>> My Forney F-1 is placarded against "sustained operation" between about 1900-2150 RPM.... The engine is a C-90.<<
I know of no justification for that placard. I'm going to go out on a limb here.? Maybe it's because the engine shakes so bad between 1900 and 2150 RPM? :>) Wayne -----Original Message----- From: John Cooper <[EMAIL PROTECTED]> To: 'va_couper' <[EMAIL PROTECTED]>; [email protected] Sent: Mon, 14 Apr 2008 6:06 pm Subject: RE: [ercoupe-tech] Re: Vibration question >> My Forney F-1 is placarded against "sustained operation" between about 1900-2150 RPM.... The engine is a C-90.<< I know of no justification for that placard. There was at one time an RPM restriction on short stroke Continentals with McCauley metal props, but it was rescinded in 1949. It never applied to the long stroke (C90 and O200) engines. John Cooper Skyport Services 4996 Delaware Tnpk Rensselaerville, NY 12147 518 797-3064 www.skyportservices.net
