MPG gain with bolt on modifications
 

Before the flaming starts yes I searched and yes I know this has been discussed before, I just wanted some different and up to date opinions. I was wondering if any of you guys have noticed any mpg gain with bolt ons such as intakes and cat-backs? I was doing the math earlier and with only a 2 mpg gain these mode would pay for themselves in no time at all. I could care less about 5 hp. But a mpg from each would make my day. I know at first after mods one is probably a bit of a lead foot, but after that initial break in, did anyone notice any gains? Any experiences?
Thanks
-Matt

went from 180-190miles per tank with exhaust to 220-225miles per tank after installing hi-flow cat...ummm but could be caused becuase of the re-flashes..unsure....now have intake,hi flow, and catback..miles stay at 220-230miles per tank

A lot of people with the revi intake have reported gains. You can get an Interceptor-X or emanage gold and lean out the top end, but they cost more and top end improvements won't help you if you're driving conservatively, trying to get good mileage.

has anyone noticed any gain with ignition wires? I'm thinking of purchasing these, a catback, and and intake.

i didnt notice any gains in mpg with my intake, duct, and exhaust.... but i love them!!!

The more free flowing your exhaust system is, the better your mpg will be since you are leaning your car out. I've seen much better gas mileage since i've had my bolt ons installed.

i got my ignition wires way early on so i dont know if it helped or not...

I'm guessing you must drive 40k miles a year or think several years is no time at all -shrug-

12,000 miles / 20 mpg * $3/gal = $1,800
12,000 mies / 22 mpg * $3/gal = $1,636


Changing your driving habits will effect your fuel milage much more then any mods out there will (which is basically 0)... and its free

i have the AEM CAI n the greddy sp2 n they havent had any effect on my mileage, still get about 260-270 a tank with mixed driving.

HAHA, if premium was $3 a gallon here I would be a happy man. I'm guessing that how many mpg you get before the mods will have an effect on it, which is why some people experience gains and others dont. Those that already get 19mpg probably arent going to gain much out of it, while those that are stuck around 14 mpg might. As far as driving habits go, I've tried it all, driving like and old woman, wood block under the gas pedal, and even the famous "shift and 4500 rpms, its the optimum shift point" idea. I still cant seem to break 16 mpg. Granted I live in a city and do mostly stop and go driving. That being said, this is cleaning me out.

I have the OEM stock air box with a hi flow aFe drop in filter, with VFAD and internal air box baffles removed. I have alos performed the throttle body by-pass mod (can only but help)......cost of these mods = ~mainly $50 for filter.

I just filled up at 260 miles....and that is sitting in rush hour traffic to and from work.

I have stock exhaust system and an aluminum flywheel.

i would think changing your wheel size and changing to like 410 gears would have the most positive effect on your mpg

easiest quickest way to increase mpg is to increase your tire pressure... that was a trick i used in my honda hx.

To what psi?

I have the MS Sport dual can exhaust, AEM Intake, Ground wires, and I definitely see an improvement in my gas mileage, and I dirve pretty hard! gains are minimal as we all know, and my gas mileage is around 16.2 roughly.... Im happy with my bolt ons and I don't plan going FI anytime soon, maybe when the warranty is up, I'll go with Pettit or Hymee's SC system!

it's funny how most post in this forum now, begins with sentences like "before you flame me I searched"...

i've heard the rb intake increases mpg, not sure if thats true. But like mike said the more free flowing you exhaust system is or better tune would equal more mpg.

must be hard to get this past your wife since youre looking for support here :)

try .. not only it pays for itself but it also extends the life of the engine

Get a Fidanza flywheel, Turbo XS exhaust, some midpipe, Racing beat intake w/ duct, AFE short shifter, stickier tires and lighter rims, interceptor and a base RX8....and you should be getting pretty darn quick

lol i thought he asked for Mpg Mods.. lol not speed mods ??
question though, since we are on the subject... anyone run the 1/4 with the basic aftermarket flywheel, exhaust, and intake?
(funny.. most cars the usuall is the Intake/header/exhaust..for us its intake/Flywheel/exhaust)

when everyone reads my this theyre going to think im nuts.
With my car, the "dont drive with a lead foot and you'll get the 18 your supposed to" doesnt apply. I have the MS CAI. Didn't help. That's all I've done so far.
But! If i shift uner 4000 RPMs all the time, with a redline a day I get like 16.2-16.4 constantly. Shifting at 6000-6500 through the gears gets me about 17.1-17.5.
But yes...intakes claim to save you a little bit gas mileage if you drive it unchanged and nicely...I have yet to see it.

Thats because there is only one header option out there for us that isn't over $1k, and even that one doesn't even have the airpump connection.

I've used that couple of times on my wife...

Good thing is she understands my quest for power as well as the technical bits up to ignition timing.... ;)

I am trying the tire pressure thing.
The door plate shows 32, but the sidewalls show 50, so I put in 44.
Ride is a little harder, handling is just as good or better, and I would like to say the the MPG had gone up, but I also ran 89 octane in the last 2 tanks - for cost.

[QUOTE]when everyone reads my this theyre going to think im nuts.
With my car, the "dont drive with a lead foot and you'll get the 18 your supposed to" doesnt apply. I have the MS CAI. Didn't help. That's all I've done so far.
But! If i shift uner 4000 RPMs all the time, with a redline a day I get like 16.2-16.4 constantly. Shifting at 6000-6500 through the gears gets me about 17.1-17.5.
But yes...intakes claim to save you a little bit gas mileage if you drive it unchanged and nicely...I have yet to see it.
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is that possible to get better gasmilage at higher rpms? im not possitive but i think thats happend before.. when i shifted at higher rpms i got better mpg...

is this whole lower rpms thing better for gas true? i was wondering cuz i partially taught myself how to drive stick... since i though it was best to be at lower rpms for mpg if im crusing at like 35 id have it in 5th... is that bad?

well its not really in normal cars... buyt in the 8 lows rpms run rich, and high rpms.. are.. well.. high rpms, i think mazda recommends shifting between 5-6k...
i usually shift between 4.5-5k