now i realize this has probably been discussed countless times however hopefully everyone still has some patience!

i have an 88 n/a thats had the 60k tune up:
all new fluids
plugs and wires
fuel filter, oil filter, air filter
new pulsation dampener (gave out couple weeks ago)
new o2 sensor
as well its just a drop in k&n but still...and i have dynomax mufflers with no cat (gotta love BC haha)

i haven't got a chance to check the tps but its running pretty good so im not too worried about it

what i'd really like to know is other than a header what other options do i have to get some better mileage here, cuz i don't see gas prices getting any lower in the future

thanx guys

 

Drive it like your Grandma stole it.

 

well normally i rarely take it over 3500....any other suggestions?

 

Fuel computer.

Weight reduction.

Check the TPS. It takes about 3 seconds.

Engine brake. It cuts fuel to the rear rotor.

Shift very low. I shift around 2500 in town.

Don't accelerate more than you have to. If you're at a red light and there's another one 100 yards away, there's no reason to go fast. Just take it easy and find a decent cruising speed. Who cares if the people around you hate you for it.

 

What kind of milage are you getting?

 

I'm getting 13.5mpg/city as of the last tank, and i've done everything you have except the transmission fluid and pulsation dampner. '87 GXL shifting at 2500 most of the time.

 

That's not TERRIBLY bad for city driving. It could be better...

 

I am not sure on the gearing on the FCs but it also helps jumping gears.

As in go from 2 to 4th gear. 3rd is an accelaration gear and is not needed for normal driving. saves lots of gas.
Also stay in 1st gear only when rolling and go to right into 2nd. as in dont even pass the signal in 1st gear, you should already be in 2nd.
Inflate the tires abit over usual. The car has it easier and also you can go into neutral before stop lights sooner as an example.
dont use the AC too much, if you have one.
Dont open the windows too much.
dont use too many electronic devices at once, is the basic term i guess haha.
check your grounding.

thats all i can think of right now. i hope it helps.

 

jumping gears does help. windows up/down dosnt make too big a difference (not that ive noticed) too many electricals also dont make much difference. My milage dosnt change at all with say everything off vs lights and sterio all the way up.


13.5mpg for an NA is not good. maybe for a t2... i dunno, i get right around 19-22mpg in city if im not all up on it. i cruise the freeway around 90, and get about the same.

 

get an SAFC and learn to tune it

 

Yes. That'd prolly be the most effective way.

 

put the windows, all the electrical stuff together and then it'll make a difference.
basically you are adding up, haha.

 

The issue I've been posting about lately is the fuel pressure.
If manifold vacuum is not getting to the FPR, it will go way rich ar idle, low, & part throttle.
And, on turbos, it will go lean under boost.

A cheap narrow band AFR gauge is no help for power tuning, but it can be useful for spotting problems with the TPS & the O2 sensor.

When you decelerate using engine braking with the throttle closed, fuel is cut completely, so you're just pumping air.
There is a very narrow band decelerating at 2-5% throttle where you get just a single rotor fuel cut.
That's why the TPS setting is important.

I think the shift up light on the S4's comes on at 2500?

 

might as well as loose a couple pounds while you're at it, that'll save you some gas won't it.

The shift light's bit iffy, I've seen it come on at 2,000 and sometimes it won't come till like 3,000.

 

I'm not sure the minimum rpm, but it depends on throttle percentage.

 

the best way to get alittle more mpg out of your rotary is to remove your antire intake and clean it, as in polishing all the ports and port matching all the pieces. and while all of its apart send your injectors out to get cleaned and flow tested. only costs about 150$ including new gaskets. i was getting about 13-15mpg driving like grandma then i did this and now i get about 18-20mpg and i drive my fc like i stole it. it only is going to work with a good freeflowing intake and exhaust though.

 

Just go to a local diesel shop and have them do it.

 

We see these threads pop up very often and i really would like to know how much gas mileage are you gaining by utilizing all of these methods? It can't be much.

Is it actually worth it?

 

Who doesn't want better gas mileage?

If it's already around 18... not as much use.
If it's around 8... a hell of a lot of use.

The lower the mileage, the larger the problem(s). So... find it and fix it.

 

Your talking about a car that never really had great gas mileage, and I was asking how much of a gain in mileage do you really gain? 1, 2, 5, 8.....

 

Well if you get everything running up to standards, you should see 20+ mpg. Like I said, depends on what you're at now.

 

i get 17 in town regardless and 24 on the hwy

 

Nice. I get about 18 with mixed highway/town.

 

just FYI, ive noticed a 1 mpg difference between 5/6th ports wired open and closed. I average 21 mpg with ports wired open, no emissions, full exhaust, shifting at shift light, on premix

 

What kind of driving are you doing? How did you measure this? Over what period of time?