bestest/cheapest way to get better mpg?

durps

Member
just got a p5 and i cant complain about the mpg i'm getting, but getting a better mpg rating wouldnt hurt the wallet in the long run.
anyone know the best things to do to a p5 to get better mpg? i mean part- wise.
thanks
 
replace filters on a regular interval?? tune ups at regular intervals. Usually just regular maintenance keeps the car in an optimal range for mpg. Parts wise are you talking about OEM or aftermarket?

By the way, welcome to the forums. There is a lot of info on here and a lot of good people on here that can help you out with anything with your car. Post your location to your profile, you may have someone on here near you.
 
thanks man, appreciate it.
and aftermarket wise. i wanna buy some goodies too but don't know where to start. so far only thing im upgrading is a cold air intake.
 
the best way is to control your foot. if you consistently just keep light pressure on the pedal, you'll maximize your fuel mpg as your car is now. the further you push the pedal, the more gas your going to use. but what fun would that be?

in these cars you should be able to floor it all the time and not have many complaints. we have a yukon xl and it's not too bad on gas, but its a big differance filling up an $85 tank and a $30 tank...somthing to think about
 
hey durps, you running a man or auto? Seems the P5 autos really take a mileage hit. But yeah, gotta keep the revs down and stay out of the throttle. Keep the tire pressure up. All the basic stuff. Header & exhaust can help a little.
 
Does the P5 display have a mode where it displays the MPG every couple of seconds? If so, play around to see what eats the most gas. When I'm bored at times I'll play a game of maximizing the mileage on the highway. I found by allowing the speed to fluctuate by 5 to 10 mph, I can keep the MPG above 30 (Mazda 3, 2.5L Hatch) going up the hills and above 40 much of the time by running it like a trucker. Speed up on the downhill and slow down on the up hill. I think the cruise controls should have a selectable fuel savings mode which would do the same. There are other techniques some have experimented with like drafting behind trucks or alternating flooring it and idling it but they can be dangerous if not annoying to you and other drivers. Some of them are more beneficial with hybrids which can start and stop their engines while the car is running as a normal part of fuel savings.
 
TEN P5 gas saving principals: (attention)

1.) Restraint on gas for manual and keep the rpms low / lead foot for autos (need to get it tourth gear and pass 45 mph for best mileage).
2.) Try not to go over much from 45 as mpg drops the higher you go in speed.
3.) Do not drive with windows open
4.) Coast to a stop light and try to not coming to a complete stop
5.) Remove cross bars and put caps on
6.) Keep care maintenance up (tire psi and regular service)
7.) If you can find it, gas without E10
8.) Do not run AC unless you have a UDP
9.) Do not run heavier than stock wheels
10.) Remove unnecessary weight from car.

BEST MPG mods for P5: (nana)(drive2)
Header - removes weight and increases hp
cai/filter - increases hp
midpipe - increase hp
front motor mount - reduces wasted energy on engine movement
remove VTCS - increase hp
piggy back ECU system - allows you to tune car so no fuel is wasted
exhaust - increase hp
UDP - increases hp and removes a majority of power hit when using AC
springs - lowers car thus giving better aero
good wax job - gives better aero to car
 
Keep ALL of your tires at 32-34 psi cold (and check regularly), drive lightly, do tune-ups/oil changes in 5000k mile intervals, and use 93 octane.
 
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I always experienced 1-2 MPG more when using 93 octane.

Let's see if it's actually worth it (play along at home, substituting the values for ones that apply to you) :)

Code:
price_regular = 2.79 ($/gal)
price_premium = 2.97 ($/gal)
mpg_regular   = 29 (mi/gal)
mpg_premium   = 31 (mi/gal)

price_per_mile_regular = price_regular / mpg_regular = 2.79/29 = 0.0962 ($/mi)
price_per_mile_premium = price_premium / mpg_premium = 2.97/31 = 0.0958 ($/mi)

price_difference = price_per_mile_regular - price_per_mile_premium
                 = 0.0962 - 0.0958 = 0.0004 ($/mi)

If the number you end up with is positive (like in my example), you are indeed saving money (4 one hundredths of a cent per mile in this case). If it is negative, which I suspect will be the case in the real world, then you're just pissing your money away.

For these equations to work, the initial variables must be correct, I selected numbers that illustrate the best case scenario (good gas mileage, and a 2mpg increase with the premium gas). If we can get some real-world data about the mpg difference between regular and premium gas we could determine for certain whether or not it is cost-effective.

I stand by my initial assumption: using premium gas in a P5 is a waste of money (deadhorse
 
OK I'll raise the question of the long-reach ZFR5F-11 NGK spark plugs. I have never run these, but many on here claim that performance/mileage can increase?
 
Do not waste your money on long reach spark plugs. I tried them and did not notice barely anything. They smooth out the way the car runs a bit maybe, but it will not make any huge noticeable change for the money. I doubt it will give you 0.5 mpg if that. I would only get the NGK copper spark plugs (OEM) if yours are needing replaced. DO NOT USE BOSCH, it will kill your car.

Matt is getting 2-3mpg more on Premium than regular because he has a MP3 ecu (not stock P5) which is tuned for premium. So since he has colder spark plugs than stock because of the timing advance, if he runs regular gas instead of premium the spark can not burn all the gas as efficient and runs rich.

Matt has good advice on psi and service. I can tell when I am past the oil's life because my mpg drops a few. The psi should be 32 cold, but you can usually (depending on tire) put 34-35 cold psi in the tire for better mpg. The down side is less traction and less even wear on the tire.

Gas a different pumps might have less Ethanol and thus you will get better mpg. I used to go to Royal Farms just because of this!
 
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trucks hate this, but wind drafting? lol j/k

but I hear filling up at night also saves you money...I guess less gas is evaporated while filling up.

Check everything everyone has already stated.
and o2 sensor.
 
Actually it because the gas is cooler and thus more gas molecules per gallon then when hot and expanded; Good point none the less.
 
Let's see if it's actually worth it

Code:
price_regular = 2.79 ($/gal)
price_premium = 2.97 ($/gal)
mpg_regular   = 29 (mi/gal)
mpg_premium   = 31 (mi/gal)

price_per_mile_regular = price_regular / mpg_regular = 2.79/29 = 0.0962 ($/mi)
price_per_mile_premium = price_premium / mpg_premium = 2.97/31 = 0.0958 ($/mi)

price_difference = price_per_mile_regular - price_per_mile_premium
                 = 0.0962 - 0.0958 = 0.0004 ($/mi)


I stand by my initial assumption: using premium gas in a P5 is a waste of money (deadhorse

...You stand by your assumption, yet your equation proved you wrong... I always got better mileage on premium as well. Even before getting the MP3 ECU upgrade.
 
...You stand by your assumption, yet your equation proved you wrong...

I stand by my assumption because of the 2mpg increase assumption I made in the calculations (which I believe is incorrect). And if anything, my calculations show that you really don't save any money by using premium fuel (you'd save a big 40 cents over 1000 miles).

Anyway, the best way to test this would be if someone was driving a couple thousand kilometers (road trip!). Throughout the trip different fuels can be tested without the environmental factors changing too much (and with relatively constant engine load/speed).
 
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