Buying a new intake

[BadBrian]

while looking for a new intake online I seen a few for a 350 the add read something like this chev 350 fits 57-86 87 w/ aluminum heads???What does the 87 aluminum heads part mean does it mean ??? I know that 87 means 1987 does it mean it will fit on aluminun heads also or only on aluminum heads??? Will they fit on a 1986 350 with regular heads???

[dirtnap]

it will fit an 86 but only aluminum head 87 because 87 cast iron heads had the center 2 bolts at a different angle