1971 R-code (Boss 351)
The Boss 351 is a high-performance variant available only in the 1971 Boss 351 Mustang. Rated at around 330hp (246kW), it was fitted with a four-barrel Autolite spreadbore carburetor, an aluminum intake manifold, and aluminum valve covers. It had four-bolt main block/caps and a premium crankshaft, constructed from high-strength nodular iron. The cylinder head was modified for better airflow and solid lifters were used. The forged connecting rods were shot-peened and magnafluxed for strength, and used stronger bolts/nuts. Forged domed pistons gave an 11.3:1 nominal (11.1:1 advertised) compression ratio. Ford manufactured 1,806 Boss 351 Mustangs in 1971, 591 of which are registered and accounted for on the Boss 351 Registry site.
The January 2010 issue of Hot Rod Magazine reported a project in which a Boss 351 was assembled to the exact internal specifications of an original motor, but fitted with open, long tube, 1-3/4" Hooker headers (vs. the stock cast iron manifolds), a facility water pump, a 750 Holley Street HP-series carburetor (vs. the stock 715 CFM Autolite unit), and minus the factory air filter assembly, engine accessories, or factory exhaust system. In that modified state, it produced 383 hp (286 kW) Gross HP at 6,100 rpm, and 391 lb·ft (530 N·m) torque (gross) at 4,000 rpm.[3] Actual "as installed" output (SAE Net HP) - with all engine accessories, air cleaner assembly, and complete factory exhaust in place, would naturally be expected to be far lower.
Oh, ok. Thank you. How long have you been in now?
4 years now and already on my second deployment. You are retired sf are you not?