1 to 2 barrel swap

i theory the 2 bbl will get better MPG cause the air speed in each bore is higher mixing the air and fuel better. and the 2 bbl has better design fuel circuits. my 64 225 gained 10-20 HP with a 2 bbl, on that engine it is a lot. the 1 bbl on the / 6 and 2 bbl on the 318 have 2 screws that go from the top casting thread into the bottom casting. be sure to NOT over tighten them. that will cause the casting to warp. on the 2 bbl set the float level to 1/4". from the top of the float to the top of fuel bowel casting.