Gas mileage after X

[jas142]

Anyone else notice a decrease in gas mileage after the O/R x? I also seem to feel that its running kinda rich.

 

[JonJon]

decrease
i think i'm rich too
still waiting to get dyno'd

 

[cap42]

Ya I lost some gas milege and I'm running a bit rich not horribly just lost about 20-30 miles per tank...still haven't gotten a tune either

 

[GoBabyVroommm]

When i put the o/r h-pipe my gas mileage got better. It wasn't tell i got on it it went down faster but that is only because it gave me more hp. The x pipes gives you more hp than the h pipe. Your gas will go down faster if you floor the car.

 

[JonJon]

When i put the o/r h-pipe my gas mileage got better. It wasn't tell i got on it it went down faster but that is only because it gave me more hp. The x pipes gives you more hp than the h pipe. Your gas will go down faster if you floor the car.

my gas went down on long highway trips where i avg'd 23mpg before on 450 mile trip
but now i get 20mpg on the same trip

 

[road rage]

I've noticed a decline in gas mileage since the x pipe and I too am running a little rich.

 

[4.6MustangSteve]

I have noticed a bit of a decline in mileage... It's not much, though... Maybe 20 miles per tank.

 

[Ryan02Stang]

I'm glad im not the only one noticing this...i noticed about 30 miles less per gallon after the O/R X...i need a tune!

 

[yamie700]

I noticed a little decline in gas mileage also, probably mostly due to me giving it more gas just to hear the exhaust though
I thought that our stock computers would adapt to the new pipe and eventually lean things out a little?? I do have MIL eliminators on though so maybe that would cancel out the computer being able to adjust?

 

[8yourZ06]

Just thought I would make mention of this if anyone was interested. Your car seeming to run richer and the fact your gas milage decreased go hand in hand. Your rear O2 sensors are not heating up to normal operating temp. Your engine running a little richer when cold is normal but as the temp. of your O2 sensors increases it aids in leaning out your air/fuel mixture. If you desire to correct this your best bet is to have your computer reprogrammed.

 

[CBASS]

Your rear O2s have nothing to do with engine management, they are there to just sniff for cats. The fronts ones are the ones that the engine uses for fuel control.

BTW, how much louder is your off road X-pipe compared to the stock H-pipe?

 

[03-s281]

I can tell I lost some noticeable torque but feels stronger up top.
The sound is worth it. Can't tell about gas mileage.
How can you tell if its running rich?

 

[yamie700]

I installed the x pipe and magnaflows at the same time so I just know it is much louder than stock; but only when you get on it. Just cruising around it is barely louder than stock. I also noticed a little loss of down low torque but the gains from about 3500rpm on are great and more than make up for the loss.