1963-1965 Exhaust Manifold Casting Numbers

1963

Left Right Engine
3749965 3750556 250 Horsepower
3749965 3750556 300 Horsepower with Powerglide
3797901 3797902 300 & 340 Horsepower with M/T
3797942 3797902 360 Horsepower Fuel Injection

1964

Left Right Engine
3846559 3747038 250 Horsepower with A/C
3846559 3747038 300 Horsepower with PG & A/C
3846559 3750556 250 Horsepower with M/T or PG
3846559 3750556 300 Horsepower with Powerglide
3846563 3797902 300 Horsepower with M/T
3846563 3797902 365 Horsepower without Air Conditioning
3846563 3797942 365 Horsepower with Air Conditioning
3797942 3797902 375 Horsepower Fuel Injection

1965

Left Right Engine
3846559 3747038 Early 250 Horsepower with Air Conditioning
3846559 3747038 Early 300 Horsepower with Powerglide & A/C
3846559 3750556 250 Horsepower
3846559 3750556 300 Horsepower with Powerglide
3846563 3797902 300 Horsepower with Manual Transmission
3846559 3747042 250 Horsepower with Air Conditioning
3846559 3747042 300 Horsepower with Powerglide & A/C
3846563 3797902 350 & 365 Horsepower without Air Conditioning
3846563 3797942 300 Horsepower with Man. Trans. & A/C
3846563 3797942 350 & 365 Horsepower with Air Conditioning
3797942 3797902 375 Horsepower Fuel Injection
3856301 3856302 425 Horsepower 396 Engine