Just bought a 2000 si civic, 69,000 miles, intake and exhaust mods only. Was wondering what type of gas milage should i hope to see, and with what driving conditions. City/hwy. Thank you for the response.

 

in my 2000 ex i can go around 275-300 before filling up. I get around 32-33 mpg(mixed city/hwy) nothing changes really from all city or all hwy.

I would assume it would be close, but not as high, maybe 30 mpg.

 

si gets worse gas mileage because its more sporty. it gets about 25 city 29 hwy (driving grandma style)

 

my friend get 26 city and 28 highway. he installed air filter and intake on his civic.

 

well mods usual don't help MPG... if anything they USUALLY HURT MPG... just due to the fact that you like that exhaust sound... you like that air intake sound so you hop on the gas harder more which is what hurts the mileage.LOL

but if you don't drive like a mad man all the time, id say 24-30mpg estimated. but it all depends on how much you coast your car, how hard you hit the gas, how much pedaling you do on and off, as well as your highway speed.

just do what you can... check air pressure in your tires, fill up the tank all the way, clear your milage trip meter, then drive the tank down to around 1/4tank of gas and fill it up and take that trip milage to how much gas you where able to put in the gas tank to top it off and thats your mileage at that time... its best to ALWAYS check your mileage every tank of gas. this will show you how hard youve been running your car and if you have any problems.

 

+1 addiction2bass . Deff. make sure you tires are at the correct pressure, airfilter is clean, and do what he said with the trip odometer.

 

I have a newer si and I get 320 if I baby it. My buddy has a 2000 si and gets anywhere from 275 -300 depending on how he drives it.

 

From an Si you should probably expect over 25 mpg if you're not racing it around town. Time and place for everything...