N908RV
Well Known Member
Looking for any comments folks may have on this...
I have a Mattituck TMX - IO-360 with a 74" Hartzell blended airfoil CS prop and the newer MT (Jihostroj) governor. I've never been able to get more than 2,600 RPM in level flight. (Full throttle - approx 30" MAP at sea level).
I have an optical tachometer and on static run-ups I do get 2,600, which is about what I should be getting on a static test - generally 2,650 would be the upper end of what you normally get on a static test. I thought I would bump up the static RPM a bit to equally increase max RPM in flight. I adjusted the low pitch stop (on the prop) to the equivalent of an additional 100 RPM, but in static checks and in flight, I got no change. So, I returned it to the factory setting.
I double checked and made sure the prop cable allows for full max rpm (low pitch) and it hits the detent correctly on the governor. As the governor is preset at the factory (in theory) I hate to mess with their low pitch stop on the governor, although it is easy to do and easy to put back to the way it was.
But before I do that - anybody have any experience with this or comments about what RPM they are seeing with this engine/prop/gov combination?
As you can see, I've flown it quite a long time like this, but I have put it off long enough and I want to squeeze the last bit of thrust out of the engine (even though I'll barely ever use that RPM setting other than initial take-off) it would be nice to have it there if I need it.
Thanks,
Rob
I have a Mattituck TMX - IO-360 with a 74" Hartzell blended airfoil CS prop and the newer MT (Jihostroj) governor. I've never been able to get more than 2,600 RPM in level flight. (Full throttle - approx 30" MAP at sea level).
I have an optical tachometer and on static run-ups I do get 2,600, which is about what I should be getting on a static test - generally 2,650 would be the upper end of what you normally get on a static test. I thought I would bump up the static RPM a bit to equally increase max RPM in flight. I adjusted the low pitch stop (on the prop) to the equivalent of an additional 100 RPM, but in static checks and in flight, I got no change. So, I returned it to the factory setting.
I double checked and made sure the prop cable allows for full max rpm (low pitch) and it hits the detent correctly on the governor. As the governor is preset at the factory (in theory) I hate to mess with their low pitch stop on the governor, although it is easy to do and easy to put back to the way it was.
But before I do that - anybody have any experience with this or comments about what RPM they are seeing with this engine/prop/gov combination?
As you can see, I've flown it quite a long time like this, but I have put it off long enough and I want to squeeze the last bit of thrust out of the engine (even though I'll barely ever use that RPM setting other than initial take-off) it would be nice to have it there if I need it.
Thanks,
Rob
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