How I made 22-25 mpg in my RX-8
 

Step 1: Buy an AccessPort from MazdaManiac

Step 2: Flash your car with the supplied map.

Step 3: Enjoy!


Both before and after I was turbocharged, I could made up to 18-19 mpg if I was not driving very fast and used 6th gear without a lot of throttle.

Regular mixed driving yielded 14-16 mpg.


The interesting thing is, unless I let up all the way off the throttle, using the scangauge2 for instant mpg numbers, there was really no way to crack into the 20 mpg numbers even on flat ground.

With MazdaManiac's maps (And I wonder if it's the OEM cat extending life "feature" that is the root cause for consumption) leaning out the fuel at cruise, I can easily hit 22, and can even go to 29 mpg at some points without letting off the throttle.


As we all know, each of our cars are slightly different. With the difference between 17 and 19 mpg resulting from very slight changes in throttle position, I think that the small variations in injector sizes, engine, etc is accounting for why some can't go over 16 mpg while others are in the low 20's. Tweaking out the fuel mapping is leveling the playing field :)

I've been a bit cautious about the AP, I haven't seen much information on it's long term "side effects". If I drink a can of monster energy every day, yeah, my heart beats faster and I have more energy, but I wonder, if I drink a can a day for 30 years, is it going to shorten the life of my heart?

Correct me if I'm wrong.

Also I wonder if it's good for your FI engine to be running a map leaner than the original one designed for an NA...? Seems VERY lean to me.

You forget that for cruising the FI rx-8 runs the same as NA. Only when the turbo pushes more air does it inject more fuel... so running at 15 AFR on the highway isn't a big deal and I have no cat that would get fried due to heat.

I figured your turbo kicked in sooner than that. At what RPM do you make significant boost? When I thought "Cruise" I thought around 60mph in 6th which is around 3.2k in my car.

I assume your map compensates for when you put your foot down, right? Yeah, it must.

boost is load based, not rpm based. I can go to high rpm without going into boost.

I can make 12 psi at 3,200 rpm if I stomp on it.

So...... probably a bad idea to follow your suggestion for folks w/ OEM cat?

There are gains to be had. Jeff can tweak out the maps anyway you want.

But don't expect 100,000 mile life on your cat if you lean it out.

wont mater in 30 years. electric cars will rule.. caribou must die.

beers:beer:

Hell, I'm already getting 25+ on the highway! Wonder how much better it will get once the AP!!!

you might get nothing. try it and see.

right now in light throttle cruising the car quietly slips into open loop and dumps fuel to cool down the cat. I suppose everyone would gain from stopping it or lowering the amount of fuel dumped, but I can also see diminishing gains - in NA form you're hard pressed to make more than 220 whp, regardless of fuel/timing settings. So maybe the renesis might be hard pressed to do better than 25 mpg.

220whp is better than what most of us NA guys are making anyways...I'll take what I can get! Atleast until I can get the dough together to go FI...also I do agree with you mysql about the mpg's. I'm not complaining about what I get, I'm more than happy after seeing how so many here don't get anywhere near that in their cars.

How come Racing Beat was not able to get any better fuel economy with their flash??? They were not only going for performance but said they were also trying to improve fuel economy but could not.

Because they didn't have MazdaManiac work on the development with them! HAHA!

Seriously? I mean RB is not exactly a bunch of newbs when it comes to rotaries.

rb also has a one sized fits all flash. Not true of what MM is doing.

So is there a trade-off, eg, better mpg means less than optimal hp?

Oh I know they're not but a blanket flash will never yield the same results for everyone. MM has gone above and beyond with the AP.

not at all. less fuel gains power too (leaner afr). But we're talking about the cat-saving cruising stuff, not WOT.

Still don't understand why RB wouldn't have gotten better mpg.

if MM was limited to shipping only one map for everyone, his results would be similar to RB's too. Since that isn't the case, there is no need for artificial safeguards for random cars that might not take well to the modifications. e.g; no need to have an extra point of AFR for some vehicles that might have fuel injectors under the rated size.

Thanks, I need to do some more reading.

I think I see the one thread I'll have to show the gf to justify buying the AP :lol: Anything to get me out of the 16mpg wall of 50/50 driving and I'll be a happy camper. Only seen 21mpg on one tank and that was on cruise doing 65mph about 2 car lenghts behind a semi the entire trip for a hour.

The way MM has been customising his maps for EVERYONE just astounds me. As others have stated he must be a masocist of some sort, but I wont complain once I buy one hehe.

funny,

on the way up to savanah i got 22.7 mpg. in savannah i got 8.9 mpg. on the way home it is looking like i might be in the 24 mpg range. ;)

btw, met rob and adam.. and bought a hat..

jason, what are you getting mpg with? have you done it the old way? fill tank get out calculator.

beers :beer:

HAHA! Good for you Scott! They are a great bunch of guys...looking forward to getting on the road this week and head to Lime Rock!!!