Hi All Following the carb-tuning question the other day, does anyone know if changing the oxygen sensor will automatically improve gas mileage and, if so, by roughly how much, % wise? My Caprice is 23 years old and has 151,000 miles on the clock and I'm getting 13-17mpg. The emissions on it are fine and well within the limits. Thanks PHILIP
I had a '86 Grand Prix 2+2 with the same LG4 motor, and a 3:08 posi. 180 thermostat, K+N air filter, flowmaster muffler w/dual outlets got me in the 20MPG range, and when the 200 let go, I got a 700, which was like adding a 1st gear! Ran with the H.O.'s! Timing chain, water pump and a few carbs, [worn throttle shafts] were the only things repaced in 230k miles, when I sold it!! Guy thought I was lying about the miles!!