Does anyone have before and after experience to share about the Rotax 912ULS tuned airbox option?  Did you experience a performance increase?

The specifications claim an additional 5hp with the addition of the airbox. 

Views: 512

Reply to This

Replies to This Discussion


I do not know about the performance gain, as I have always had the Rotax airbox since the original build. But it does provide a good way to incorporate carb heat , with the linked butterfly valves. 


I have been wondering about the benefit of the tuned airbox too. It is an expensive option but an additional 5hp would be nice to have.
I will look for more info on the Rotax Owners website. If I can't find the answer there then I will post a question on their website. I will share any results here.
Would be interested in more info on this myself ,will keep watching

I will say that being more important for getting the rated power from a Rotax is to get the RPMs up. I thing most people more than likely over pitch the prop.




New from Zenith:

Zenith Planes For Sale 

Classified listing for buying or selling your Zenith building or flying related stuff...


Weather Maps

Custom Instrument Panels
for your Zenith

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, power distribution panel, Approach Fast Stack harnesses, Dynon and Garmin avionics, and more.

Custom Upholstery Kits for your Zenith Aircraft:

Zenith Vinyl Upholstery Kits

Zenith Apparel from EAA:

Zenair Floats

Flying On Your Own Wings:
A Complete Guide to Understanding Light Airplane Design, by Chris Heintz

Builder & Pilot Supplies:

How to videos from

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit for the latest DVD titles.

Aircraft Insurance:


West Coast USA:

Pro Builder Assistance:


Transition training:

Golden Eagle Aviation

Pianosa Flying Farm

Aircraft Spruce & Specialty for all your building and pilot supplies!

© 2020   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service