2015 Ford F150 goes on a diet, loses 700 lbs. (Aluminum)

[MetroMPG]

Originally Posted by Cobb

Does weight really play that much role in mpg?

Source: Fuel Economy Versus Mass - Wired Science (2009 model year data, excludes hybrids)

[War_Wagon]

Originally Posted by Cobb

Does weight really play that much role in mpg? I know Ive read from time to time about people lighten their vehicles and achieve X. I know on insightcentral and youtube Ive neen one of the higher if not highest mpg achievers with the gen 2 insight and I check in at over 6 ft and over 350 lbs. Infact I have to have a special office chair as I brake the ones that are standard issue or stretch them out of shape. Dont forget the 100 lbs of audio gear I carry to listen to loud music on top of that.

Still for a manufacturer to loose 700 lbs and keep all the bells and whistles is something else. I bet one of us could easily knock another 700 lbs off.

Well the rule of thumb at the dragstrip was every 100 pounds of weight removed resulted in a one tenth of a second reduction in the quarter mile E.T. So if my Nova ran a 12.50, and I gutted the interior etc and pulled out 100 pounds, in theory it should run a 12.40 with no other changes. It doesn't sound like a big change, but if we put that in the perspective of everyday driving, I can see how it could add up. A drag car gets rolling from a dead stop once, and it shows an improvement with weight reduction. So, if we made a smaller weight reduction in a car that is in stop and go traffic all day, then I can see it being beneficial to lose 50 pounds off the car, or the driver for that matter! I personally think that reducing unspring rotational mass is where the biggest, easiest improvements are. There is a reason that serious race cars have lightweight wheels and aluminum driveshafts. I can tell the difference in my Civic when the bigger winter tires are on it vs the summers, and that's only a few pounds at the most. Going from steel wheels to lightweight alloys is probably the easiest thing you can do to make a difference in the way your car feels when it comes to weight reduction. I think the rough guideline for rotational mass is 1 to 4. So if you take 10 pounds of mass out of your wheels, it's like taking 40 pounds out of the rest of the car. Someone please correct me if I am wrong, but reducing rotational mass is the first place to find easy weight savings.

Edit: Oh sure MetroMPG, ninja me with your fancy science and charts and whatnot ha ha

[MetroMPG]

You: 1000 words

Me:

[Giovanni LiCalsi]

This is why I am planning to use BST Ducati 1098 carbon fiber wheels and single-sided swingarm on my reverse trike EV.
BST Ducati CF 6lbs.

BST Single-Sided Swingarm 5.5lbs.

[War_Wagon]

Originally Posted by MetroMPG

You: 1000 words

Me:

Ya ya, hey, when we were doing this on our street cars a million years ago there weren't great sites like Ecomodder that could have told us this stuff, we had to figure it out the hard way, so I will tell my longwinded stories to make my point ha ha

[euromodder]

Originally Posted by Cobb

Does weight really play that much role in mpg?

It sure does make it far easier to achieve good mpg.
It's one of the reasons old cars can get such good fuel economy: they weigh far less than the current overweight crop.

Everytime a car is accelerated you're paying for the extra weight - and while you can get some of that back thru gliding or regen, most drivers turn the energy into heat (brakes).

The main benefit is in city / suburb driving with lots of stop (or slow) & go traffic.
Once out on the highway at a constant speed, the effect is minimal.
But then ... going at a constant speed isn't the most efficient way to drive


When going uphill, weight is also a negative factor.
You can't recoup all of that energy when going back downhill as it'd lead to excessive speeds - even in a hybrid or EV, you're done with energy recovery once the battery is full.

Less weight also means less resources being used.
Another benefit.

[CFECO]

Originally Posted by Giovanni LiCalsi

This is why I am planning to use BST Ducati 1098 carbon fiber wheels and single-sided swingarm on my reverse trike EV.
BST Ducati CF 6lbs.

BST Single-Sided Swingarm 5.5lbs.

Motorcycle suspensions and wheels are not designed for side loads, be careful.

[Thenorm]

Originally Posted by War_Wagon

I personally think that reducing unspring rotational mass is where the biggest, easiest improvements are. There is a reason that serious race cars have lightweight wheels and aluminum driveshafts. I can tell the difference in my Civic when the bigger winter tires are on it vs the summers, and that's only a few pounds at the most. Going from steel wheels to lightweight alloys is probably the easiest thing you can do to make a difference in the way your car feels when it comes to weight reduction. I think the rough guideline for rotational mass is 1 to 4. So if you take 10 pounds of mass out of your wheels, it's like taking 40 pounds out of the rest of the car. Someone please correct me if I am wrong, but reducing rotational mass is the first place to find easy weight savings.

thats the rule of thumb that i know. on my autocross car i have a huge spread of wheel weights. my race wheels are uber light 13lbs for a 15x10" wheel, but on the flip side, my street apearance wheels are like 22lbs 17x9". they feel like completely different vehicles. also light wheels make the ride much more comfortable when you hit pot holes etc. there is less mass to accelerate (in the vertical direction) so bumps are less harsh.

[Cobb]

So....... the vehicle weight is in metrics and mpg is in english? Is the mpg a raw conversion to english backed on a gallon or imperial gallon?

Maybe weight effects hybrids differently when hypermiled? There is a large gentleman on the insight form who also got high mpg with his car too.

Originally Posted by MetroMPG

Source: Fuel Economy Versus Mass - Wired Science (2009 model year data, excludes hybrids)

[MetroMPG]

I'm pretty sure it's US gallons - check the source link, provided.

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If a similar chart was made for hybrids, it would look the same.