For some reason I get 17-18 mpg and I have modified my Coupe a bit. I have installed a Popcharger, plenum spacer, high-flow cats, Borla true-dual exhaust and Z-tube.

These mods should add power and if I drive conservatively it should increase my mileage right? I have reset the ECU after each mod.

Does anyone have any ideas as I am starting to get pissed. Do I need to get my AF ratio modified as I have not done any professional ECU tuning?

Thanks for any help you guys can offer.

Jason

 

It seems that all of us are getting the same type of milage. It may help to get your engine tuned to your mods.

 

Could it be that you're a little more Heavy With that Right Foot?

 

My expierence with add ons are that they waste gas. I never heard that they save you gas on mileage. It wouldnt make sense if your car created more hp with saving gas....if you enging creates more hp its going to burn more fuel and faster. Correct me if Im incorrect.

 

I can only speak for my G's gas milage. It's improved with my particular mods -- as long as I don't change my right foot's operating practices. More efficient air/gas flow & combustion = more power = less throttle to do the same speed. Taking full advantage of mods with a heavy right foot = fun = poor gas milage. Catch 22!

 

I would echo DaveO: better breathing = more efficient.

Me behind the wheel = 9 MPG!

 

sorry that doesnt make sense to me?????
Your equation doesnt work out like that in reality
More efficient air/gas flow & combustion=more gas burned=more power
I dont think you can make your car anymore gas efficient than the way you bought it at stock. You can only make your mileage worse with bolt-ons, you are not going to make your mileage better. Maybe you think that vortex fan you stick in your intake, and ground wire, mmmm and a speed chip will get you better hp and mileage too.

 

Can't speak for the G, but when my WRX wagon was fully catless, with a Borla Hush
exhuast and Cobb Accessport at Stage 2 I actually got an improvement of 1mpg.
That was even with more aggressive driving style.

So maybe the G's ECU needs a reflash or something.

 

I'm really sorry my comments didn't make sense to you. They will to many people. By the way, you forgot to list the fuel magnetizer with my other mods.

 

Are people really that stupid? They think that greater efficiency = lower power? OR more fuel consumption = less efficiency.

God poeple are dumb!

 

You're thinking about it wrong, bubba. Additional N/A mods (spacers, exhaust, headers, cats, intakes, etc) usually make more power by creating better breathing for the engine, which means that the engine is better at taking in and using the air to create power, so what used to take 75% throttle to attain a certain power level may now take only a 70% throttle to attain that power level since the engine breathes more efficiently.

As long as you don't change the driving style and use more of that new-found power... then you're gas mileage should improve - because your engine will be better (more efficient) at creating that power.

Of course, forced induction systems don't really apply. Where a typical N/A engine just has to use it's power to spin the crankshaft, pistons and valvetrain... a F/A setup also has to either spin a supercharger (loss at the crankshaft) or turbos (exhaust backpressure). Also, fuel may need to be increased to prevent detonation...

For instance, I put a Gibson exhaust on my V8 Grand Cherokee several years ago, and it increased HP by 17 and Torque by 28 - very noticeable - because the stock exhaust was somewhat restrictive. My MPG also increased by about 1-2 in the process, especially when towing my boat.

 

mileage varies greatly depending on driving style and average town vs freeway driving.
It has been talked about here endlessly.

Breathing mods overall slightly improved my mileage.
My average freeway lately is 22 - 23MPG ( i have been pushing it more lately) but when I drive nice doing 24 or 25 is no problem.

Around town, 16 - 18 is the norm, but if you thump it a bit it is easy to be at 14 real fast.