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Tips to get better MPG
Thread Starter
Drifting
Joined: Jan 2006
Posts: 1,372
Likes: 2
From: Ramona CA
Tips to get better MPG
Just got this '92 2 weeks ago. Ran it through its 1st full tank of gas. Did 328.4 miles and took 17.54 gallons to fill up. Doing the math:
328.4 miles / 17.54 gallons = 18.7 MPG. I guess I expected more, closer to 20 mpg. The car has a 2.59 rear end. I don't hot rod it. Just drive normal with gradual acceleration.
The car runs really nice, smooth and has been reliable. I drive 70 miles a day to work and back at about 50% highway, 50% city stop and go.
Any tips? Is this normal?
328.4 miles / 17.54 gallons = 18.7 MPG. I guess I expected more, closer to 20 mpg. The car has a 2.59 rear end. I don't hot rod it. Just drive normal with gradual acceleration.
The car runs really nice, smooth and has been reliable. I drive 70 miles a day to work and back at about 50% highway, 50% city stop and go.
Any tips? Is this normal?
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
I'd say that's a little low for 50/50 driving. I normally get 27-28 on the highway and 17-18 around town, so mixed I see low 20's. If you used different gas pumps, they can be inconsistent on when they auto-stop, so do a few more tanks before making any verdicts. Not sure about tips; I shift at like 1800rpm, draft whenever possible, just general good stuff like that.
Race Director
Joined: Sep 2001
Posts: 14,676
Likes: 751
From: NEwhere Ohio
that does seem a little low, are you from CA? maybe theres additives in that gas that decrease MPG.
Ethanol is one such additive.
In ohio, we have summer and winter blends. Higher volatility winter blends, combined with lower air temps give notoriously lower MPG's.
Ive had the best MPG luck with BP and the worst with Marathon. Though this is on my 40+ MPG 5spd toyota corolla where Im really focused on fuel mileage.
Just recently, I did a 400 mile trip and got 18 MPG with 2 or 3% idling and 98% highway - top down with me driving it hard.
However, on the return trip, I put the convertible top up and drove in a civilized manner. I got 24 MPG.
Thats with: 60 lb/hr injectors, procharger supercharger, hotcam, LT headers, custom tune, lightweight flywheel, etc.
If you are comparing your MPG's you need to compare to other 92 and 93 cars. The 94-96 cars have sequential port fuel injection which improves their highway MPG.
As for all the 'I get 32+ MPG' when driving my c4 vette claims!
If they havent been replaced, replace your oxygen sensors. Those are whats directly affectig your part throttle / highway cruise trims.
Wouldnt hurt to do new plugs and air filter also.
Ethanol is one such additive.
In ohio, we have summer and winter blends. Higher volatility winter blends, combined with lower air temps give notoriously lower MPG's.
Ive had the best MPG luck with BP and the worst with Marathon. Though this is on my 40+ MPG 5spd toyota corolla where Im really focused on fuel mileage.
Just recently, I did a 400 mile trip and got 18 MPG with 2 or 3% idling and 98% highway - top down with me driving it hard.
However, on the return trip, I put the convertible top up and drove in a civilized manner. I got 24 MPG.
Thats with: 60 lb/hr injectors, procharger supercharger, hotcam, LT headers, custom tune, lightweight flywheel, etc.
If you are comparing your MPG's you need to compare to other 92 and 93 cars. The 94-96 cars have sequential port fuel injection which improves their highway MPG.
As for all the 'I get 32+ MPG' when driving my c4 vette claims!
If they havent been replaced, replace your oxygen sensors. Those are whats directly affectig your part throttle / highway cruise trims.
Wouldnt hurt to do new plugs and air filter also.
Pro
Joined: Apr 2000
Posts: 696
Likes: 18
From: Jenkintown PA
Just got this '92 2 weeks ago. Ran it through its 1st full tank of gas. Did 328.4 miles and took 17.54 gallons to fill up. Doing the math:
328.4 miles / 17.54 gallons = 18.7 MPG. I guess I expected more, closer to 20 mpg. The car has a 2.59 rear end. I don't hot rod it. Just drive normal with gradual acceleration.
The car runs really nice, smooth and has been reliable. I drive 70 miles a day to work and back at about 50% highway, 50% city stop and go.
Any tips? Is this normal?
328.4 miles / 17.54 gallons = 18.7 MPG. I guess I expected more, closer to 20 mpg. The car has a 2.59 rear end. I don't hot rod it. Just drive normal with gradual acceleration.
The car runs really nice, smooth and has been reliable. I drive 70 miles a day to work and back at about 50% highway, 50% city stop and go.
Any tips? Is this normal?
The best TIP, is to look ahead and anticipate stops or slow-downs. I see more and more drivers never slow down when it is evident that they are going to either have to slow down or stop within a reasonable distance. Besides MPG this will save on brakes too!
SAVE THE WAVE
Race Director
Joined: Aug 2000
Posts: 11,470
Likes: 764
to me, that's about right. i have a 90 auto w/ 3.07 - i average right around 19 consistently, city/highway. my highway mileage is just about dead on 24 mpg. last year i took a 2400 mile round trip trek to florida. probably 95% of my driving was on the interstate. while i did not baby it , i did run with traffic. my average mileage fot the 2400 miles was 23.8 MPG. those figures are calculated, and not computer indicated, and that's what was indicated on my window sticker. there's not a lot i can do about it - when it needs gas, it needs gas!
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Pro
Joined: Jun 2010
Posts: 562
Likes: 0
From: Smyrna ga
my car is telling me (on the dash gauge) that I was averaging 13.5 mpg. Is this normal? I still have to get used to driving like a granny... Ive been heavy footed lately.
Ive been using the instant MPG gauge lately to try and get my granny driving on.
Im going to fill up soon and calculate mpg. But my car is a 96.
Ive been using the instant MPG gauge lately to try and get my granny driving on.
Im going to fill up soon and calculate mpg. But my car is a 96.
Thread Starter
Drifting
Joined: Jan 2006
Posts: 1,372
Likes: 2
From: Ramona CA
'92 with LT1.
I will change the plugs and the O2 sensors.
What O2 sensors are recommended? How many are there?
What plugs are recommended? My C5 takes NGK TR55s.
Is the cat a dual cat or separate cats. Any recommendations for high flow cat?
I will change the plugs and the O2 sensors.
What O2 sensors are recommended? How many are there?
What plugs are recommended? My C5 takes NGK TR55s.
Is the cat a dual cat or separate cats. Any recommendations for high flow cat?
Safety Car
Joined: Jun 2006
Posts: 3,629
Likes: 28
From: FL
Race Director
Joined: Sep 2001
Posts: 14,676
Likes: 751
From: NEwhere Ohio
each cat has a single o2 sensor upstream.
I recommend Bosch brand o2 sensor (vs. AC Delco).
NGK TR55's are the best. Dont go with any of the fancy iridium plugs or anything like that. What happens is they have a smaller tip on them that is more susceptible to being fouled -leaving you with a no-start condition. (Conditions that would cause them to get fouled include a malfunctioning o2 sensor, optispark issues, engine turned on and off before warmed up fully, etc.)
That reminds me, be wary of any skips or hesitation in acceleration. If you are not familiar with the optispark, that is the distributor. It is very susceptible to having its seal break and moisture get in. Once moisture gets in there it corrodes the rotor. My 1993 w/ 26000 miles had a bad optispark in 2001. Later model c4's (i think 95 and 96's) had a vent system to flush out any moisture. If you replace your optispark, you can upgrade to a vent system.
Safety Car
Joined: Dec 2008
Posts: 3,588
Likes: 10
From: North New Jersey
I would say little low considering 2.59 ratio...I do about 2 MPH better w/3.07 at 50/50 mix.
The best TIP, is to look ahead and anticipate stops or slow-downs. I see more and more drivers never slow down when it is evident that they are going to either have to slow down or stop within a reasonable distance. Besides MPG this will save on brakes too!
SAVE THE WAVE
The best TIP, is to look ahead and anticipate stops or slow-downs. I see more and more drivers never slow down when it is evident that they are going to either have to slow down or stop within a reasonable distance. Besides MPG this will save on brakes too!
SAVE THE WAVE
Its mostly about driving style because our Vettes can get similar fuel economy as a 4 or 6 cylinder...I get about 19-22 50/50 city/highway with my 3.07 gears and an automatic.
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Safety Car
Joined: Feb 2000
Posts: 3,771
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From: MANDEVILLE, LA La
A couple of factors to consider.
1) How fast was your Highway Speed. 60 gets a few better than 80.
2) Tire Pressure 3-5 Psi can make a difference.
3) With or against the wind and the wind speed.Can be costly on mileage
4) A/C on or off? Good for a couple MPG's.
5) Hilly or Flat Terrain..Hills can eat Fuel.
6) And of course Tune Up Condition as stated previously.Plugs, Air Filter,O2 Sensors, very important especially if approaching 100K Miles.
Might do a road trip all in one day to get a better read out.
1) How fast was your Highway Speed. 60 gets a few better than 80.
2) Tire Pressure 3-5 Psi can make a difference.
3) With or against the wind and the wind speed.Can be costly on mileage
4) A/C on or off? Good for a couple MPG's.
5) Hilly or Flat Terrain..Hills can eat Fuel.
6) And of course Tune Up Condition as stated previously.Plugs, Air Filter,O2 Sensors, very important especially if approaching 100K Miles.
Might do a road trip all in one day to get a better read out.
