tuned airbox and exhaust for 912

[markmn]

Roger,

I was reading on the rotax site about the tuned airbox and stainless steel tuned exaust. Said they are required to attain the full 100hp.

 

I dont believe I have ever seen these installed on a light sport. then again Im not sure I was really looking for them either.

 

Can you enlighten us?

 

Mark

[markmn]

Roger,

 

Do most LSAs have the tuned airbox and exhaust?

Which ones do or dont?

Does it really make a performance difference or not?

 

Mark

[Angelitomon]

Hi Roger : I have a 08 ctls and dont have a tuned exhaust. What do you guys mean by the tuned exhaust.right now im looking for two tuned exhaust here in europe. One both from french companys. One is the one that does the tuned exhaust for dynaero , and teh other is one that was in air venture two years a go , scaitech.com.

Please give a look at them and tell me what you think.

Im probably going to fly yo annecy ( close to geneva) to have the ones that make the dynaero one make me a 3D scan of my installation to build an spacific one for my engine.

Its supose to give me an incease of 7% in power , 14% in fuel reduction and a 20% in noise reduction.

Thank yiu

Angel

[Angelitomon]

Thank you agian Roger.i have in my aircraft the stain exhaust,but i dont think that this one is tuned at all. Im talking about the doble flow exhausts with same distance on all tubes . Do this one snot work ar all? What a disapoint.

Thanks for the advise.

[207WF]

I think you should get it and report back to the rest of us how things changed, so we can find out on your nickel! Don't forget the LOA. WF

[Jeremy MacGregor]

Only about 10% of the slsa mfgs use the tuned aurbox and even fewer of the experimentals even mention it in there construction Manuel. The idea is to stablize the airflow between booth carbs by first running all intake air into a single filter and then ensuring that both carbs are having identical airpressure entering the venturi. This set up translates to a smoother running engine and thus in turn increases power very slightly. The other added advantage is the ports for the floatbowl vent lines. This ensures even pressure on the fuel in the bowls and allows for more even EGTs. These are two features that FD attempted to copy on the early SWs and there system works well enough.

 

Exhaust however is more critical. The power an engine can produce is heavily dependant on the amonut of back pressure the exhaust imposes on the cylinder. Too much pressure and the engine will choke down and lose power. Not enough pressure (which is the case in most twin exh. Setups) and you risk burning exh valves becuase the fuel is still burning as it leave the combustion chamber rather than burning completely inside.

 

The same principle with smooth running applies to the intake are along with the exhaust air exiting. (equal pressures= smoother operation and less oposition the engine had to throttle response.)