This car has been hobbled together by so many different cars it's not funny. Previous owner did some weird engine part combinations putting the 1.6l SI fuel system and ecu on the motor so that's probably hurting my mpg but when I ran her on bald tires my highest recorded mpg was 55mpg, but after she slid off the road in the rain around only 30 mph I decided to get new tires.
Went with a lightweight cheap AGM battery, was having issues with engine off night coasting cause of it but now I am using a permanently mounted and wired in jump start battery to supplement at night to prevent that. So still lighter than stock battery. As soon as I cut the engine, I hit the button to cut on the jump battery and it auto turns off when the engine starts back up. I charge it back up during the day through cig lighter.
I didn't mount it for this purpose, just did it cause I always had it in the car anyways and thought it would be convenient so using it for this purpose is a bonus.
Just listing all modifications to car, eco or not
Air/Fuel Ratio Gauge
Tire Pressure/Temps Sensors and monitor
Cold air intake
Performance Exhaust Headers/Factory Cat Delete
Cheap Amazon high flow cat added
Large aftermarket muffler
1.6L SI intake manifold/throttle Body/Fuel Rail/Injectors/ECU
Front and rear strut bars
Front aftermarket struts (slightly lowered front)
Front aftermarket Stabilizer bar (stiffer, lighter)
Front aftermarket radius rods
12 pound AGM battery
3 pound jump start battery mounted & wired in
Half size radiator
Plastic tub lid covering half the grill from inside
39 PSI tire pressure
AC compressor belt removed (AC is broke but plan to repair)
Rear wheel skirts
small rubber spoiler you 3m tape on but instead of on the trunk I'll put it on the hood to direct airflow over wipers
Every mod below here I have, but are not on yet
Carbon fiber vented hood
Engine swap to VTEC D series engine.