So Polaris new HO motor with the electronically controlled exhaust valves could this be done with the ECU?? Just have the sensor go off boost pressure
It needs to be on the far side of expansion chamber, the tuned pipe on a 2 stroke makes a 2 stroke work, with a super charger you can over pressure the intake over the pipe. On turbos you want to stay around 7 lbs max more in the pipe over the intake. This is why on a 28 series turbo they run a .82 ar but on a 3071 (on 800) you can get away with a .64 ar. But a .64 ar on a 28 series will create to much back pressure causing the opposite of a supercharger. The SC will basically blow it through and you don't get the right tune from the pipe. That's one reason why you don't see SC pushing big boost yet, or only in cases where the tuner knows his stuff. Now if you can control the pressure on both ends (I don't know for sure what's best but let's say 5lbs in pipe over intake) you could have a solid system with better economy and response, to unlimited boost.
It could be done mechanically but it could get tricky, if you used a smaller singer with tail and a 5lb spring. But then ran an intake boost line to the other side of diaphragm to equalize the pressure, so that the tail only opens when the exhaust side is 5lbs more than intake side.
Make sense.
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