The 350/361 version of the B engine came out in 1958 (Sonoramic Engines) and the RB as a 413 was available in 1960-a good example is the one running in NMC. The low deck 400 is derived from the 350/361 roots as was the 383- RB had a 383 (60-61 I think), 413 , 426, 440. All parts interchange with the exception of the pistons obviously and the distributors. The intakes are different B to RB. (of course pistons, rod length, crank main journals differ)....basic answer is yes the B is legal from 1958, RB from 1960 |