kgrif
Viper Owner
Not that it matters but just to make sure I am hitting normal. What kind of mileage can you expect on the road?
Miles per gallon
- Thread starter kgrif
- Start date
tim721
Enthusiast
my father has a '94 that averages 18mpg...
KenH
Enthusiast
I get about 11 around town and 20 on the open freeway.
--- Ken
--- Ken
Torquemonster
Enthusiast
I put up a thread about this a while back - the interstate cruising range was 16mpg to 28mpg - depending upon driving style and tune I guess. Most seem to get 20-23mpg driven steady, the 28mpg was exceptional and only reported by one owner - that car probably ran a bit leaner and had a bit more vacuum advance.
For normal driving - incl. city and highway etc - a lot of heavy footed guys seemed to get between 8-16mpg per tank.... a big range I know - but a big engine is dramatically affected by your right foot. A Viper could probably go from 4-5mpg racing at a track to the interstate figures above and everything in between.
For normal driving - incl. city and highway etc - a lot of heavy footed guys seemed to get between 8-16mpg per tank.... a big range I know - but a big engine is dramatically affected by your right foot. A Viper could probably go from 4-5mpg racing at a track to the interstate figures above and everything in between.
RT/ED
Enthusiast
This past weekend heading up to the Traverse City Wine Tour sponsored by the Motor City Viper Organization. I averaged 25.54 mpg. I was amazed considering that a group of us were pushing it pretty hard most of the way. I suspect the upgrades listed below have contributed to higher than average mpg. 
Snakester
Enthusiast
I average around 16MPG in mixed driving, and just got 23MPG on a long trip (to and from the drag strip) last weekend. My best MPG is 26MPG, which I had gotten a couple times before I put in 3.55 gears.
-Dean.
-Dean.
I've averaged 14.5 mpg over 32,000 miles in the RT/10. Seldom used 6th so I do not believe I have encountered the 20+ mpg periods.
I have averaged around 12.5 mpg for 2600 miles in the SRT. Same driving style.
BTW Torquemonster vacuum advance went the way of the distributors back in the 80's. I am sure you knew that. If one could drive in 6th at a slow speed and not getting on the throttle they could achieve a very high mpg. My right foot does not have that capability. I did not buy the Viper to conserve fuel. I got it to use it as fast as possible.
I have averaged around 12.5 mpg for 2600 miles in the SRT. Same driving style.
BTW Torquemonster vacuum advance went the way of the distributors back in the 80's. I am sure you knew that. If one could drive in 6th at a slow speed and not getting on the throttle they could achieve a very high mpg. My right foot does not have that capability. I did not buy the Viper to conserve fuel. I got it to use it as fast as possible.
Viper Wizard
Enthusiast
The best for me: 160 mile trip, 24.2 @ 80 mph 1500 rpm [75% of the trip]! 
Torquemonster
Enthusiast
Ron - yeah - I still think in the old terms on some stuff - but the ECU's should be advancing more spark at cruise than under load and leaning out at cruise as well for both emissions and mpg reasons.
Effectively it is vacuum advance - except that it's now part of the ignition map - which I assume would be 3D on the Viper. Also, while factory settings should be the same on all cars - I'm sure there is a slight variation between different Vipers within a tolerance level... but that's an assumption as I'm not a tuner and you'd know better than me. Whatever - even if all ECU's are exactly the same - engine build/machining quality will vary from Viper to Viper and explain why some go better than others/get better mpg etc IMHO.
Do you agree?
Effectively it is vacuum advance - except that it's now part of the ignition map - which I assume would be 3D on the Viper. Also, while factory settings should be the same on all cars - I'm sure there is a slight variation between different Vipers within a tolerance level... but that's an assumption as I'm not a tuner and you'd know better than me. Whatever - even if all ECU's are exactly the same - engine build/machining quality will vary from Viper to Viper and explain why some go better than others/get better mpg etc IMHO.
Do you agree?
GTS Bruce
Enthusiast
25MPG at slow cruise between 95 and 110 mph in 6th gear. Bruce
Torquemonster I would assume that for max fuel economy driving wouuld be primarily under closed loop conditions, keeping f/a near stoich. Spark would be expected to be at or near mbt as well. Control maps are multi-dimensional in comparison to the engine speed and vacuum controlled distributors of old. Think of the old systems as 2 unadjustable curves that together defined spark timing. No adjustment for coolant or inlet air temp, no non-linear points for critical regions. No adjustment for rates of throttle input, no knock sensing (course the Viper does not have that either), etc. All in all the systems of old were archaic and did not get the most out of an engine, either peak performance or fuel economy. Todays systems pretty much maximize things but have new limiting factors such as cat temps, rates of pressure rise, emissions, etc and reliability issues like valve and seat temps as that aspect is maintenance free for the lilfe of an engine. Remember when a valve job was a common event?
Torquemonster
Enthusiast
Ron: I remember helping my dad do a few valve lap jobs by hand with the grinding paste :0 no 4 angle jobs back then ;-)
Remember the Chrysler "Lean Burn" engines - or did you not get those. They came out in Australia/NZ end of 70's early 80's - they had the small block V8 getting well into the 20's mpg on carb - using a special ignition setup that allowed fuel ratios of 16-17:1 and very high vacuum advance. Must have been something they did to keep EGT's out of the danger zone with that combo.
I've often thought water injection would be excellent in that role - run very lean plus high advance at cruise and use water to keep EGT down. I've heard others have done it and got exceptionally good results but I've never tried it myself. I've only used water for boost intercooling - and for that it was the best value for money I spent otherwise I'd had to detune or spend more on a larger intercooler and lose throttle response.
Remember the Chrysler "Lean Burn" engines - or did you not get those. They came out in Australia/NZ end of 70's early 80's - they had the small block V8 getting well into the 20's mpg on carb - using a special ignition setup that allowed fuel ratios of 16-17:1 and very high vacuum advance. Must have been something they did to keep EGT's out of the danger zone with that combo.
I've often thought water injection would be excellent in that role - run very lean plus high advance at cruise and use water to keep EGT down. I've heard others have done it and got exceptionally good results but I've never tried it myself. I've only used water for boost intercooling - and for that it was the best value for money I spent otherwise I'd had to detune or spend more on a larger intercooler and lose throttle response.
genXgts
Enthusiast
Not sure what I am doing wrong, wait a mintue, I know what I am doing right!!
I have never pulled in over 10mpg on a tank since I bought the car, ever.
Road racing at Cayuga speedway with the boys it was somewhere around 2mpg, I was on fumes and had to limp over to the 1/4 mile side and shoot in a gallon of 110 to get me to the nearest gas station. Filled up again and back to the track for more fun.
On a good full throttle run from a dig to say the top of 4th the gauge drops down and doesn't quite return to where it was at a stop, always thought that was kinda neat!
I have never pulled in over 10mpg on a tank since I bought the car, ever.
Road racing at Cayuga speedway with the boys it was somewhere around 2mpg, I was on fumes and had to limp over to the 1/4 mile side and shoot in a gallon of 110 to get me to the nearest gas station. Filled up again and back to the track for more fun.
On a good full throttle run from a dig to say the top of 4th the gauge drops down and doesn't quite return to where it was at a stop, always thought that was kinda neat!
The last 20 days worth of logs:
Total Volume - - Total Miles - - MPG - - - Avg. MPG
466.706 - - - - - 7,811 - - - - -16.064 - - 16.736
453.509 - - - - - 7,599 - - - - -17.645 - - 16.756
442.911 - - - - - 7,412 - - - - -20.746 - - 16.735
434.572 - - - - - 7,239 - - - - -17.702 - - 16.658
422.144 - - - - - 7,019 - - - - -17.069 - - 16.627
Total Volume - - Total Miles - - MPG - - - Avg. MPG
466.706 - - - - - 7,811 - - - - -16.064 - - 16.736
453.509 - - - - - 7,599 - - - - -17.645 - - 16.756
442.911 - - - - - 7,412 - - - - -20.746 - - 16.735
434.572 - - - - - 7,239 - - - - -17.702 - - 16.658
422.144 - - - - - 7,019 - - - - -17.069 - - 16.627
Walt McFarland
Enthusiast
I've modified the engine a bit further and need to update my signature but I'm getting about 11 around town and 18 or so on the highway.
Earlier this summer I filled up with Sunoco 94, got right on the freeway, got into 6th gear as soon as possible, drove 100 miles and checked my mileage--best case. Got 23.4MPG on an engine making 600HP at the crank. Have to say I was impressed (however, keeping my speed down for those 100 miles almost killed me).
Earlier this summer I filled up with Sunoco 94, got right on the freeway, got into 6th gear as soon as possible, drove 100 miles and checked my mileage--best case. Got 23.4MPG on an engine making 600HP at the crank. Have to say I was impressed (however, keeping my speed down for those 100 miles almost killed me).
Viperfreak2
Enthusiast
Doesn't sound like we deserved the gas guzzler tax. An F-150 won't get that kinda MPG's, and they only sell 900,000 of those (with no guzzler tax) All together I paid $9000 in the last 4 years of GGT.
snowmann
Enthusiast
Not to sound offensive, but I gotta ask why do you do this?
slaughterj
Enthusiast
- Joined
- Mar 6, 2001
- Posts
- 5,266
- Reaction score
- 0
I get around 11mph solely town stuff, usually get 14mph mixed driving, 20-22mph mostly highway.
Joseph, I hate to say it but I record the same info. All oil, fuel etc are recorded along with when and what mileage. So I can graph average fuel economy and fuel economy per tank just as Bonkers showed. For my RT/10 I can show where modifications actually improved fuel economy such as revised calibration and headers/exhaust. Both improved it by reducing the f/a ratio in open loop times.
Then again it could just be the engineer syndrome. Damn engineers keep track of everything
Then again it could just be the engineer syndrome. Damn engineers keep track of everything
snowmann
Enthusiast
Joseph, I hate to say it but I record the same info. All oil, fuel etc are recorded along with when and what mileage. So I can graph average fuel economy and fuel economy per tank just as Bonkers showed. For my RT/10 I can show where modifications actually improved fuel economy such as revised calibration and headers/exhaust. Both improved it by reducing the f/a ratio in open loop times.
Then again it could just be the engineer syndrome. Damn engineers keep track of everything
Good grief, if I was tracking all that "data" I don't know if I would even enjoy the car.
Torquemonster
Enthusiast
You must be the most discplined driver here - in British/Euro gallon terms - you've got 33.3mpg out of a Viper!!! See how many 418rwhp Euro cars can get 33.3mpg! (US gal. = 3.9 liters; British Gallon = 4.547 liters)
Walt - that is mighty good for 600hp! Sorry about the cramp in your right foot from lifting off
ledfoot
Viper Owner
Ah..................10mpg overall....ledfoot......
Jay Lopez
Enthusiast
On the track I get 4 mpg.
cgmaster
Viper Owner
I keep tract of mine to monitor engine performance and problems.
Torquemonster
Enthusiast
...well?
Is she?
My Cajun Queen is!
No one believes me when I say I drive 50-80k a year for fun. Plus I'm an analyst by trade so I just can't seem to stop myself. I have every gas, repair, oil change reciept since May 5, 1997 - all 410,257 miles / 17 cars worth of them.
Plus its a great refernce tool when someone asks "What kind of mileage does a viper get?" or "How much is the yearly costs of a viper?" ect . . . (Not that anyone ever asks that around this site...)
dwhitt
Viper Owner
I seem to average 15 to 16 mpg
