[kennybobby]

i like measuring manifold pressure, aka vacuum, with a big fat analog gauge. It's quick and easy--put a tee in a line coming off the throttle body and run a hose to the dash and it's working.

i drive a bigass van that got 14 mpg for years and years before i got saved. After i got converted to the ecomod religion my mileage is closer to 17 mpg using all the tricks: pulse and glide, coasting in neutral, staying off the brakes, and quickly accelerating with high load as indicated by the vacuum gauge.

i don't always accelerate, but when i do i drink dosx... i make sure the engine is pulling hard at or near it's most fuel efficient region (i.e high manifold pressure = low vacuum).

When driving i don't need to know or read any numbers in real-time, just look at the needle and adjust the throttle such that it's either floating up in the high vac, or i bury that thang down low when under load.