A
Anonymous
Guest
Hi, all; Thanks for all the tips! 
My Fairmont's gas mileage (MPG) has gone from 14/18 (town/hiway) to a wonderful 16/22 MPG! It even has more power.
Here's what I've done:
1.) Tires carry 4 PSI over the recommended at 32PSI (factory=28 ).
2.) Sparkplugs as best: Autolite platinum, the ordinary-looking ones.
3.) Oil: Valvoline 10w40, 180 degree thermostat.
4.) Dizzy advance runs from spark port.
5.) Static timing = 11 degrees BTDC.
6.) EGR is connected (laws, you know...), but gives another +1.5 MPG without it....
7.) New catalytic converter (old one was plugged up).
8.) Cool air intake for the air cleaner.
9.) Clutch-driven fan (instead of flex fan). Better cooling, less drag.
10.) Idle is as low as practical: 550 RPM with A/C on (auto trans).
11.) Idle circuit screw just 1/8 turn lean from lean roll idle.
12.) Bonus: yellow-grommet Duraspark module adds even more MPG, but bumps me over the legal hydrocarbon limits by 2%-5%. (The emission laws here are stricter than the stock limits the car was designed for..
...politics, you know.)
13.) Automatic choke is backed off until it almost won't work on cold mornings, but I can live with that for $2+ gas.
14.) When I last pulled off the head, I installed the exhaust port divider and milled the head .010", plus went back to the steel head gasket and did some cleanup of the chambers, valve bowls and opened the exhaust port's ceilings a little. (This part raised CR to about 9.2 or so, over the stock 8.5, and netted about 1 MPG for my effort).
All in all, I'm pleased. If you're not stuck under emissions laws, try adding a used yellow-grommet Duraspark from a boneyard - see my post in this section on how to do it - and see how you do with it. You CAN adjust the idle screw (lean) to get under the limits, but it gets real hard to start when cold.
My Fairmont's gas mileage (MPG) has gone from 14/18 (town/hiway) to a wonderful 16/22 MPG! It even has more power.
Here's what I've done:
1.) Tires carry 4 PSI over the recommended at 32PSI (factory=28 ).
2.) Sparkplugs as best: Autolite platinum, the ordinary-looking ones.
3.) Oil: Valvoline 10w40, 180 degree thermostat.
4.) Dizzy advance runs from spark port.
5.) Static timing = 11 degrees BTDC.
6.) EGR is connected (laws, you know...), but gives another +1.5 MPG without it....
7.) New catalytic converter (old one was plugged up).
8.) Cool air intake for the air cleaner.
9.) Clutch-driven fan (instead of flex fan). Better cooling, less drag.
10.) Idle is as low as practical: 550 RPM with A/C on (auto trans).
11.) Idle circuit screw just 1/8 turn lean from lean roll idle.
12.) Bonus: yellow-grommet Duraspark module adds even more MPG, but bumps me over the legal hydrocarbon limits by 2%-5%. (The emission laws here are stricter than the stock limits the car was designed for..
...politics, you know.)13.) Automatic choke is backed off until it almost won't work on cold mornings, but I can live with that for $2+ gas.
14.) When I last pulled off the head, I installed the exhaust port divider and milled the head .010", plus went back to the steel head gasket and did some cleanup of the chambers, valve bowls and opened the exhaust port's ceilings a little. (This part raised CR to about 9.2 or so, over the stock 8.5, and netted about 1 MPG for my effort).
All in all, I'm pleased. If you're not stuck under emissions laws, try adding a used yellow-grommet Duraspark from a boneyard - see my post in this section on how to do it - and see how you do with it. You CAN adjust the idle screw (lean) to get under the limits, but it gets real hard to start when cold.
