I will be working on tuning a version of the mod for the new Flysimware Cessna 414 tomorrow. In doing some preliminary research on the engine, I’ve found conflicting information. Does anyone have an operating manual or technical specifications for the RAM IV engine conversion which Flysimware is modeling?
An online POH for the C414a indicates that the original engines had the following specifications:
Continental TSIO-520-NB
Power: 310 HP per engine
Maximum Manifold Pressure: 38 inHg
Critical Altitude: 20,000 ft.
(source: C414A POH Pdf | Redcliffe Aero Club)
The Flysimware manual has different specifications:
Continental TSIOL-550A
Power: 345 HP per engine
Maximum Manifold Pressure: 41 inHg (red line on the manifold gauge in cockpit)
Critical Altitude: ???
(source: https://flysimware.com/website2019/wp-content/uploads/2022/03/Cessna-414AW-Manual.pdf)
Interestingly, the TSIOL-550 is a liquid-cooled engine (that’s what the “L” stands for in the model name). Is this a typo in the Flysimware manual? The RAM IV engine modification is air-cooled, and it is based on the TSIO-520-NB engine. (source: Performance-414A — RAM Aircraft, L.P.)
Another wrinkle is that at least one of the included liveries has a “RAM VII” decal on the winglet. The RAM VII conversion features a different turbocharger, as detailed here: Legendary RAM Engines for Cessna 414As — RAM Aircraft, L.P.
Since the real-world aircraft originally shipped with the TSIO-520-NB, and the Flysimware manual states that the aircraft is modeled on the RAM IV conversion, I think it’s safe to assume the following specs:
Maximum Manifold Pressure: 41 inHg
Critical Altitude: 20,000 ft.
If anyone has further information, I’d be interested to know whether the RAM IV conversion affects the critical altitude (is it higher than 20,000 ft?), and any details on the fuel metering system (i.e. does it compensate for decreasing manifold pressure above the critical altitude?)