Mileage (Legitimate Intake/Exhaust Queston)

[Dewey]

Just got back from about 400 mi. of highway driving and hit the all time highest "miles per tank" # since I bought my car. Would've hit 300+ if I didn't fill up at my last opportunity. But 286 was what I was at w/ about 1/4 of a tank left. As you can see from my sig. I have the FTRA + the Whisper Lid. What I'm wondering is how much do you think this will decrease once I get a Borla catback? If I'm thinking correctly, I can only imagine it'd go down, but still be better than stock? Is my assumption correct? Current setup = more intake than exhaust, but the Borla would even things out I'm sure. Can anyone explain how this might work?

[Arctc Wolf]

no, it'll probly stay the same if not go up since you'll be increasing the engines volumeteric efficiency. it won't have to work as hard to get the exhaust out of the pipes, and there won't be as much leftover exhaust in the cylinders, allowing more air to come into the intake. On top of this, the engine will run cooler since all the hot exhaust gasses can escape easier out the pipes.

[strange_trp]

probably stay about the same.

i'm not so sure about that volumetric efficiency statement. see the 3" exh debate where this has been discussed ad nauseum.

speaking of mileage, i got 340 and still had about 2 or 3 gallons left in the tank. of course this was like 90% interstate and i was pretty easy on the gas, but 300+ is a reasonable expectation for a tank.

[Dan M]

Off topic, but just some information for you. [img]smile.gif[/img]
It's not a big deal for my car to get up to 350 miles out of about 12-12.5 gallons of gas.

[Dewey]

so wtf is wrong w/ my car? Is there a break in period that gives me shi**y mileage? I mean, i do a lot of city driving, not so much hwy. But 230-250 city miles per tank seems pretty damn low.

[strange_trp]

a lot depends on your driving style. if you run it up to 3500-4k accelerating from every stop, you can't expect great mileage. a full tank around the city will get me about 260 miles because i get the rpm's up there all the time.
but on the interstate when i'm getting paid 36.5 cents per mile and i'm on the clock, i take it easy on the gas, keep plenty of good cd's to keep my head occupied, and use the cruise control and then i get 300-350 consistently. it would be better than that if i didn't run WOT on every entrance ramp. [img]smile.gif[/img] can't help myself.

[magic1872]

i drive mostly around the city and i get anywhere from 24-29 miles per gallon