Hi Dave,

 

 

However, I am a bit confused, I notice your have a 13B, yet you use 222CFM at 3000 rpm - which is about twice what you should be getting out of a 13B, I get about 153 CFM.  Wait! 153*1.6 = 244 CFM, Ok I see where you are coming from. Now the crucial question is - does your engine produce enough exhaust mass flow to drive the T06H turbine wheel fast enough to produce 1.6 pressure ratio at sea level? If it does then 6000 rpm underload will likely produce much more than 1.6 pressure ratio.  What I am saying is if you could get 1.6 at 3000 rpm then you would unquestionably need a waste gate to keep from blowing your engine at 6000 rpm under load.

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Ed Anderson