Car MPG Efficiency Modifications Main
From EcoModder Forum Wiki
You will find a list of more than 65 car modifications that you can do to improve your car efficiency and increase MPG. This is the main wiki page for the list and links to details about how to perform a modification and the efficiency improvement expected.
Visitors to this site that want to get better fuel efficiency should find many ways to decrease their fuel usage with independantly tested improvement results, tested by ecomodder users. Visitors that are interested in these modifications or have other ideas may find the ecomodder forums worthwhile as most of the data in this wiki has been generated by the forum users.
All ecomodder users are encouraged to modify the pages contained in these links with their own experiences, users must sign in to modify pages. For all mods please only list scientifically backed information and please provide supporting references with links. Efficiency improvement results should only be based on back to back tests under the same conditions. If there is no proven tested efficiency improvement listed ecomodders are welcome to estimate an efficiency improvement however please state that it is an estimate.
Any theoretical and untested mods please only include in the unproven mod section below.
For any significant changes or suggestions to this page, please discuss here: Main Mod Page Forum Discussion Link
Drivers can also perform efficient driving techniques for free efficiency gains. See the wiki for a comprehensive list: Efficient Driving Techniques Wiki
See also the EcoModding Projects Pages on the wiki : EcoModding Projects
Contents
Proven or unproven theoretically effective mods
Proven modifications which have been tried and tested will have efficiency numbers associated with the modification in the table
Instrumentation
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Alternative fuel consumption gauges MPGuino DIY and others |
0% to 25% | $50-100 USD | User experience info required | |
| Lean burn indicator | User experience info required | |||
| Wide band Oxygen sensor with gauge | 0% to 54% | $250 | 2 hours | User experience info required |
| ScanGauge OBD-II computer (and similar) | ~26% 3 user average |
$139 USD 3 user average |
48 Mins 3 user average |
User experience info required |
| Thermal imaging | $0-$2500 | Minutes | User experience info required | |
| Vacuum gauge | $25 | 1 hour | User experience info required |
Aerodynamic mods
Aerodynamic Mods - Deletions
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Front license plate removal | User experience info required | |||
| Mud flaps (deletion) | $0 | 1 Hour | More Efficiency Numbers Required | |
| Radio antenna (relocation/deletion) | 0.166% Theoretical improvement |
User experience info required | ||
| Raised wing type rear spoilers (deletion) | User experience info required | |||
| Roof rack (OEM as well as aftermarket) (deletion) | 14.6% Single user |
$0 | 0.5 - 2 Hours | More Efficiency Numbers Required |
| Shave badges, door handles, rain gutters, etc. | User experience info required | |||
| Side mirror/s (delete) | 2.54% 6 user average |
$0 - $4 | 3 Hours | |
| Windshield wiper (deletion) | $0 | 0.5 Hour | User experience info required |
Aerodynamic Mods - Fabrication
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Aerodynamic front bumper cover Swap/fabricate | User experience info required | |||
| Belly pan / under tray | 3.09% Using pessimistic estimates 6 user average |
$21.25 4 user average |
6 Hours 5 user average |
User experience info required |
| Boat-tailing behind tires | User experience info required | |||
| Decrease hood to windshield angle | User experience info required | |||
| Front air dam | 4.73% 3 user average |
$5 3 user average |
1 Hour 3 user average |
More user experience info preferred |
| Front wheel arch gap fillers | 3.23% 1 user average |
$3 1 user average |
1 hour 1 user average |
User experience info required |
| Frontal area reduction | 13.5% estimate Single user |
User experience info required | ||
| Full boat tail | 10.2% 2 user average |
$300 2 user average |
25 Hours 2 user average |
User experience info required |
| Grill block partial or full | 2.89% 5 user average |
$7.50 6 user average |
3 Hours 6 user average |
|
| Partial Kammback | 4% 2 user average |
$12.50 2 user average |
12 hours two user average |
More user experience info preferred |
| Pickup truck aeroshell/fastback bed cover | 7.98% 2 user average |
$300 Single user |
20 hours Single user |
User experience info required |
| Pickup truck tonneau cover (partial or full) | 6% | $300-$1000 | external users | User experience info required |
| Rear corner airflow trip feature | User experience info required | |||
| Rear Spoiler | User experience info required | |||
| Ride height reduction | -0.02Cd per inch of reduction | $250 | 4hr | User experience info required |
| Sealed panel gaps | $0 single user average |
10 Mins single user average |
User experience info required | |
| Side skirts | 1% | $2 single user average |
1 Hour single user average |
Information Required, More Efficiency Numbers Required |
| Smooth wheel covers | 3.56% 5 user average |
$4.50 per wheel 3 user average |
4 Minuets to 1 Hour 5 users |
More user experience info preferred |
| Soften / radius aft edge of front wheel arches | User experience info required | |||
| Tire spats, or fully contoured deflectors | $0 single user average |
30Mn single user average |
User experience info required | |
| Upgrade headlights from "bucket" or pop-up style to aero assemblies | User experience info required | |||
| Wheel skirts rear | 2.69% 3 user average |
$15.5 2 user average |
4 Hours 3 user average |
More user experience info preferred |
| Wheel skirts front | User experience info required | |||
| Wheel Arch Mud Flaps | 1$ 1 user average |
2 Hours 1 user average |
More User Experience Info Required, More Efficiency Numbers Required | |
| Windshield wiper cover | 1.5% single user average |
$10 2 users Average |
2-3 hours 2 users average |
More Efficiency Numbers Required, User experience info required |
Drivetrain Mods
Drivetrain Mods - Engine Mechanical
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Advanced ignition timing | $0-700 | Continuous | User experience info required | |
| Car idle reduction | 22.7% Reduction at idle 0% Engine warm up 0% Accelerating 0% Coasting Single user |
$0 | 2 Hours | More Efficiency Numbers Required |
| Cold air and Ram air for diesels | up to 9% | $0-$400 | 1-4 hours | User experience info required |
| Cold start idle reduction | 0.108 L Maximum saved when started cold Single user |
$0 | 1 Hour | More Efficiency Numbers Required |
| Economy camshaft swap | User experience info required | |||
| Engine kill switch for easier Pulse & Glide / Engine off Coasting | NA | User experience info required | ||
| Engine swap | User experience info required | |||
| Hot / warm air intake for gasoline enignes | $0-$100 | 1-2 hours | User experience info required | |
| Increased compression ratio | 1.4% to 3.5% theoretical increase per point compression is raised | $0-$2000 | 2hr-16hr | User experience info required |
| Lean burn (adjust air fuel mixture) | 20% to 54% | $0-$1,000 | up to 12 hours | Information Required |
| Synthetic oil | LESS than 1% guess Single user |
+$10 per oil change | oil change | User experience info required |
| Use lowest viscosity engine oil recommended by OEM | up to 3% tested by external users | +$20 per oil change | oil change | User experience info required |
| Gapless top piston rings | External user ~3% increase in efficiency | $10-$30 per cylinder | 6-12 hours | User experience info required |
| Turbo charging | up to 20% (w/diesel) | $500-$3000 | 4-24 hours | User experience info required |
| Water injection | 6% tested by external diesel users | $160-$800 | 2-6 hours | User experience info required |
Drivetrain Mods - Engine Accessory
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| A/C delete | $0 | 2 Hours | User experience info required | |
| Alternator delete | 6.25% 2 users |
$0 | User experience info required | |
| Alternator Disable Switch | 5% to 10% | $30 | 1-3 hours | More Efficiency Numbers Required |
| Block Heater | 4% 2 user average |
$52.5 3 user average |
1.5 hour 3 user average |
User efficiency info required |
| Coolant heater | $100 to $700 | 1 to 5 hours | User efficiency info required | |
| Electric coolant / water pump | $160-$500 | User experience info required | ||
| Mechanical to electric radiator fan swap | 14% Single User |
User experience info required | ||
| Power steering delete / manual steering rack swap | OEM's get a 1-2 MPG gain | $0 | 2 Hours | P/S system applies up to a constant 1 to 2 horsepower drag on engine at speed |
| Power steering electrohydraulic conversions Converting a standard continuous belt driven P/S to run only part time by use of electric pump or clutched pump |
OEM's get a 1-2 MPG gain | Lots of $$$$ | Many Hours | P/S system applies up to a constant 1 to 2 horsepower drag on engine at speed |
Drivetrain Mods - Transmission/Differential
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Regear for lower cruising RPM | 12.7% 4 user mods averaged |
$120 | More user experience info desired | |
| Swap from automatic to manual transmission | User experience info required | |||
| Automatic transmission manual gear control (Manumatic) | $5 Single User |
4 Hours Single User |
More Efficiency Numbers Required | |
| Synthetic axle/wheel bearing lube | 1% | $15 | 2 Hours | User experience info required |
| Synthetic transmission/differential oil | 1% | up to $10/Qt. | 1 Hour | User experience info required |
| Torque converter lock up control | 12% estimate | $2 | 2 Hours | User experience info required |
| Use thinnest transmission / differential oil recommended by OEM | ~3% Single User |
$12 Single User |
1 hour Single User |
Electrical mods
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Bigger battery | Install a larger battery for alternator delete or long EOC with lights on | up to $400 | 0.3 to 4 hours | User experience info required |
| L.E.D conversion | done in addition to an alt delete or in addition to solar assist or to free up power if you added other electrical loads, save battery power during lights on EOC | $2 to $243 per bulb | 2-6 hours | User experience info required |
| Solar 12v assist | Removing electrical load from alt. is good for up to +5% or .1mpg per 100w replaced on large SUV vehicles |
up to $3 per watt | 2-10 hours | User experience info required |
Wheel & Tire Mods
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Increase tire pressure to max sidewall | 0.9% coast down distance increase based on 30PSI to 50PSI increase (Single user) |
$0 | 0 | User experience info required |
| Lightweight wheels | User experience info required | |||
| Replace tires with low rolling resistance tires | 3.65-13% External source Users (1) get 6.98% |
User experience info required | ||
| Replace tires with skinniest tires recommended by OEM | User experience info required | |||
| Toe in set to zero | 8.54% Single external user |
0$ | 1 Hour | User experience info required |
| Taller Tires: bigger is better | 0 to +5.7% | $1,000 for a set of 5 truck tires A few hundred for a set of 4 car tires |
1 Hour | User experience info required |
Other Mods
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Aftermarket cruise control | User experience info required | |||
| Cruise control mod: fuel economy logic | User experience info required | |||
| Electric conversion | NA | User experience info required | ||
| General maintenance | NA | User experience info required | ||
| Hybrid conversion | User experience info required | |||
| Weight reduction | Theoretical improvement 0.636% for every 50kg reduction See the wiki for assumptions |
User experience info required |
Motorcycle Mods
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Aero fairings | More Info Required | |||
| Sprocket swap | More Info Required |
New Suggested Mods (Ideas or attempts)
These mods should be moved to the correct section after being well documented.
| Modification | Efficiency Improvement | Average Cost | Time Effort | More Info Required |
|---|---|---|---|---|
| Reduced electrical loads | 0.55% for 50W Theoretical calculation |
More Efficiency Numbers Required |
Dis-proven Mods (Hoax Products and non-working mods)
| Modification | Alternative names | Average $$$ wasted | Time Effort wasted | More Info Required |
|---|---|---|---|---|
| Fuel Magnets | More Efficiency Numbers Required | |||
| HHO | brown's gas | few hundred to well over $1,000 | More Efficiency Numbers Required | |
| Liberator fuel saver | $39.95 | More Efficiency Numbers Required | ||
| Tornado Intake Insert | More Efficiency Numbers Required | |||
| Nitrogen tire inflation | $0 to $50 | Tire servicing | More Efficiency Numbers Required |
