usually mods that increase air into the engine will cause the computer to increase fuel injected to the cylinders, resulting in worse mileage. this is why gas mileage on a cold day is so terrible. the cold air has more oxygen per unit volume, so more fuel is used to keep a good mixture. car feels a bit more powerful but uses alot of fuel. on a civic i doubt you would see a difference tho with intake and exhaust mods. my 02 civic has intake/header/exhaust and i still get around 24 city/40 highway. it depends more on how you drive like stepping on the gas pedal.
I was getting 42+ highway miles and 35 city with a turbo. That was even playing some, however playing a lot led to 25 mpg. K-pro and a tune for mileage will help greatly. 40mpg is probably not out of the question. Other than that you are just looking at things that make the engine breathe easier. K&N drop in filter. New spark plugs. Lighter wheels will help some as well, along with a lighter flywheel. I don't know how open to it you are, but deleting AC and PS will give you better mileage.
__________________ ~Boosted EM-2~ (gone)
B16 Del Sol - (gone)
94 M-edition MX-5 - Supercharged roadster mountain carving toy (that I DD)
i forgot to mention, altitude also matters. hi altitude means much less air so the car gets better mpg compared to sea level. also depends on the roads you drive, flat roads obviously will give very good mpg cause you dont have to push the car as hard as going up hills. with a few boltons, chances are mpg will stay the same or slightly increase, so long as you do not drive the car harder to hear the intake.
on our cars theres not much you can do to get much better, or much worse gas mileage. you can increase or decrease a bit, but for the most part on average, you wont change it by much no matter what you do (unless you start messing with engine settings).
if you really want to increase gas mileage, from now on dont push your pedal very far past halfway, and never floor it. it will take you way longer to get up to speed from being stopped at a light, but youll definitely save gas. i GUARANTEE that will save you more gas than any modifying will.
'02 Si-G Veloz Edition ~ Canada
HP 4-1 race header - AEM Short ram intake - Tsudo N1 2.5" catback system - NGK Iridium IX spark plugs - OBX Racing strut tower - 4 ga. ground kit - Drag DR-19 17" rims - Kumho Ecsta AST 215/45/r17 tires - 8000k HID kit - Varad led custom street lighting - McMaster trunk shock kit - Pioneer deh-p5900ib deck - Alpine Type-S 12" sub - Phoenix Gold mps-2500 amp - Infinity Kappa 692.9i 6x9 speakers
anyone have a driver side door lock actuator for sale? PM me