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  #1  
Old 03-01-2011, 04:48 PM
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stodg73 stodg73 is offline
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Default Better MPG's Through Aerodynamics

Better MPG’s through Aerodynamics

In order to get better fuel mileage through aerodynamics, you need to clean up the vehicle aerodynamically. This means putting a type of filler material in all the front holes, body seams, bumper, radiator intake, etc., anywhere air can enter the vehicle, to keep it from going through the vehicle. These vehicles have massively square front ends, which causes the air to be pushed in front of the vehicle, not around, over, or under it. The front of the truck is about the same size of a 4’ x 8’ sheet of plywood, which is 32 square feet. When Dodge went to the newer body style, they did help with the aerodynamics somewhat. You will never be able to get your truck totally cleaned up aerodynamically, but there are things that you can do to make it better:

1. Close up/cover holes in the front end.

2. Reduce the size of the radiator opening/grill.

3. Remove mud flaps if you have them, unless required by law.

4. Fill in body gaps.

5. Fold down mirrors when not towing.

6. Keep the tailgate up when driving highway speeds. (This reduces downforce on the rearend, thereby making the rearend lighter.)

7. Purchase or use a tonneau cover or a topper.

8. Try and make the underside of your vehicle smoother by using metal or plastic to smooth the airflow out.

9. Flat faces are not aerodynamic, try and make things curve around the item in question.


There are a few other things that you can do to get better MPGs:

1. Reduce the weight you are carrying.

2. Use narrower tires, with a highway tread, if possible.

3. Drive slower if possible. Drag increases exponentially as speed increases.

4. If you are pulling a trailer, use a topper, air dam/wing to get the air flow above the trailer face.



With these suggestions you should get about a 1-2 MPG increase.

How to get better MPG's

Lifted trucks are more aerodynamically challenged, there is more wind resistance due to being higher off the ground. Still if you try a few of these things, you might be surprised. Also, larger and wider tires cause more drag, due to being heavier, along with more aggressive tread patterns. The idea is to get the air flowing around and over the vehicle and not having turbulent air around the vehicle.

References:
This site is for Formula 1 cars and Indy Cars and how most of the aerodynamics affects those types of cars. Indy Cars & F1 Cars definitions
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O.O., 01.5, Dodge, 2500, High Output (H.O.) Cummins Turbo Diesel (245/505), Quad Cab Long Bed (QCLB), 4x4, Sport, Original Bosch VP 44 Injection Pump, 6 Speed/NV5600 Transmission, 3.55 Gears, 105k, currently stock engine, Fram Air Filter, 285/75R16s, Glow Shift Gauges: Fuel Pressure (FP), Boost, Exhaust Gas Temperature (EGT), Oil Temperature, SMARTY@1, Airtex lift pump 19 psi @ idle, 14 psi @ WOT, Propane Injection, 2 Stroke Oil, Intake Air Temperature (IAT) Fooler = Better MPG, Bed Lined, Chrome Nerf Bars, more to come!!

Toys:
'79 CJ5, 258ci, 3" lift, 33x12.50x15, Stock Engine and 3 Speed Tranny
'05 Suzuki, GSX1300R, Hayabusa, All Stock, #3('00 blown engine, '00 stolen, & '05)
The complete live & learn and pass it on by H. Jackson Brown, Jr.
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  #2  
Old 03-01-2011, 11:00 PM
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Good article...

Cruise control is your friend for average people...

But if your really looking for MPG number lock your throttle. What I mean by that is when you set cruise control it keeps the speed constant but accelerates or decelerates to maintain but what if you hold your throttle even and not change it?

Well just tinkering today I flipped on the TPS display and watch how trying to hold 55 MPH I could vary over 8% to 20% of throttle try to hold 55 MPH constantly. So now I set my throttle to 12-13% and hold my foot even now allow the truck to ease back against the throttle and roll over the hills. Yeah my speed varies from 45-60 MPH but now my MPG's jumped from 21-22 to 25 MPG today at the high point.

There is all kinds of tricks out there but how impatient are you to get to your point B...
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2002 Dodge Ram 2500, 5.9L Cummins Turbo Diesel, 5 Speed NV4500 transmission, 4x4, 3.55 Gears, AirDog 150 fuel pump with 1/2" Big Line Kit, Stock Bosch VP44 Injection Pump, Bosch RV275 Injectors +40HP, Edge Comp Performance Box, BHAF (Big Honkin' Air Filter), Stock Holset HX35W Turbo, Straight 3" Pipe Exhaust, Crankcase Vent Mod, High Idle Mod, MPG / IAT fooler Mod, ScanGauge II, 25% Tinted Windows, DiPricol Gauges (Fuel pressure, Boost, Pyrometer), 235/85 R16 tires mounted on 16x7 Aluminum mags (weighing 62#), Custom Fog Lights, Custom Backup lights, Silverstar Headlights, 23-24 MPG

1996 Dodge Ram 1500, 5.9L Magnum V8 Gasoline Engine, 46RE Automatic Transmission, 4WD with CAD axle with 3.55 Gears, Mopar Performance PCM, Gutted Kitty, ScanGauge II, 35% Tinted Windows, 16-17 MPG

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  #3  
Old 04-20-2011, 08:56 AM
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Here is a paper from Cummins about how to get better MPG's with aerodynamics. You can adapt it from the big rigs to your truck.

Cummins White Paper in PDF for better MPG's
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O.O., 01.5, Dodge, 2500, High Output (H.O.) Cummins Turbo Diesel (245/505), Quad Cab Long Bed (QCLB), 4x4, Sport, Original Bosch VP 44 Injection Pump, 6 Speed/NV5600 Transmission, 3.55 Gears, 105k, currently stock engine, Fram Air Filter, 285/75R16s, Glow Shift Gauges: Fuel Pressure (FP), Boost, Exhaust Gas Temperature (EGT), Oil Temperature, SMARTY@1, Airtex lift pump 19 psi @ idle, 14 psi @ WOT, Propane Injection, 2 Stroke Oil, Intake Air Temperature (IAT) Fooler = Better MPG, Bed Lined, Chrome Nerf Bars, more to come!!

Toys:
'79 CJ5, 258ci, 3" lift, 33x12.50x15, Stock Engine and 3 Speed Tranny
'05 Suzuki, GSX1300R, Hayabusa, All Stock, #3('00 blown engine, '00 stolen, & '05)
The complete live & learn and pass it on by H. Jackson Brown, Jr.
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  #4  
Old 04-20-2011, 09:15 AM
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Aerodynamics are a great thing, but if you don't want to install them, speed is the next factor. Just for some numbers, with my set up at 55-60 mph I get about 14 mpg, 65 mph I get about 12 mpg, and at 70 about 10 mpg all under the best conditions. I have also found that the fairing in my picture did nothing for mileage due to the fairing being too far in front of the trailer. All it did was move the bug line up about a foot.
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Old 04-20-2011, 01:04 PM
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Another one that is surprising... Warmer intake air helps with MPG's I know older 12V truck had no way of measuring IAT temps really (grid heater) but on the 24V trucks they seem to like the IAT temp around 100-140*F for good solid MPG's in the 20's.

Quote:
2. Use narrower tires, with a highway tread, if possible.
There is a bit more to this. Rolling resistance (tread design and tread width) also rotational mass (or the weight of wheel assembly). Now with narrow tires with a standard tread face will have lower rolling resistance than a agrressive offroad tire that is oversized. Then it take less energy to accerate a lighter wheel assembly that a heavier wheel. So in stop & go traffic oversize tires or just plain heavy tires will degrade MPG more than a skinny light tire.

Quote:
3. Drive slower if possible. Drag increases exponentially as speed increases.
As you accelerate over 55 MPH you need to look into aerodynamic more so than anything. If you have a leveling kit or any kind of mod that increases height of the truck I highly suggest you remove the mod or drive slower because pushing 6-7 foot tall truck through the wind at 70-75 MPH
is just not going to get good MPG numbers... Like holding up a 4x8 sheet of plywood in the wind. :sarcasm:
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2002 Dodge Ram 2500, 5.9L Cummins Turbo Diesel, 5 Speed NV4500 transmission, 4x4, 3.55 Gears, AirDog 150 fuel pump with 1/2" Big Line Kit, Stock Bosch VP44 Injection Pump, Bosch RV275 Injectors +40HP, Edge Comp Performance Box, BHAF (Big Honkin' Air Filter), Stock Holset HX35W Turbo, Straight 3" Pipe Exhaust, Crankcase Vent Mod, High Idle Mod, MPG / IAT fooler Mod, ScanGauge II, 25% Tinted Windows, DiPricol Gauges (Fuel pressure, Boost, Pyrometer), 235/85 R16 tires mounted on 16x7 Aluminum mags (weighing 62#), Custom Fog Lights, Custom Backup lights, Silverstar Headlights, 23-24 MPG

1996 Dodge Ram 1500, 5.9L Magnum V8 Gasoline Engine, 46RE Automatic Transmission, 4WD with CAD axle with 3.55 Gears, Mopar Performance PCM, Gutted Kitty, ScanGauge II, 35% Tinted Windows, 16-17 MPG

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  #6  
Old 04-27-2011, 03:01 PM
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Additional information from Cummins...
http://cumminsengines.com/assets/pdf...whitepaper.pdf
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Michael Nelson - AKA: Mopar1973Man - Forum & Articles
2002 Dodge Ram 2500, 5.9L Cummins Turbo Diesel, 5 Speed NV4500 transmission, 4x4, 3.55 Gears, AirDog 150 fuel pump with 1/2" Big Line Kit, Stock Bosch VP44 Injection Pump, Bosch RV275 Injectors +40HP, Edge Comp Performance Box, BHAF (Big Honkin' Air Filter), Stock Holset HX35W Turbo, Straight 3" Pipe Exhaust, Crankcase Vent Mod, High Idle Mod, MPG / IAT fooler Mod, ScanGauge II, 25% Tinted Windows, DiPricol Gauges (Fuel pressure, Boost, Pyrometer), 235/85 R16 tires mounted on 16x7 Aluminum mags (weighing 62#), Custom Fog Lights, Custom Backup lights, Silverstar Headlights, 23-24 MPG

1996 Dodge Ram 1500, 5.9L Magnum V8 Gasoline Engine, 46RE Automatic Transmission, 4WD with CAD axle with 3.55 Gears, Mopar Performance PCM, Gutted Kitty, ScanGauge II, 35% Tinted Windows, 16-17 MPG

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Old 04-27-2011, 07:28 PM
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There is a real simple way to get better mileage out of your truck in its present state. Just keep your boost BELOW 5 PSI on your gauge.
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1996 RAM "Custom Ground" 100 plate 3/4 forward, 300 injectors, 16.5 timing, Goerends Auto = 365HP, 833TQ Third Gen Rims, Aluminum Headache Rack
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Old 04-28-2011, 09:25 AM
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Quote:
Originally Posted by MnTom View Post
There is a real simple way to get better mileage out of your truck in its present state. Just keep your boost BELOW 5 PSI on your gauge.
To agree with you...

"Keep your boost below 5 PSI and Pyrometer under 600*F and 20+ MPG's wiil happen"

Just that towing trailers or hauling longer this no longer applies...
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Michael Nelson - AKA: Mopar1973Man - Forum & Articles
2002 Dodge Ram 2500, 5.9L Cummins Turbo Diesel, 5 Speed NV4500 transmission, 4x4, 3.55 Gears, AirDog 150 fuel pump with 1/2" Big Line Kit, Stock Bosch VP44 Injection Pump, Bosch RV275 Injectors +40HP, Edge Comp Performance Box, BHAF (Big Honkin' Air Filter), Stock Holset HX35W Turbo, Straight 3" Pipe Exhaust, Crankcase Vent Mod, High Idle Mod, MPG / IAT fooler Mod, ScanGauge II, 25% Tinted Windows, DiPricol Gauges (Fuel pressure, Boost, Pyrometer), 235/85 R16 tires mounted on 16x7 Aluminum mags (weighing 62#), Custom Fog Lights, Custom Backup lights, Silverstar Headlights, 23-24 MPG

1996 Dodge Ram 1500, 5.9L Magnum V8 Gasoline Engine, 46RE Automatic Transmission, 4WD with CAD axle with 3.55 Gears, Mopar Performance PCM, Gutted Kitty, ScanGauge II, 35% Tinted Windows, 16-17 MPG

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