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Ways to get better MPG?

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Old 07-28-2007, 10:45 PM
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Ways to get better MPG?

Ive had my car since 7/7/07 and am looking for ways to get better MPG. I am averaging about 180 - 200mpg. Of course this is going from a full tank and when the gas light turns on.

Just had the leading plugs and coils swapped out at my local Mazda dealer.

Money isnt a problem for the gas, but of course when anyone can save a bit of money here and there it helps.
Old 07-28-2007, 10:53 PM
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Originally Posted by Vasichko
I am averaging about 180 - 200mpg. Of course this is going from a full tank and when the gas light turns on.


over 180 MPG and you want more!!... I'd be happy to get 20 MPG

Seriously, what year is your car, how do you drive, City, Hyw?

No info, no answers possible.

Searching mileage will help.
Old 07-29-2007, 02:22 AM
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05'

City Driving 0 - 90%

I would say I take it to 9k at least once a day only because I dont want carbon build up.

Originally Posted by DarkBrew


over 180 MPG and you want more!!... I'd be happy to get 20 MPG

Seriously, what year is your car, how do you drive, City, Hyw?

No info, no answers possible.

Searching mileage will help.
Old 07-29-2007, 04:08 AM
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18-20 mpg (I'm assuming that's what you mean) for 90% city driving is pretty damn good. Whatever you're doing, keep doing it. There really isn't any practical way to significantly alter your gas mileage. But don't forget to have fun with the car and drive it like it was supposed to be driven every once in a while.
Old 07-29-2007, 06:49 AM
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Actually, if he fills up when the light turns on (which for me is about a 13.5 gal fill-up), then he is actually getting 14mpg. there is a pretty broad range of mileages that people get, and I am not sure you are out of the ordinary.

I do better than that in similar driving, closer to 16mpg at the worst, but I seem to have been blessed. On our spring Adirondack run, I averaged about 3mpg better than everyone else in exactly identical driving conditions, and I had favored power over economy, keeping the car in lower gears than I would on a daily drive.
Old 07-29-2007, 09:58 AM
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Coming back from Reno yesterday I was at 270 miles when I refilled with over a quarter tank left. Turned out to be close to 28 mpg. I discovered the secret to better mileage. Always drive down hill
Old 07-29-2007, 10:11 AM
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6th gear. The more time you spend in that gear the better the MPG.
Old 07-29-2007, 11:43 AM
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I try that. Oh well, maybe exhaust and intake would help a bit?

Originally Posted by expo1
6th gear. The more time you spend in that gear the better the MPG.
Old 07-29-2007, 11:45 AM
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Originally Posted by Vasichko
I try that. Oh well, maybe exhaust and intake would help a bit?
My cat-back seemed to hurt my mileage a bit but it might be because I'm listening to the engine more...
Old 07-29-2007, 11:52 AM
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the 8 loves the freeways so try to take them if the situation allows.

been hitting about 20-21 mpg for the last two tanks, 75% highway drving. or about 8.5 - 9.0 km/l as google will have it.

oh yeah, a light foot helps too, but that's not possible all the time!
Old 07-29-2007, 03:48 PM
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^I agree. Highway driving is when the 8 gets wayyy better mileage. For me at least.

I notice when I troll in the city I get around 210 a tank. On the freeways I can get over 300. I made a trip a month ago to Vegas and got over 330 to a tank.
Old 07-29-2007, 04:07 PM
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A clean engine is an efficient engine.

Carbon/Sludge/Varnish and other gunk on Injectors, Plugs, Rotors, Intake ports, Exhaust ports, and Catalyst all contribute to a less efficient engine - and the rotary, due to it's rich fuel mixtures and oil injection, generate lots of it.

Try this.

Last edited by Jax_RX8; 05-29-2008 at 03:44 PM.
Old 07-29-2007, 04:12 PM
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i set cruise to 65 n i redline once everytime i drive n i still get about 310 miles to the tank, mostly hwy driving
Old 07-29-2007, 04:12 PM
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at what point should I ask my delaer to look at my car? I currently drive 99% city, back and forth to work. The fastest I tae it is 45mph or so. and the commute only takes about 10 minutes a day each way... i am currently only getting 160 - 180 miles before I need to fill up... Closest I can figure I am around 12 MPG. Once a week or so i do take it out on the highway and wind it out, just cause its fun.

I have only had this car for 3 weeks and am looking forward to my first long trip, but I want to know if I should ask the dealer to look at it now, or wait till a nice long trip to see what happens....
Old 07-29-2007, 04:34 PM
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Originally Posted by ModestoRX8
at what point should I ask my delaer to look at my car? I currently drive 99% city, back and forth to work. The fastest I tae it is 45mph or so. and the commute only takes about 10 minutes a day each way... i am currently only getting 160 - 180 miles before I need to fill up... Closest I can figure I am around 12 MPG. Once a week or so i do take it out on the highway and wind it out, just cause its fun.

I have only had this car for 3 weeks and am looking forward to my first long trip, but I want to know if I should ask the dealer to look at it now, or wait till a nice long trip to see what happens....
Extreme City Driving (which is what you are doing) will always get very low mileage - this is normal.

Also, your in "warm-up" mode for most of your driving, contributing to the low MPGs as well.
Old 07-29-2007, 04:36 PM
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Originally Posted by ModestoRX8
and the commute only takes about 10 minutes a day each way...
there is your problem - the motor never really gets warmed up enough to be efficient . You bought the wrong car for this kind of treatment - not only will your fuel consumption be crap but your motor will carbon up very quickly .
Old 07-29-2007, 07:18 PM
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At the 1/4 mark, my last 3 tanks have covered 250miles/400km. Looks set to be the same this time!

Given a full tank I could possibly cover another 150 more!


Last edited by killinghall; 07-29-2007 at 07:24 PM.
Old 07-29-2007, 07:51 PM
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Originally Posted by Brettus
there is your problem - the motor never really gets warmed up enough to be efficient . You bought the wrong car for this kind of treatment - not only will your fuel consumption be crap but your motor will carbon up very quickly .
meh.. my usual commute is only about 7-8 minutes a day and i average 19+
Old 07-31-2007, 04:25 PM
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follow a semi as often as you can, you ll have less drag from the wind. 20 to 40% increase in miles
Old 07-31-2007, 07:07 PM
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Originally Posted by h-khunterkiller
follow a semi as often as you can, you ll have less drag from the wind. 20 to 40% increase in miles
And a well dinged up nose piece with busted oil coolers and AC condenser.
Old 07-31-2007, 07:16 PM
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Originally Posted by Jax_RX8
And a well dinged up nose piece with busted oil coolers and AC condenser.
i said a semi not a cargo truck. they will pick up as much rocks as any car, plus you should have place a grill in front of them by now
Old 07-31-2007, 07:17 PM
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There are a couple of very good "ways to increase MPG" threads available; I recommend you look them up.

In day to day driving, expect 40 miles per quarter-tank mark. That comprises a mix of 5 mph, 25 mph, 45 mph, and 65 mph zones, along with getting stuck in merging traffic on the trip home during rush hour.

During multi-state relocation travel, at 85 mph, expect 60 miles per quarter-tank mark.

"40-60 miles per quarter tank" is a phrase that covers almost all previous and future "I got such and such" mpg responses and quotes. With the following exceptions:

1. The guy whose tach got locked at 9500 and wouldn't go down for some reason.

2. The guy who bought an RX8, but found out it had no motor in it and has to push it around everywhere, much like a shopping cart.

Almost anything you do will land you somewhere between 40-60--the result is already known, the exact number is for you to find out. People keep hoping to get a magic tip that will bring them out at 80, but there's no such thing.

Realistically, you can hope to achieve 16 mpg in day to day driving, with the use of 5 x 35. That is, be in 5th gear by 35 mph. It took me 2 years to learn that, and now you know everything I do about fuel efficient rx8 driving.

Last edited by User24; 07-31-2007 at 07:39 PM.
Old 07-31-2007, 07:24 PM
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trade it in for a Prius ...
Old 07-31-2007, 07:33 PM
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Originally Posted by TeamRX8
trade it in for a Prius ...
That's crazy talk!

I say the best way is to drive downhill only with the wind at your back.

If that doesn't work mount a mast and slap a sail on that bitch.
Old 08-01-2007, 08:50 AM
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I average 20mpg in the city and 22-23mpg on the highway. I run 10-30 Castrol GTX, now have been running FD plugs for 4k miles, a K&N drop in, stock wires (just burned out on me) and almost always get Irving fuel.

I am thinking about going to better wires soon and the improved ignition module to see if that will help any.


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