flyrotary@lancaironline.net Mailing List Archive

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The stock waste gate controller is about as light as it gets and you shouldn’t run into any problems with the ~5-7 psi it usually dishes out. But if you wanted to decrease the boost you could lengthen the actuating arm a little or change out the spring.

Install the stock waste gate controller, Rusty. It does little good to have a turbo that doesn’t produce any boost and you can easily control your manifold pressure with the throttle (every turbo car runs just fine idle). Also, keeping that waste gate closed at low power settings will help quiet the exhaust.

David Leonard

Thanks for the comments David. At the moment, I've got a manual cable hooked up to the wastegate, and will be leaving it fully open for initial testing. I've tried closing the wastegate at about 2000 rpm, and could hear the difference in sound, but it wasn't that significant.

I asked Bruce how much pressure he thought I could safely run with 9.7 rotors, and he said 2-3 psi (32-33 MAP). For now, I will do everything possible to stay below that limit, which is why I have a relief valve that's holding me to 3 psi. Clearly, I don't want to keep the relief valve set so low, but it's already saved my engine once, so it stays until I prove that I can control the boost manually during flight ops.

Eventually, I'll probably try a normal wastegate actuator, but I'll want the lowest possible spring pressure. On the other hand, I may find that my fully open wastegate will still give me 5-6 psi of boost, so getting a lower spring pressure on the actuator would be a waste of time. Yep, lots of experiments to perform, and data to collect.

Cheers,

Rusty