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Hopefully getting 30 mpg out of my coupe


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After my headgasket incident (thread to come soon), I'm going to turn my coupe into a commuter (goal: 30 mpg), and I've got a few questions.

1. I'm definitely leaving it spfi, but I'm wondering, which engine gets better mileage, the ea81 or ea82?

2. I've got 155/80/r13's on it, should I leave those on there? My thinking is, less surface area touching the ground, less resistance, better mileage.

3. I'm taking the power steering out of it, would a manual rack and pinion out of an 85 wagon bolt right in?

4. Not really a question, but I'm hoping to get a 5-speed sometime soon, and I know it'll help with my mileage a lot more than the 3at that's in it :lol:

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excuse my forgetfulness....is it FWD?? Cause if its FWD you will have no problem...dont forget my old FWD EA82 wagon would get 40mpg on the highway....32+ city..that guage never moved.

 

:eek: Bucky got 40? Oh, that would be nice if I could get that. And yes, its fwd. Damn, I'd like to see those kind of numbers :banana:

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:eek: Bucky got 40? Oh, that would be nice if I could get that. And yes, its fwd. Damn, I'd like to see those kind of numbers :banana:

 

Yup Buckster was even known to get 42 on a long haul highway run at around 73 mph...Here is the scoop...FWD 5 spd...keep it tuned well...I was running 175/70 R13s on him..hold up..175 front and he had 185 rears for awhile cause they were free tires...

You are going to have alittle trouble until you loose the 3AT...once that is gone and a 5 spd in it place you will have noticable difference..not just in gas mileage either.

For now..put a new 02 sensor in..keep it good and tuned make sure you have a clean air filter in it...make sure your wheel bearings are good and you have good tires at the right pressure..and you should be good to go.

Like I mentioned..your gas mileage anchor is that 3AT

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Yup Buckster was even known to get 42 on a long haul highway run at around 73 mph...Here is the scoop...FWD 5 spd...keep it tuned well...I was running 175/70 R13s on him..hold up..175 front and he had 185 rears for awhile cause they were free tires...

You are going to have alittle trouble until you loose the 3AT...once that is gone and a 5 spd in it place you will have noticable difference..not just in gas mileage either.

For now..put a new 02 sensor in..keep it good and tuned make sure you have a clean air filter in it...make sure your wheel bearings are good and you have good tires at the right pressure..and you should be good to go.

Like I mentioned..your gas mileage anchor is that 3AT

 

I always thought that slightly bigger tires would give you a little better mileage, since the engine has to turn less rpm's to go the same speed. It looks like I might leave the p/s and the 3at in the coupe for now until I get the wagon roadworthy, its got pushbutton 4wd, and I'd rather drive a 4wd in the snow.

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dont worry about the power steering.. the power steering pump only puts a drag on the engine when the steering wheel is BEING TURNED... in other words, drive straight, no drain, approach a turn, and while the wheel is turning the steering pump saps a little energy, once the wheel achieves its maximum turn, no more power drain, the return back to straight is achieved mostly by the inertia of the car and proper caster setup on the front wheels.

 

In other words, the oil pump is about 50 times more of a power drain than your power steering pump. So is the water pump. So is the alternator. Heck, when you figure the electrical drain, and thus the physical load the alternator has to put on the engine to compensate, your stereo is probably almost as much power drain as your power steering pump.

 

tires:

 

wider tires do in fact increase rolling resistance.... but man, I switched my GL10 to 185-70s and never looked back. The increase in cross-wind stability i got in the car alone was more than worth any mileage penalty i paid, and any penalty was minimal. TALLER tires will give you an increase in cruising fuel economy, because they decrease the gear ratio and you achieve more real MPH per RPM than you would with shorter tires... but the tradeoff here is that you lose acceleration, which IMHO is a very very precious commodity in 80s subaru land, not to be given away lightly. (Then again, I did land in my 3at soobie after driving a 280Z for five years, so maybe I am speed-spoiled :-p )

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I've heard many times of auto cars giving 28mpg. I can't speak to that, never having owned one, though my Legacy turbo auto gives 32mpg highway.

With a front wheel drive DL 5 speed I used to see (before retirement) 45mpg, up hill, down hill, empty, loaded. With my 4WD 5 speed Loyale (in front wheel drive mode) on it's maiden voyage (home) of 1000+ miles I saw 43mpg.

 

All the changes you mention, excepting swapping out of the automatic, mean little if you do not drive for mileage. Your driving style is what will give you the maximum mileage.

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I would swap the 155's for some 175/70's myself. The 155's sound like to small of a tire to me for a commuter. Maybe ok for a rally car, but to get MPG's up, you'll want a taller tire and 175's should be in the "stock tire" range.

 

Carbed (weber) EA-82 in '82 BRAT with D/R-4spd, running 175/70-13's got consistant 30 MPG, highest was 31. That was running country roads and some hiway miles on trips into middle Ohio.

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well hell i should be getting damn near 45 mpg with my lil 1980 wagonits got a 1.6 a five speed is fwd and has stock tires straight through exhoust stock everthing on the engine new plugs wires roter and disty compleat new front suspention and steering.(pads,calipers,rotoers,barings,axles,and steering rack.

 

WOW lol.

 

:)

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This really sucks. I am only getting 23 to 24 MPG. I got 26MPG on the hiway. I guess I am going to have to get a Weber and replace the Hitachi.

I am just glad the Brat already has the Weber.

 

 

P.S. This milage is in my 1987 GL Wagon with a D/R 5Speed, and 4WD.

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I need to fill up now and check the actual consumption numbers, because its been over a year (and a pair of headgaskets) since I had a full tank of gas... but my estimate is the 20 ballpark :dead: I REALLY need to do something about it, and the investigation is on very soon. 3.20 a gallon and rising, for ~100 miles a day, maybe average 400+ miles a week.. that 20% adds up quickly.

 

I do mutilate the throttle, but I would think I should be pulling more than 20 mpg.. I got 25 before. :confused:

 

Anyhow, I'll figure my problem out in the next week or so; I just wanted to post it for comparison.

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Always the "economy minded person" daeron, Reg here is $4.77/gallon, Premium (Legacy Turbo) is $5.22/gallon (note: Imperial gallons).

 

The way I *see* it you have two choices:

1) drive it

2) leave it parked in the yard

 

If I didn't have so many projects going, not to mention the unexpected (my water heater laid an egg yesterday), I was/am considering a diesel re-power of a scooter.

Picture it, me on a scooter, it would look like a bear "doing" a foot ball.

Scary stuff!

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The narrower the tires are, the less rolling resistance there is. Series 80 tires has much less rolling resistance than 70's. Also run 40 to 45 PSI in them. Drive with a VERY light foot. Keep speeds below 60 mph. Also set your initial timing as high as you can, up to 14 degrees BTDC. IF you do all of this, you will see 38+ mpg with a stock carbureted 5 speed 4x4 EA82.

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