Amazing- coefficient of drag and what lift will do to Bronco mpg

[nvrstuk]

Hence the title- The numbers blew me away. I couldnt image that a round driving light would have 10 times the drag that an aerodynamic shaped strut or wing would have.

Check this out.

Multiple times on mpg threads I have shown what lifting a Bronco does to mileage. I used to keep logs on mileage, lube, maintenance stuff and installing a lsuspension or body lift, larger OD tires on my Bronco affected my mileage significantly.

Just thought this youtube video backed that up. Course all you "airplane guys" knew these drastic numbers already!



Here is a great video that all airplane builders have seen or should have seen. Same on cars or anything going through air. Round objects have almost 10 times the drag of a streamlined object with the same thickness.

This video is worth the 5 minute watch.

https://www.youtube.com/watch?v=ftq8jTQ8ANE

 

[SHX669]

Those Old " Stock Car " racers knew all about it and did some creative body massaging - while trying not to get caught - lol

 

[jerry]

I also watched the video and found it extremely interesting. Thanks for sharing!

 

[Boss Hugg]

I suppose I should find a way to use small wire for my axle housings??? LOL. I used to help some guys every now and then in the dirt track racing world. I mentioned to a few how I would build the roof panel to be an "air foil" as they are called. Every bit of downforce is good, and the less drag the better. No one wanted to play like that though because it's supposedly CHEATING. IDK....

 

[ssray]

Hence the title- The numbers blew me away. I couldnt image that a round driving light would have 10 times the drag that an aerodynamic shaped strut or wing would have.

Check this out.

Multiple times on mpg threads I have shown what lifting a Bronco does to mileage. I used to keep logs on mileage, lube, maintenance stuff and installing a lsuspension or body lift, larger OD tires on my Bronco affected my mileage significantly.
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Hmm….looks like there’s a need for wing shaped light bars with a lexan leading edge with embedded leds?

You’ve got ORIs on your rig….how much could you drop the pressure in the upper chambers and lower the ride height when traveling on the highway? Begs this question. Could those be plumbed into a valve system to do adjustments from the seat. Could help with drag if you take a longer road trip. Not sure what that does to ride control though. I like the principle of them and get how they work but haven’t gotten into how they’re set up and adjusted.

Aerodynamics is a fascinating field. A lot of people don’t realize how much higher speeds increase drag. Laminar flow in airfoils is another interesting study. Lower drag but so sensitive to any errors in profile.

Scott

 

[nvrstuk]

It's interesting as heck!!

Talk to world class bicycle racers... they know all about drag. And they know how fruitless it is to try to keep up high speeds due to the almost exponential drag at higher speeds. Stay in the pack and sprint...

 

[toddz69]

It's very interesting but just don't try to take any college-level fluid mechanics courses! Closest I ever came to failing one of my classes in engineering school!

Todd Z.

 

[Yeller]

Added a splitter to the front of a mini truck once and it gained 20mph on the top end and became stable. Don’t know how I’d know what the top speeds were:-X

 

[Broncobowsher]

Explains why the last biplane I rode in had airfoil shaped support cables. You could tell when you were really moving because the wires started whistling. Only got that when going into a dive to get enough speed to do a loop.

They didn't mention the size of the square support rod, I would like to know the size of that. Since the square didn't appear to be as bad for aero as you would think. Might be better than round, but we don't know.

I remember a discussion with some engineers once about aero. The frontal area didn't really matter what the shape was. The shape of the corners is what made a big difference.
Look at box trucks. The top leading edge of the box is typically a sharp square corner. Look at a U-haul and it has a radius.

 

[blubuckaroo]

This me of the Myth Busters show about tailgate up or down.
https://www.youtube.com/watch?v=r3aqHbD-O9E

 

[73azbronco]

My 2020 Ram lowers it's ride height to gain 2mpg.

 

[ssray]

My 2020 Ram lowers it's ride height to gain 2mpg.

Thanks! I wasn’t aware of that on the Rams. Air based I see. Reminds me of back around 1980 I tried running air shocks on the front of the Bronc. Definitely got some lift with them but they didn’t do good things for the handling. Maybe running a second shock with them would’ve helped but we later ditched them and went with the taller truck coils back then. Amazing how the tech has changed over the years.

Scott

 

[73azbronco]

It depends on ram model, mine squats because it has air suspension, others with fixed suspension have an air dam that lowers 2 inchs.

 

[nvrstuk]

I wish I could "push a button" on the dash and have my ORI's fill/empty with nitrogen as I prepare for a long highway trip. Wow, drop 4" out of the current 6" for uptravel and still ride on pillows at 70mph... hit a button at the trail head while airing the tires down and go have fun...

Come on somebody, figure this out so we can do this (w/o losing any oil).

 

[Broncobowsher]

I wish I could "push a button" on the dash and have my ORI's fill/empty with nitrogen as I prepare for a long highway trip. Wow, drop 4" out of the current 6" for uptravel and still ride on pillows at 70mph... hit a button at the trail head while airing the tires down and go have fun...

Come on somebody, figure this out so we can do this (w/o losing any oil).

Have a talk with this guy https://www.youtube.com/watch?v=Ogj_F8sCjIE

 

[nvrstuk]

Dang you Broncobowsher!!! lol

I'm calling King tomorrow am.

 

[lars]

The vehicle in the background has an engine that dynoed at 458 HP @ 5500 rpm. The one in the foreground, 180 HP @ 2700 rpm. And yes, I have dyno sheets on both.

The one in the background can get past 120 mph for a bit, but it's low single digits fuel burn at that speed and not much fun. The one in the foreground can cruise for hours at about 200 mph, averaging about 20 mpg in still air, and can do that for about 4 hours before I start getting nervous and looking for a gas pump.

 

[nvrstuk]

Proof right there!!

 

[rwfid]

Ecomodders has a lot of interesting information on aerodynamics of vehicles. It is amazing what some people have done to their vehicles to gain fuel economy. There is a Toyota T100 on there that a guy lowered the drag coefficient to that of a Prius. I don't know if many people would be brave enough to seen in it though.

 

[bmc69]

Quite a few years ago I wrote a short "paper" with calculations to show why EB mileage was what it is...almost regardless of the engine installed (I included SFC numbers for a number of actual gas and diesel engines, driveline loss estimates, etc). If I recall correctly, I wrote that up in response to the then-current "throw a 4BT in it and get 40 mpg" nonsense that was flying around.

It's what I do for a living...except for high speed ships and craft, not road vehicles. ;-)