You may find a date code cast in the block near the rear of the left head, it's probably Heco En Mexico but from what I have read it should be heavy cast with good tin and nickle and four bolt mains.


1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy