Parts Source, Napa Auto Parts, Canadian Tire
best thing about the K&N air filter is its good for the life of the car, just clean it yourself after every 80,000km's with a $10 cleaning kit. Pays for itself eventualy.

 

i was running over 1200w RMS in my 99Grand Prix GTP and had NO issues with that causing any milage issues. that was with 200+lbs of gear in the back (poor rear suspension). anyway like i said that should be NO cause for a noticable change in MPG in that car.
something else must be wrong, time for a tune up for sure.

 

O it was your car that i got my gas form .......sorry about that LOL

 

if you wanted more bass build a proper ported box

 

time for a tune up for sure and a lock on the gas cap

 

He is ok,hes running it at 4 ohms,prolly more around 300wrms to 4 ohms.....

 

300 rms on your average amp is about 50A of current draw, which when added to your hu draw is probly closer to 60A added for your stereo... 60A @ 12v is 720 watts of power drain, since 1 hp is 746 watts, you're adding probly over 1 hp to the power your engine needs to produce all the time, even at idle, so your gas mileage will decrease, especially with in-towne driving.

 

It may have been mentioned allready in this thread but i read on a site one time that for every 10 amps extra drawn from the alternator reduces gas milage approximately 1/2 mpg.

I,ll see if i can find it.

 

Maybe in a Geo Metro, but running 6x175 and 1400 watts on subs hasn't changed a thing in my car.