Bill Ewing aka Ol' sarg' says.. I did a check with the Engine Test Cell guys at Aero Recip Canada yesterday. According to their books, the normal R1830-92 test-run is 48" Hg MAP & 2700 rpm for 1200 HP. (and here I quote) "Either the MAP may be increased by 1" Hg or the rpm by 100 to give the required test HP - but NOT BOTH.". I hope this straightens out a lot of the questions out there. The Overhaul Manual that I quote from is p/n 2051530, for Twin Wasp (R1830) C-Series Engines, original October 1952, revised July 1962.
Again to quote my Overhaul Manual, "The engine models covered in this manual are the Twin Wasp -C3G, -45, -47, -49, -51, -53, -57, -82, and -92."
P & W R-1830 Model differences:
-S1C3G:
91/98 fuel grade, carburetor type & settings
-45:
100/130 fuel grade, carburetor type & settings (ex-military)
-47:
100/130 fuel grade, carburetor type & settings
-49:
91/98 fuel grade, carburetor type & settings (ex-military)
-51:
91/98 fuel grade, carburetor type & settings (ex-military)
-53:
91/98 fuel grade, *reduction gear ratio & type, carburetor type & settings (ex-military)
-57:
91/98 fuel grade, carburetor type & settings (ex-military)
-65:
100/130 fuel grade, magneto type, carburetor type & settings (ex-military, built by Buick & Chevrolet only)
-67:
100/130 fuel grade, carburetor type & settings (ex-military, built by Chevrolet only)
-75:
100/130 fuel grade, carburetor type & settings, (ex-military, built by Buick only, plain main bearings, improved fin & muff arrangement, supercharge cooling, and accessory section.)
-82:
91/98 fuel grade, carburetor type & settings (ex-military)
-90D:
100/130 fuel grade, carburetor type & settings (ex-military, built by Buick only)
-92:
91/98 fuel grade, carburetor type & settings (-92 is the military equivient of the -S1C3G)
-94:
100/130 fuel grade, carburetor type & settings, (ex-military, improved fin & muff arrangement, supercharge cooling, and accessory section.)
-98:
100/130 fuel grade, carburetor type & settings, (ex-military, improved fin & muff arrangement, supercharge cooling, and accessory section, plain main bearings.)
