to improve intake airflow? Ideas?

[Cobranut]

I did a search, but didn't see anything similar.

Has anyone removed the huge airbox on the F3S and installed a duct and conical filter to increase filter area and get cooler air into the throttle body?

I notice my IAT often runs 10 degrees hotter than ambient air, and getting that huge bulky box out of the way when servicing would be nice as well.

 

[AndysF3S]

The airbox on my 22 F3S draws outside air from the left side and the hole for the incoming air is larger than the duct to the throttle body so I can't see an after market anything that would improve that. I am not aware of any after market air intakes for your machine. FWIW

 

[Cobranut]

The airbox on my 22 F3S draws outside air from the left side and the hole for the incoming air is larger than the duct to the throttle body so I can't see an after market anything that would improve that. I am not aware of any after market air intakes for your machine. FWIW

Thanks,

Just thinking of the small filter area, as well as making servicing much easier in the future.
I'll probably install a K&N filter at the least, and I may see if I can fabricate a duct to direct fresh air from outside the bodywork to the inlet.
I does seem to suffer from a bit of heat soak in hot weather.

 

[BajaRon]

While I know it would take a dyno to confirm this, I am not sure that an intake modification would not afford some worthy performance improvement. Especially if coupled with other upgrades like less restrictive exhaust and ECU flash.

As you can see in Picture-1 below. The inlet path is not huge. Nor will the final airbox inlet (located top left corner) feed the 3 intake manifolds evenly. Cylinder 2 and 3 are left with a longer, and most likely, depleted volume path. This after incoming air has traveled through the filter, filter box, and adaptive tubing (Picture 2). All of which will tend to increase heat soak and volume density. Not to mention, making servicing of spark plugs, fuel injectors, and coil packs more difficult.

Now making a system that is compatible with the sensors, ECU, etc, that's going to be a challenge.

 

[Peter Aawen]

True, there's all that ^^, but if I was a betting man, I reckon that if asked, the ROTAX Designers/Engineers would say that the size/volume of the intake tract & ducting is all there for a reason; and in fact, it carries out some essential purpose, probably something along the lines of 'providing sufficient volume of air to allow the engine to draw on that large volume of air whenever the rider (suddenly?) increases throttle demand, in order to avoid engine hesitation or something similar; but in reality, it's probably more likely to make it possible for the engine to pass/exceed some emission level or noise/decibel limit...

Just Sayin'

 

[BajaRon]

Could be. But engineers are typically tasked with more than 1 parameter. For example, the emissions systems on current day cars not only increase fuel consumption, increase complexity, reduce dependability and life span, but add a significant cost to the machine as well as maintenance throughout its shortened life.

The main purpose of the air boxes on the Spyder are to reduce induction and intake noise within the confines given by the space available. I can pretty much guarantee that performance is not the primary concern here.

But again, only the dyno will tell.

 

[Dennis in Lodi]

I was part of the testing for the Monster Fuel flash. We had a Dyno and a Daytona that allowed wheel spin. Right out of the box there was slight improvements with the K&N filter. The FINALE air box mod consisted of two 7/8" holes drilled into the filter lid which again delivered very slight Dyno gains. As Peter stated above, every other air box mod attempt resulted in significant negative results across the low and medium rpm range.
Watch this video to see and hear the end results with the Monster flash, two 7/8" holes, and K&N filter.

RT SE6 Tests

This is "RT SE6 Tests" by Monster Fi on Vimeo, the home for high quality videos and the people who love them.

vimeo.com

Here is where you can get the flash

ECU Tuning

We put the Power in Powersports.

www.monsterfuelinjection.com

Good luck. Dennis

 

[troop]

I also can tell you that the two drilled holes do allow more air into the intake. On my prior F3S, before I had a custom tune on my PV3 equipped Spyder, I drilled the holes into the air cleaner cover. When riding it around, the Spyder would noticeably fart and pop on decel. After datalogging a custom tune, the F3S ran like a champ. I'll likely be buying an extra cover to drill the holes when I datalog a new tune for my RT S2S.

 

[Dutchy]

From what I remember from the ADF, if it is not broke, don't fix it.

 

[BajaRon]

From what I remember from the ADF, if it is not broke, don't fix it.

If we all took that approach, we'd still be walking... There is always a better mouse trap out there. Finding it is the key.