According to www.feuleconomy.gov My model of fiero (I have an 85GT 6 cylinder 5 speed) gets an average of 22mpg and i get about 15.5 miles per galleon. I dont know if its me or the car, what does anybody eles get??

84 se 4 cyl 4 speed, ~30 mpg mixed driving.

you have to take into account that was when the car was new, things where out the engine gets tired that sorta stuff. that doesn't actaully sound to bad maybe a full tune up, plugs, wires, rotor, coil would be in order and go from there, also if you have a cat still on there car check that and make sure its not clogged, maybe pull it right out and put some straight pipe in or get a nice hi-flo one.

with my 3.4L pedal to the floor all around town 16MPG
Highway @ 80PH 32MPG
Highway @ 100MPH 22MPG

quote Originally posted by FI3RO85GT: According to www.feuleconomy.gov My model of fiero (I have an 85GT 6 cylinder 5 speed) gets an average of 22mpg and i get about 15.5 miles per galleon. I dont know if its me or the car, what does anybody eles get??

Your configuration is confusing...the 85GT wasn't offerered with a 5 speed. So I'm curious what 5 speed you have and the ratios.

Anyway 15.5 is really low for a stock motor. Even in heavy city traffic you should not get below 20 mpg. On the highway my 2.8 5 speed with easily get over 30 mpg and mid 20s in miixed city and highway.

I get about 23-26 in my automatic '85 GT. The engine is in real good shape. I drive it pretty easy, don't quite have the disposable money for a conversion, yet, so I don't want to be too hard on the 2.8.

I suppose when conversion Fiero's start bringing $40k at Barrett-Jackson, which I believe will happen, I'll find the money.

Aw yes, my favorite topic. First you must know that one of my goals in life or at least it seems that way is to acheive the best gas mileage possible from my cars. Having said that, then you have the right to assume that I'm one of those folks that drives the speed limit (most of the time). My mileage is only calculated on higway trips, combo driving is too sporadic IMO to honestly guage how your ride is doing. BTW, I only own 88 notchbacks.

I just checked my 4.9 this week, it got a pretty good 33.7 miles per gallon. Needs a tune up though and an alignment.

My 3800SC is around 34.5 most of the time I don't drive it near as much so some of that time is spent warming it up per se.

My 3.4 push rod Fiero really sucks with the 3.33 final drive, I am only getting 23.4 as a best, that's gotta change, hoping to slap a 5 speed G'trag into it sometime soon.

My 88 Formula T Top car which is stock is pretty good considering the 120+K miles, she's still kicking over 30 mpg but I honestly don't drive her very much.

But, my best mileage car is my 88 Coupe, 4 cylinder 5 speed Isuzu Fiero. I have gotten (Best by Far) up to 46.75 miles per gallon in it.

My kids that also drive my Fieros can't ever get as good gas mileage as I do but then again, they aren't buying the gas so every light that turns green is a race to the next light.

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Ron
Land of the Free because of the Brave. Most gave some, some gave all. Some ran the other way.

my car is origanally a 4 speed but i turned it into a 5

About 6 MPG, yes six. But there is no way you can drive that hard on the street for that long.

You may not want to use this number in your average as it will blow the bell curve

Edit. It is a stock 2.8 with simple exhaust and intake mods allowed by the rules.

[This message has been edited by SCCAFiero (edited 04-01-2007).]

Here is mine:

ECM upgrade and a 4T60, 4 speed auto

3,754 mile trip and got 36.912 mpg mixed driving

[This message has been edited by Capitol City Fiero (edited 04-02-2007).]

I have a 3.4 turbo with a getrag 5 speed and get 25 to 29 mpg on the highway at 75 plus mph.

[This message has been edited by hnthomps (edited 04-01-2007).]

quote Originally posted by FI3RO85GT: my car is origanally a 4 speed but i turned it into a 5

At 15 mpg I would be looking to put the 4 speed back in.

When I only used my '87 GT auto for very short trips(<2 mi), I got around 16 mpg. The engine would never get warm enough to be efficient. So maybe it's just you and how you use your car.

Hmmm this makes me want to test mine out.

The safe numbers I know I can reach are 144 miles in town, and 200 on the highway. 87GT with 3.4 pushrod (with 4k on the engine).

'88 Iron Duke with a five-speed, I get around 22-23 in town and around 30-31 on the highway as long as I don't drive her too hard. Around town, driven with a heavy foot, I get around 18-19.

My stock Formula 5-speed with 170k miles averages about 20 mpg on a tank with mostly in town and spirited driving.
On my trip to D7 I got 28 mpg on the highway, with a trunk full of crap tools and luggage for the week and the AC on - all while cruising at about 80 mph most of the way.

I got a best of 33 mpg one one highway trip that was all highway, light traffic and no-AC, etc. Definitely a best case scenario.

quote Originally posted by Formula88: My stock Formula 5-speed with 170k miles averages about 20 mpg on a tank with mostly in town and spirited driving. On my trip to D7 I got 28 mpg on the highway, with a trunk full of crap tools and luggage for the week and the AC on - all while cruising at about 80 mph most of the way. I got a best of 33 mpg one one highway trip that was all highway, light traffic and no-AC, etc. Definitely a best case scenario.

weight has almost nothing to do with highway driving, unless there are lots of hills. I find that cruise control is not the most efficient way to drive either. I let the car slow down going up the hills.

Ok. Well, I was using the cruise control most of the way.
I have always been under the impression that weight was a big contributor to gas consumption. Guess that's mainly in town?

27mpg mixed driving.
Driving some backroads and a bit of Autobahn I averaged 30mpg once

With my tweaked 2.8 and TH125 slushbox, I'm averaging around 18.5 MPG. Most of that is driving short distances around town. I don't drive like grandma, either.

That said, my car really needs a better transmission. The TH125 is a boat anchor.

18 city
23 hwy
5 spd
LT1

quote Originally posted by lurker: 84 se 4 cyl 4 speed, ~30 mpg mixed driving.

I got 28 mpg coming back from Daytona. Stock 84 4-cylinder, 4-speed manual, using cruise control.

I drove my stock 88GT, T-Top, V6, 5 speed from Sweden to Germany. 400miles. Got 26mpg. All Autobahn at @ 90mph.

The Indy gets about 28 - 30 on the highway.

The 87 GT gets about the same.

I think I'm doing pretty good on gas, I have the same tank of gas in the car when I bought it 6 months ago. Oh wait, I haven't even started the car yet since I bought it. Oh well I guess that don't count then... LOL

I get 11-13mpg. Yes, sure do. I have a 86 GT with minor internals done. But, the catch is that I have a 4 speed with the 4:10 gear. The performance is nice but the mpg is not.

.

[This message has been edited by JazzMan (edited 04-18-2009).]

TBI 4.5/4t60, 2,000+rpm stall converter gets 24 in town and 30+ on the highway.
The old 3.4 GT got 20/20 when it had the 4.10's and after swapping to an Isuzu 5 speed, it still got 20 in town but the highway mileage jumped to 30.

My 86 GT with 4.9 and 4t60e was getting 32 on the highway. After the "Big Blow" in New Orleans, I get 26/27 on the highway. Gas prices are up but we are stuck with "cheap" gas. My 4.3 S-10 was getting 27 and now gets 21. Go figure.

I don't know why yet, but my 86 GT 4 speed gets better mileage than my 86 coupe 4cyl auto. When I first started driving the coupe it was getting 27-28 around town. Now I'm lucky to get 23. I think part of it is the current blend of gas. The change started about the time they started putting the ethanol in the gas. Might be a coincedence, but I doubt it.

quote Originally posted by FI3RO85GT: According to www.feuleconomy.gov My model of fiero (I have an 85GT 6 cylinder 5 speed) gets an average of 22mpg and i get about 15.5 miles per galleon. I dont know if its me or the car, what does anybody eles get??

87GT V6 3speed Auto - about 30 on the hiway, low 20's intown ( high idle )

87GT V6 5seed manual - never got above 15 no matter what i do.. ( i think its the aftermarket ECM chip the OE installed.. i need to get it out of there before i start driving it again. at nearly 3 bucks a gallon it would kill my wallet )

86 GT, 3 speed auto, stock except WCF intake with Amsoil EaA filter (I'll NEVER go back to K&N!!) and I get mid to upper 20's depending on how I drive.

My last long trip makes people jealous. 600 miles round trip so I think it was pretty accurate. With the 3 speed I was 3000 to 3500 rpm almost the whole time, passing a lot of others, and still got spot-on 30mpg!

[This message has been edited by FieroGT42 (edited 04-03-2007).]

86 GT auto, 2.8 cammed and big heads. about 18-20 mpg combined

20ish mpg highway at 75 mph
12ish mpg at 100+mph

My 88 coupe I have seen as high as 40 mpg and it normaly gets 38 highway and about 30 around town. My 88 GT has been getting from 18 to 25

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Don Pottorff
Maroon 88 GT
Red 88 2M4
Silver 86 2M4
Red 85 GT 1:18 Scale

86GT, 3.4 Pushrod pretty tweaked, 4spd manual, high idle I need to track down...

16-19 around town

21-25 on the highway

88 Coupe, 5-speed and the powerful 2.5. From April through November @72 mph and 116 miles daily a very consistent 39mpg.

Johngee