Is it possible a previous owner may have installed the economy 4-speed?
I wouldn't count it out, but the original owner (im the second) was an older lady even when she bought it. I do have all records throughout the 90's and early 00's showing it was always taken to a mechanic to be worked on.
I'd also get your speedometer and odometer tested for accuracy. Seems like maybe the odometer is turning about 1.5x more miles than it should be. Or you are spending a lot more time on the freeway than you have suggested.
I have had the speedometer checked for accuracy because it seemed like I was just flying by everyone else. Turns out, everyone in Foco is just slow at driving.
I probably do about 70% on the highway and the other 30% driving in the city on weekends. I am going to try 85 octane (unfortunately with ethanol) next time I fill up and I will get back to you with what kind of MPG I am achieving. I will then compare it to the most recent fill up I have used with 91 pure.
I'd be curious what he gets with 87 octane ethanol free, comparitively. As I mentioned I have seen that in some states. I used it in my 98 Saturn and achieved 4 more mpgs (over 10% eth) when measuring all hwy miles at 60 mph.
Unfortunately there are only 2 gas stations in my city that offer pure gas. They both only offer the 91 octane, but on my next fill up I am going to try 85 and then compare that to my more recent fill up's with 91. I really won't be surprised if the 91 get's better gas mileage.
2.5 I owned a lot of Saturn's in the 90's and went to two of their homecomings at the factory. Do you know if anyone has put the 1.9 twin cam in a Fiero, it a pretty light motor.
Not that I know of. I have owned a few and liked them. Mine were single cam tho, excellent mpgs. I think most people are looking for a power upgrade and there wouldnt be enough power gained for most people to do the swap.
My Formula averages 26 mpg normally and 24 mpg with liberal use of A/C in mixed driving but leaning to mostly highway with occasional traffic... Stock size tires - 5 speed.
Edit mpg, not mph
Wow I would suspect the formula to have one of the best MPG out of all the V6 fieros. It's very light compared to the GT and has the extra gear. What kind of octane are you using with the car? I would definitely check out spark plugs, injectors, fuel lines and all other components to make sure things are running correctly.
BTW, when you have your A/C on does your rpm's go crazy? Every car I've had has ran just fine with the A/C on but the fiero seems to have an awful idle and makes it unbearable to drive. I'll try to upload a video when I can find a moment to do so.
Running premium (91) fuel without advancing the timing a couple of degrees can cause overheating. Especially in city driving. Fuel still burning late in the cycle causes excessive heating of cylinder head, exhaust, and everything downstream.
You will get better mpg due to increased btu content but not much more than 2 or 3% better. The rest is just placebo effect.
This is the answer. My cars all run better after I wash and clean them too...its not because of lighter weight or smoother surface....lol. I run 87 in everything from my minivan to the 413 Mopar. It ran fine even in my 'premium recommended' other cars too without any problems at all.
Originally posted by zzzhuh: Wow I would suspect the formula to have one of the best MPG out of all the V6 fieros. It's very light compared to the GT and has the extra gear. What kind of octane are you using with the car? I would definitely check out spark plugs, injectors, fuel lines and all other components to make sure things are running correctly.
BTW, when you have your A/C on does your rpm's go crazy? Every car I've had has ran just fine with the A/C on but the fiero seems to have an awful idle and makes it unbearable to drive. I'll try to upload a video when I can find a moment to do so.
My Formulas has all the option and 88's are 50 lbs. heavier, IIRC, than 87's. I believe the Fiero with a V6 was rated ~29 MPG highway, no? So I'm about right on the money all things considered.
You will get better mpg due to increased btu content but not much more than 2 or 3% better. The rest is just placebo effect.
Wrong ethanol has no BTU's or I should say next to nothing compared to straight gas. Selling GM vehicles, I know that mileage drops with ethanol. Plus we have a plant not far from us that makes ethanol. When I was working at a GM dealer in Lowell, the owners from the near by ethanol plant stopped in and we had a nice chat.
[This message has been edited by solotwo (edited 07-02-2014).]
My Formulas has all the option and 88's are 50 lbs. heavier, IIRC, than 87's. I believe the Fiero with a V6 was rated ~29 MPG highway, no? So I'm about right on the money all things considered.
I couldn't find the exact information on what the weight of the car is, but on a different note you have quiet a lucky find! I've only seen 2 formula's in my town. One is in yellow with an automatic and manual window's/mirrors. And the other one is right down the street with less than 20,000 Original Miles and Factory T-tops. The old man wouldn't let it go for any price but the thing unfortunately doesn't run
For some reason I always see formula's being sold for less than GT's
Shouldn't the Formula's be sought after like the Mera considering it's the best year, and it was only made for that year?
My Formulas has all the option and 88's are 50 lbs. heavier, IIRC, than 87's. I believe the Fiero with a V6 was rated ~29 MPG highway, no? So I'm about right on the money all things considered.
An 87 SE V6 weighs 2696 An 88 Formula weighs 2679 Option package will cause some variation. The weight difference between the 87 GT and an 88 GT is 27 pounds, the 88 heavier.
[This message has been edited by olejoedad (edited 07-03-2014).]
I couldn't find the exact information on what the weight of the car is, but on a different note you have quiet a lucky find! I've only seen 2 formula's in my town. One is in yellow with an automatic and manual window's/mirrors. And the other one is right down the street with less than 20,000 Original Miles and Factory T-tops. The old man wouldn't let it go for any price but the thing unfortunately doesn't run
For some reason I always see formula's being sold for less than GT's
Shouldn't the Formula's be sought after like the Mera considering it's the best year, and it was only made for that year?
Kinda, some people prefer the aero nose over the coupe nose which the Formula has. I have a Formula and get 30 mpg highway on 87 octane 10% eth. Mine has no power mirrors or windows or even a trunk popper, no sunroof, and is a 5 speed.
[This message has been edited by 2.5 (edited 07-03-2014).]
86 GT Auto w/87 2.8. No A/C, windows half down, sunroof popped up. Mostly interstate miles, about 100 miles a day. Cruise control set five miles over so 60-75 mph. 87 octane gas.
When someone tells me that gas makes a difference, I do not automatically think the placebo effect has anything to do with it.
Back in my Grand National days, I had a multiple-chip box with external selector. I'm a pilot, so could drive onto the local general aviation airport and park at the airplane. I could also fill up with 100+ octane aviation gas. Leaded, of course, but in that car the cat converter had somehow become... gutted.
Running RICH, an alkyline-based avgas formula provided octane ratings up to 130. ONE THIRTY. ONE HUNDRED THIRTY Even LEAN, it's 100 or better.
In the GN, with wildly advanced timing and aggressive turbo control due to the selectable chip (and after a brief learning period), performance with avgas was incredible - worth every penny, but not as a regular diet. The system would advance timing until knock was sensed, so with avgas it became very aggressive. And the difference between high-octane avgas and pump gas was amazing on the street and measurable on the track:
PUMP GAS with near-stock timing: 12.9 seconds AVGAS with advanced timing: 11.4 NO OTHER CHANGES!
That 1.5 seconds might cost $1-2,000 in tuning and mods, but it was also available from the gas and the gas alone. Avgas is costly. But you could mix 90 octane auto gas with 130 octane avgas 50-50, and get about 110 octane performance (rich). I don't recall anyone in the local Buick group commenting on improved mileage - that was not one of the objectives of the Grand National.
Today, you can buy 100 octane low-lead avgas for about $6 per gallon at most airports. It still has lead in it, and would definitely kill your converter. But that great stuff is easy to recognize: it's BLUE.
So that wonderful GN experience suggests that higher octane and less alcohol CAN make a difference. And maybe that translates to the Fiero... Perhaps someone here has mapped the stock Fiero V6 ECU. Does it also advance until it senses knocking???
Yes, very well understand how well it does in a performance car like the GN. A Fiero is no GN or even close to a performance car. Premium (or high octane) is nearly always recommended in a performance car, especially with higher compression. Higher octane just decreases the risk of pinging. If you want to set your Fiero advance to 45* it will prob need high octane....if it will start. Ill also give you most gas companies put more/better additives in higher priced gas...but its not to produce more power. My Caddy limo recommended premium because of the weight...loaded with 9-10 people it could ping badly especially going up a long grade if you didnt. I used 87 in it because there was seldom more than 3-4 people in it with me and it did just fine. The digital read out for instant gas mileage stayed the same with either gas at 24-25 hwy. Didnt make any difference to power either.
[This message has been edited by rogergarrison (edited 07-04-2014).]
Originally posted by rogergarrison: My Caddy limo recommended premium because of the weight...loaded with 9-10 people it could ping badly especially going up a long grade if you didnt. I used 87 in it because there was seldom more than 3-4 people in it with me and it did just fine. The digital read out for instant gas mileage stayed the same with either gas at 24-25 hwy. Didnt make any difference to power either.
I would disagree with the power difference. I have a 1991 Cadillac Seville 4.9L (Anyone want an engine?) that also requires the premium gas. Put regular gas in the car and it will run alright, but the power is down noticeably. The Instant fuel economy shouldn't necessary be taken into consideration considering it is based off of how your pressing down on the throttle. If you let off the throttle the IE will shoot up to 70MPG. Put your foot down and it will say 1-2MPG.
The Average fuel is the read out you should be looking at. I noticed with regular I was getting about 15-17 with daily driving (I know how sad?) On the other hand, putting premium in makes the throttle response EASILY faster and the gas mileage improves with 18-22.
[This message has been edited by zzzhuh (edited 07-04-2014).]
Originally posted by notaguru: In the GN, with wildly advanced timing and aggressive turbo control due to the selectable chip (and after a brief learning period), performance with avgas was incredible - worth every penny, but not as a regular diet. The system would advance timing until knock was sensed, so with avgas it became very aggressive. And the difference between high-octane avgas and pump gas was amazing on the street and measurable on the track:
That 1.5 seconds might cost $1-2,000 in tuning and mods, but it was also available from the gas and the gas alone. [
Wildly advanced time and aggressive turbo control are not changes with the gas only. You changed the timing and the boost.
Gas makes a difference, but only when it's the right gas for the job. The Fiero's ECM doesn't automatically advance the timing in such a way, just because you threw higher octane fuel in it, nor does it have knock sensors. You're going to have to manually adjust things on the FIero to get any performance or MPG gain from using higher octane fuel. It's not just going to magically happen.
I would disagree with the power difference. I have a 1991 Cadillac Seville 4.9L (Anyone want an engine?) that also requires the premium gas. Put regular gas in the car and it will run alright, but the power is down noticeably. The Instant fuel economy shouldn't necessary be taken into consideration considering it is based off of how your pressing down on the throttle. If you let off the throttle the IE will shoot up to 70MPG. Put your foot down and it will say 1-2MPG.
The Average fuel is the read out you should be looking at. I noticed with regular I was getting about 15-17 with daily driving (I know how sad?) On the other hand, putting premium in makes the throttle response EASILY faster and the gas mileage improves with 18-22.
No, I use the instant readout, not the average because it includes surface street driving too. The instant readout is very accurate if your on a level road running on cruise control. Ive checked it for accuracy. The instant readout will stay the same for 30 mins or more. It only will change going up or down a grade like you said because the throttle will move. It used 4 gallons to top it back off after going 100 miles....thats 25 mpg, just what the instant readout said. I know it goes way up when you coast and down when you floor it...duhhh. Level straight interstate on cruise control is dead on accurate on instant readout. Average readout includes all the roads, stop lights and everything else that affects it. If I remember, the average mileage readout was usually around 17 mpg. That would be correct for the AVERAGE. The instant if done like I said gives you very accurate reading for the exact mileage at the time being read. I dont care what the average is over the last week or month...I want to know what its doing at that exact minute....only. Do it my way, and youll find the reading for instant is VERY accurate. Has been on all my cars that have that feature. Grade of gas has never made any difference at all in my cars performance or mileage. On the 413, I do get more power because if I put premium in it, I bump up the timing more and the premium keeps it from pinging...so in that case I DO have more power. Just changing the gas dont do anything if i leave my timing the same. It starts the same, idles the same, runs the same, mileage is the same. I must have all magical cars. The average readout is useless data at least to me. If I use a tank of gas and can read an odometer, I can give you the average.
Ive been a pilot for 45 years in jet fighters and single engine private planes. Ive owned 8 and still own one i use 100 LL in. I used premium or aviation gas (100-110 octane) in my race cars too because I had very high compression and very advanced timing. The premium allowed that without pinging and destroying the engine. It didnt give it more power or gas mileage...only ALLOWED me to do things to increase the power. Yes, JUST altering the timing can make big differences in performance, even if that is all you do. Thats all I did when I did go drag racing or street racing. One setting for everyday, more advanced for hot rodding. In the days of distributors that was a 5 second job to turn the distributor another 5-10 degrees.
[This message has been edited by rogergarrison (edited 07-05-2014).]
Originally posted by zzzhuh: I have a 1991 Cadillac Seville 4.9L (Anyone want an engine?) that also requires the premium gas.
I may be interested in your engine.
On a side note, I have been able to attain mileage in the mid thirties, but that was with a non-stock computer/tune and good driving habits. I did get into the 40+ range a few times, but this is not good for the engine. This was with an 86 SE V6 4 speed.
[This message has been edited by chetw77cruiser (edited 07-05-2014).]
On a side note, I have been able to attain mileage in the mid thirties, but that was with a non-stock computer/tune and good driving habits. I did get into the 40+ range a few times, but this is not good for the engine. This was with an 86 SE V6 4 speed.
Wow that is insane. Maybe our little 2.8L don't have the most power, but I think with some tuning we could probably get the same mileage the iron duke get's. Any threads on this idea?
Originally posted by zzzhuh: Wow that is insane. Maybe our little 2.8L don't have the most power, but I think with some tuning we could probably get the same mileage the iron duke get's. Any threads on this idea?
7730 ECM, right tune, and right trans, and yes, the 2.8 can get 40 MPG. It's been done before.
When I want to, I can usually beat any factory specs on gas mileage by just being easy on the gas pedal and using cruise whenever I can. A given engine will only accelerate that car so quick and its a waste of gas to push the gas down farther at any time. If it wont go faster than say it does with 1/4 throttle, why push it down more. I also run 40 pnds in all my tires on all cars. If I got 35 mpg every day with my v6 Sebring, I see no reason you couldnt get that or more with a 2.8. My Sebrings rpms were very comparable at cruise speeds to what my Fieros ran. 40 is just a few more than 35. Fiero is a lot lighter than the Sebring. The Sebring did have a 4 spd auto though.
Wow that was a pretty good write up. Very good information, but I saw at least 3 other fiero's in one of the photo's. Do you still have these car's? I could use some of the part's off of that GT.
I think his mileage number has almost everything to do with him living in CO. At 5000' the engine is sucking a LOT less air in, and at speed his car is pushing a lot less air out of the way.
I live in Spokane, and here we're at about 2000', and when around here I get better mileage (measurably so) than when I'm travelling to lower elevations. The car is also much more 'lively' at lower elevations..
Originally posted by zzzhuh: The Instant fuel economy shouldn't necessary be taken into consideration considering it is based off of how your pressing down on the throttle. If you let off the throttle the IE will shoot up to 70MPG. Put your foot down and it will say 1-2MPG.
The Average fuel is the read out you should be looking at.
I agree and would never base my mpgs on what an instant readout told me. Miles per gallon measured by GPS or trip miles and gallons put in at the pump.
Originally posted by aaronkoch: I think his mileage number has almost everything to do with him living in CO. At 5000' the engine is sucking a LOT less air in, and at speed his car is pushing a lot less air out of the way.
I live in Spokane, and here we're at about 2000', and when around here I get better mileage (measurably so) than when I'm travelling to lower elevations. The car is also much more 'lively' at lower elevations..
True, but O2 content is not 50% less. It's still only CO, and not Tibet.
Also, less fuel == less power, so MPG and performance will not both improve, especially with higher octane fuel, where even less of it will be burned at that altitude. MPG gain at that altitude will be more like 20-25% (so roughly 3-5 MPG city, and about 8 on a flat highway).
Or maybe we've burned the sky enough over the last 50 years, that the oxygen content really is 50% lower than sea level in that part of CO now. Too bad our burning all that oxygen hasn't improved MPG for us down here by the beach.
I think his mileage number has almost everything to do with him living in CO. At 5000' the engine is sucking a LOT less air in, and at speed his car is pushing a lot less air out of the way.
I live in Spokane, and here we're at about 2000', and when around here I get better mileage (measurably so) than when I'm travelling to lower elevations. The car is also much more 'lively' at lower elevations..
I think that is a very good thought as far as why my gas mileage could be slightly better than what others are achieving. I am about to fill up on gas so I will be back with my current MPG. The next thing I am going to try is putting in 85 since other members have been suggesting that higher gas doesn't achieve better MPG. I have never put in 85 in my car so I won't be surprised if my mileage goes down as well as the performance. But hey! At least I've got a little bit more money in my pocket right?
Originally posted by zzzhuh: Wow that was a pretty good write up. Very good information, but I saw at least 3 other fiero's in one of the photo's. Do you still have these car's? I could use some of the part's off of that GT.
The only car I do not have from the photos is the black SE that was the test mule. It is now in Texas, but I did replace it with the silver SE I drive now.
I have six total, three non-drivers. Give a call and we can talk swap.
FWIW, this is the 86 SE that I was averaging 35+ mpg on my trips between Walden and Fort Morgan. As can be seen, not much out of the ordinary other than ecu and tune. I run premium when using this setup considering I had quite a bit of timing dialed in. I changed out the ecu before I had a chance to use low grade to quantify any difference. When I get the 7730 in, then I can play again. I did get over 50 MPG one time, but the tail winds that day were close to the posted speed limit in Wyoming.
I agree and would never base my mpgs on what an instant readout told me. Miles per gallon measured by GPS or trip miles and gallons put in at the pump.
Well my odometer reading and the amount to top it back off always confirms my instant readout as I already pointed out. For fun I was on about a 25 mile highway trip today. 70mph on cruise on a level straight intersate. I set it on instant readout. On the way back the same route, I put in on average after resetting it to zero. The reading was identical. Average dropped right after getting off the exit though. Like I said, I prefer the instant mileage so I know what Im doing at that minute. I can get the average over a tank of gas by reading the odometer. Its not hard to figure 20 gallons of gas going 480 miles...with no electronics involved at all. Again, Ive not found a car Ive had to not give an accurate instant mpg reading. 100 miles on 4 gallons comes out the same no matter how you measure it.
Originally posted by rogergarrison: Well my odometer reading and the amount to top it back off always confirms my instant readout as I already pointed out.
It just means you were only considering the readout at a point where it actually read out what the average managed to come to. If you'd reset the average MPG reading at the beginning, it should have read the same value at the end of the trip when you filled up the gas.
All the instant reading tells you is what the computer is calculating your MPG to be at that point in time. It isn't the MPG your car is necessarily going to get over the course of an entire tank of fuel. If it was, we'd have already solved the energy problem, because my truck would be getting 99.9 MPG.
Well I filled up my tank yesterday with regular 85 after using the 91 octane. My average MPG was around 28.6 but that has to do with me doing a bit more city driving than normal.
Since I've put the 85 in I feel the car not being as quick on the acceleration. Call me crazy but my car just seems to not be as sharp. I think after this test im gonna at least use 87 all the time, even if money is scarce.
