I was getting at a defined standard so that your numbers could be compared to a certified a/c engine. Wikipedia defines SAE hp, depending on the configuration of the engine being tested, as follows:
SAE gross power[edit]
Prior to the 1972 model year, American automakers rated and advertised their engines in brake horsepower (bhp), frequently referred to as SAE gross horsepower, because it was measured in accord with the protocols defined in SAEstandards J245 and J1995. As with other brake horsepower test protocols, SAE gross hp was measured using a stock test engine, generally running with few belt-driven accessories and sometimes fitted with long tube test headers in lieu of the OEM exhaust manifolds. The atmospheric correction standards for barometric pressure, humidity and temperature for testing were relatively idealistic.
SAE net power[edit]
In the United States, the term bhp fell into disuse in 1971-72, as automakers began to quote power in terms of SAE net horsepower in accord with SAE standard J1349. Like SAE gross and other brake horsepower protocols, SAE Net hp is measured at the engine's crankshaft, and so does not account for transmission losses. However, the SAE net power testing protocol calls for standard production-type belt-driven accessories, air cleaner, emission controls, exhaust system, and other power-consuming accessories. This produces ratings in closer alignment with the power produced by the engine as it is actually configured and sold.
SAE certified power[edit]
In 2005, the SAE introduced "SAE Certified Power" with SAE J2723.[20] This test is voluntary and is in itself not a separate engine test code but a certification of either J1349 or J1995 after which the manufacturer is allowed to advertise "Certified to SAE J1349" or "Certified to SAE J1995" depending on which test standard have been followed. To attain certification the test must follow the SAE standard in question, take place in an ISO9000/9002 certified facility and be witnessed by an SAE approved third party.
So, if I understand you correctly, you are looking to determine "SAE Net HP", which is measured at the flywheel, and includes air filter, accessories, stock exhaust, etc. Without these "additions", you would be talking "SAE Gross HP".
Mark