austinsFD

i have a 1994 fd3s and i was wondering if i lowered the fuel inj. CCs in the PFC would i get better gas milage or would it just screw up my engine and turbos?

Hyperite

lowering the fuel injector size in the computer would cause it to dump MORE fuel, since it think you have smaller injectors and has to open them wider. Anyway, this isn't stuff you want to do regardless, in either direction. Proper tuning will give you the best compromise between power and fuel efficiency. I say don't mess with it.

austinsFD

thanks hyperite

mad_7tist

550cc and 850cc injectors not exactly fuel efficent. fast though.

what kind of mileage are any single guys with upgraded injectors getting?

ijneb

better gasmilage?
www.autotrader.com search for honda.
get an old, ugly beat up one if thats all your budget will allow.

You'll be glad you did.

rynberg

Oh my god. That's all I have to say about your PFC idea. Do yourself a favor -- DON'T CHANGE ANY SETTINGS ON THE PFC.

You want fuel efficiency, buy a Civic.

austinsFD

why are some rotary guys such a**holes when people ask questions "rynberg" im sure you had questions when you got interested in the rotary engine i guess people gave you alot of sh*t when you started in this fourm!

austinsFD

why are some rotary guys such a**holes when people ask questions "rynberg" im sure you had questions when you got interested in the rotary engine i guess people gave you alot of sh*t when you started in this fourm!

Broken09

iTrader: (1)

I think it's the fact that you bought a sports car and now you want better gas mileage. It's just one of those things that if you buy a car like this you have to be aware of the fact your gas mileage will suck. You pay to play. I'm not trying to be an ******* here just stating the facts.
-Nic

pomanferrari

iTrader: (1)

Rynberg isn't an a$$hole telling you not to mess with the PFC settings. And Rynberg educates himself before asking questions. You obviously have no clue. Nor did you bother to educate yourself.

You might as well ask if you can get better gas mileage if you change the "cc" setting to zero. That way, you'll never have to pay for gas.

Sesshoumaru

iTrader: (1)

there are other ways to squeze gas milage out of a rotary safely

I'm in the 20's all day with my TII with a street port and no 5th gear senor.

Change your 02
Reduce backpressure
Increase intake
High compression numbers help
clean injectors

not sure if the fd's do this or not - but in fifth gear it retards timing and fuel for FC's.

I'm gonna shoot for about 22-25 on my FD

XSTransAm

not to discourage you, but i get about 14 on my FD... I dont think you can get 22-25

sorry

ijneb

Maybe he can... going down the side of a mountain with the engine off

scotty305

iTrader: (2)

A cheap, effective way to prevent detonation is to run rich. If you choose to lean out the fuel mixture, be aware that you run a high risk of damage to your motor.

If you want better mileage for some kind of endurance racing or something, look into decreasing the weight of the car, lowering the drag coefficient, or maybe lowering the boost somehow (but I'm not too familiar with boost control).


If you absolutely feel you must run lean, buy a J&S Safeguard so you can curb the detonation that you're very likely to run into. If you think a full tank of premium is expensive, look into the price of a rebuild...


-s-

Kevin T. Wyum

Hrmm? I got 25mpg on the transit sections (read lots of highway time) of the One Lap. I don't think I really ever went past 45% throttle position doing that though.

Kevin T. Wyum

rynberg

Why do so many ignorant kids think they can afford to properly own this car?

No, people didn't give me ****, because I didn't ask a bunch of questions without doing a little (or a lot) of research first.

Please explain how I was an *******? You obviously have absolutely no clue about engine management systems or how a fuel injected car works. That's not an insult, it's just an observation. Since that's the case, it would be best not to change any settings on the PFC, as you could blow the motor.

As far as my comment regarding gas mileage, read my first reply above. This is a hard core sports car. If you can't afford to put gas in it, sell it and move on to something else more practical. For some reason, your generation seems to think they have to have the best of everything RIGHT NOW. I waited until I was in a position to properly afford a car like this, it's obvious that a large majority of the current FD owners don't.

jimlab

Because they don't look any farther than the purchase price.

If a few extra gallons of gas a week are causing you any financial hardship, you bought the wrong ******* car.

scotty305

iTrader: (2)

AustinsFD kinda sorta almost brings up a good point though; I've noticed that lots of old-school rx7club members are pretty vicious when it comes to answering dumb questions. On the Subaru forums I used to frequent, when someone asked a question that was deemed ignorant or noobish, the attitude was a little more laid-back compared to this forum. We would still mess with them, but in a more friendly joking manner, not as blunt and confrontational.

I guess my point is that if you discourage the ignorant person because you deem that his question is dumb, he's likely to stop seeking knowledge, and the end result is one more mistreated RX7.

-s-

AREITU

Because they've been around long enough to where they've heard the questions a million times. Subarus weren't popular until Subaru brought the WRX over so everything is still all good. Check back in a few years then you'll get a few pessimists. I get vicious at newbie questions because it only takes a simple click of the FAQ or five minutes with google.com to figure out what they're asking...

Sesshoumaru

iTrader: (1)

was that really necessary?

it's been done

https://www.rx7club.com/showthread.p...hreadid=186070

this is same thing you see in the 2nd gens too

people range from 10mpg to 20mpg and up

It has to do with how you drive and what is hwy and street. Other half is engine condition/mods

I think 20's are a realistic and obtainable goal.

Stock hwy is about 20 if i remember and with a opening up the intake/exhaust i think i can get 1-2 more mpg.

Hyperite

I get 22 in 5th when it's hot out, A/C off, rarely boosting. You'll get better gas mileage in warmer temperatures, but with the less-power tradeoff. My first tank of the season, I got 12.2 MPG (but it was a fun ride ). I have the feeling w/ the high gas prices, this'll be an expensive summer.

Everybody posting about increased mileage with mods, it doesn't exactly work like that. Decreasing backpressure will require more fuel. Don't believe me? Go drive with a cat for a tank, then swap in a midpipe. Watch the fuel level drop when you floor it. It's almost visible!

Basically, don't expect anything better than a max of 17. If you get it, congrats, if not, too bad. It's a 10 year old car with a thermally inefficient engine. But that's why we love them

rex u.k

You US people should never complain about fuel consumption, the pittance you pay for it.

P'cola FD

Let me jump in here for a second. With a pettit unlimited ecu, intake, dp, mp, cb, and ported intake ports, I consistently saw 18mpg in the city (when not beating on the car), and 23-24 on long road trips. It is not hard to get better mileage, just make sure the car is running properly, and keep your foot out of it.

Another thing, I know it seems that people can be total ******** for jumping down someone's throat just for asking a simple question, but what most people don't understand is that a lot of us have been on here for many years. It seems that many questions get asked in threads more than once a day. Other questions only get asked every few months. Either way, they have probably been discussed way beyond thoroughly in more than one thread. Senior members get upset because all a person had to do was go to "search" and type in "fuel efficiency" or "fuel consumption" and had at least one thread where this was previously discussed.

BTW, even with a standalone, and many mods you can still get "decent" mileage. The big thing is using a wideband, and tuning the light load areas to stoich, and setting up a closed loop system.

scotty305

iTrader: (2)

A better /more accessible FAQ system would help , years ago when I was into computer hardware/overclocking, I helped revamp one of the FAQ's at www.hardocp.com . When noobs would come asking stupid questions, it was possible to just reply "read FAQ, it's in there!" and lock the thread.


Maybe someday when I've got enough rotary knowlege I'll try to do something like that around here.

-s-

adam c

iTrader: (2)

If you open up the intake and exhaust restrictions, you will get better gas mileage at minimal throttle pressure. The system doesn't have to work as hard to move the car. The problem is that most of us don't drive our cars like that. Now that we have the capability to use more fuel, we do.

Back to the original question. You didn't buy this car because it gets good gas mileage. It gets lousy gas mileage. Unless you drive it like an old lady, there isn't anything you can do about it.

At least you can have a big smile on your face when you are not at the gas pump