Practical Weight Reduction Ideas for Daily Driver

[Northwest]

This link is a fantastic write up to reducing weight in these cars and I believe they got it down to 2420lbs quite easily and shaved three seconds off per lap and chased a 6 second reduction.

"Most road racers find themselves on a hunt for tenths or even hundredths of a second at a time, when modifying and tuning their vehicle setup. So where did an entire three seconds come from, and how can we pull out at least three more? First, the D’Garage Ford Fiesta ST lost 140 lbs, bringing the total weight down to 2,420 lbs. Weight loss for any car naturally improves performance by reducing its inertia, the car accelerates and decelerates quicker with less weight resisting these changes in motion. Extending beyond these benefits lies a too-often overlooked performance characteristic: vehicle rotation. A fast rotating car enables the driver to throw it into a turn with quicker response, potentially more speed and a better trajectory path for a higher speed exit."

https://dsportmag.com/the-cars/ford-fiesta-st-build-part-1/

https://dsportmag.com/the-cars/project-fiesta-st-part-two-springs-sway-bar-intercooler-exhaust/

https://dsportmag.com/the-cars/ford-fiesta-st-build-part-3-party-time/

https://dsportmag.com/the-cars/prepping-the-fiesta-st-for-a-full-racecar-conversion/

https://dsportmag.com/the-cars/project-fiesta-st-part-4-adding-more-boost-to-the-ecoboost/

https://dsportmag.com/the-cars/project/project-fiesta-st-part-five-e85-boost-fuel-equals-power/
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I cannot find much information on any fiesta st with a well cell but this could possibly be an option to reduce substantial weight while putting it in a place that matters. I would be curious on the weight savings. Have any of you weighed a gas tank on our cars? I checked ebay to see if I could find the weight on a used one but nobody is saying the weight.

https://www.summitracing.com/parts/...MIjoLPocii7wIVciGtBh2IGw22EAQYAiABEgJ3UvD_BwE

 

[1.6]

Here is another great article about the FiST and weight reduction. I recommend all " The Way of the FiST " articles on that site.

https://www.fordmuscle.com/features/the-way-of-the-fist-part-4-wheels-tires-and-weight-savings/

 

[Fiestig]

just got lithium battery installed. surprisingly it fit fairly well with stock battery tray and tie down. battery is a tad short height wise but not hard to have something thrown under there. may throw something to fill up the gap on the side.

Couple of notes..

I actually made a spacer tray for mine out of some kid foam flooring and punched a bunch of holes in it so not to retain heat

ATX series are somewhat heat sensitive, so it would be good to run a duct to the battery tray to get some cooling when you are in hotter temps. Get the Optimate Lithium 4s charger. Its less expensive and has run like a champ for 3years and counting for my ATX ReStart. Keep in mind that you will need to eventually take your battery out to charge, unless you use the hardwire to the battery for charging while in the car. I use my atx for pretty much fun runs and that is about it.

Ahh, one more point. If you leave the battery just to see how long it lasts as I did and all of the sudden the door locks don't work, get familiar with pulling out key post out of the fob. Hitting the "ReStart" button is quite gratifying though when it starts right up after hitting the button.

 

[Mikey456]

Going back to the title of this thread. Has anyone used the Odyssey PC680? I remember a member (I think dresonant) had one without the Mele battery box and somehow got it to stay in the standard battery case. I remember seeing it but I don’t remember the details of how he mounted it in. I would like to know how he did it and how it works in the long term.

 

[Erick_V]

Going back to the title of this thread. Has anyone used the Odyssey PC680? I remember a member (I think dresonant) had one without the Mele battery box and somehow got it to stay in the standard battery case. I remember seeing it but I don’t remember the details of how he mounted it in. I would like to know how he did it and how it works in the long term.

Here you go, just looked at these earlier this week. I'm likely going to go down the PC680/stock box route when my OEM battery fails. Worst case I don't like it and go with the Mele box which is also mentioned and pictured in these threads.

https://www.fiestastforum.com/threads/odyssey-pc680-battery.14269/

Another thread that talks about the PC680

https://www.fiestastforum.com/threads/track-battery.8037/page-4

 

[Mikey456]

Here you go, just looked at these earlier this week. I'm likely going to go down the PC680/stock box route when my OEM battery fails. Worst case I don't like it and go with the Mele box which is also mentioned and pictured in these threads.

https://www.fiestastforum.com/threads/odyssey-pc680-battery.14269/

Another thread that talks about the PC680

https://www.fiestastforum.com/threads/track-battery.8037/page-4

Thanks for the info. I will look into that route too when my battery needs replacement. I remember one guy did not like how the ECU screwed onto the Mele battery box. I think I’m going to use the factory box and follow the way that others have. It’s a great way to offset the weight added to the front of the car when you add bigger/heavier intercoolers and braces.

 

[Drew J]

I'm leaning more towards holding off on battery swap and BBK for now.

As a consolation, I found another cheap 6 pounds: lug nuts. Stock nuts are about 8oz each from what I can find*, and so by going to 2oz Muteki chrome vanadian nuts, I'm saving 6oz x 16 which is 98oz, or 6 pounds. Not too shabby for $75.

Of course being low to the ground and in the very middle of the wheel, there will be negligible benefit to anything except total weight, though at least it's perfectly balanced front to back and left to right.

*I'm going to weigh the stock lug nuts tonight to verify.

 

[Capri to ST]

I'm leaning more towards holding off on battery swap and BBK for now.

As a consolation, I found another cheap 6 pounds: lug nuts. Stock nuts are about 8oz each from what I can find*, and so by going to 2oz Muteki chrome vanadian nuts, I'm saving 6oz x 16 which is 98oz, or 6 pounds. Not too shabby for $75.

Of course being low to the ground and in the very middle of the wheel, there will be negligible benefit to anything except total weight, though at least it's perfectly balanced front to back and left to right.

*I'm going to weigh the stock lug nuts tonight to verify.

You got me curious, so I just weighed one of the stock lug nuts, and I'm sorry to tell you it's only 1.7 oz. Mine are off the car since I replaced them with aftermarket McGard spline drive lug nuts, so I just grabbed one and weighed it on a little kitchen scale I have.
That would be good weight to save because it's unsprung weight. These are the lug nuts I currently have, and they weigh 1.12 ounces each according to the manufacturer, so that would be a small weight saving-
https://mcgard.com/product/chrome-s...-4-lug-nuts-requires-65300-installation-tool/

Here is a stock lug nut on the scale-

 

[ST-eph]

Personnaly,
I broke down yesterday ...

plastics, belt buckles, and rear window wiper motor. 13Kg (this video)
rear seat 25Kg
1.2kg speakers
carpet and floor: 3Kg JUST REAR

 

[FJ16]

You got me curious, so I just weighed one of the stock lug nuts, and I'm sorry to tell you it's only 1.7 oz. Mine are off the car since I replaced them with aftermarket McGard spline drive lug nuts, so I just grabbed one and weighed it on a little kitchen scale I have.
That would be good weight to save because it's unsprung weight. These are the lug nuts I currently have, and they weigh 1.12 ounces each according to the manufacturer, so that would be a small weight saving-
https://mcgard.com/product/chrome-s...-4-lug-nuts-requires-65300-installation-tool/

Thank you for saving me the trouble of digging through my trash pile to find an old lug nut to weigh - I saw the OP's numbers and said to myself "there's no way those are half a pound each". Good info!

 

[Capri to ST]

Thank you for saving me the trouble of digging through my trash pile to find an old lug nut to weigh - I saw the OP's numbers and said to myself "there's no way those are half a pound each". Good info!

You're welcome, I thought the same thing, that there was no way the stock ones weighed that much, so I figured I would weigh one. My scale isn't super fancy, so the weight might be off by a little bit, but I think it's pretty close.

 

[ronmcdon]

Just wanted to update and say the lithium battery so far a bit of a headache and reconsidering just doing a lead acid battery relocated to the trunk again.

In the past 5 events ive driven out to, 4 times the battery went out. one time I could re-start it right away after using the re-start button. on other occasions had to ask for someone to push my car. Maybe it's more of a crapshot and it's the part in question I have that doesn't work so well. It just seems to happen at random.

 

[Fiestig]

Just wanted to update and say the lithium battery so far a bit of a headache and reconsidering just doing a lead acid battery relocated to the trunk again.

In the past 5 events ive driven out to, 4 times the battery went out. one time I could re-start it right away after using the re-start button. on other occasions had to ask for someone to push my car. Maybe it's more of a crapshot and it's the part in question I have that doesn't work so well. It just seems to happen at random.

Where is your lithium battery mounted? Is it in the engine bay in place of the stock battery? If so, getting it out of the heat will do wonders. What charger maintainer are you using?

Why not do an AGM instead of the Lead Acid if you are not having any luck with the lithium? Just curious

 

[Bull Run]

Where is your lithium battery mounted? Is it in the engine bay in place of the stock battery? If so, getting it out of the heat will do wonders. What charger maintainer are you using?

I have mine in a MeLe battery box at the stock location. The battery is Shorai LFX36L3-BS12 that weighs only about 5 pounds that I had in a Mustang before I transplanted into the Fiesta. It survived near 120F Phoenix area summer days like a champ. I had a lithium battery specific charger/maintainer for Anti-gravity (that one did not handle the heat well and swelled up before dying) but never had to use it on the Shorai unit.

At $280, saving 20+ pounds this way is much more cost effective than getting a CF hood or front crash bar (which I'll likely get after I run out of things to save weight on). I heard that lithium batteries do not do well in extreme cold, but it shouldn't be hard to get a similar sized AGM battery and just swapping them during the winter for folks in colder climate.

 

[Bull Run]

In case you are wondering, going from stock to Cobb catted downpipe saves 4 pounds:

Stock downpipe with the heat shield and bracket: 11.6 lbs
Cobb catted downpipe with header wrap: 7.6 lbs

 

[Bull Run]

Just wanted to update and say the lithium battery so far a bit of a headache and reconsidering just doing a lead acid battery relocated to the trunk again.

In the past 5 events ive driven out to, 4 times the battery went out. one time I could re-start it right away after using the re-start button. on other occasions had to ask for someone to push my car. Maybe it's more of a crapshot and it's the part in question I have that doesn't work so well. It just seems to happen at random.

I had same issues with an Anti-gravity Re-start battery. I replaced it with Shorai LFX36L3-BS12 after it died and no issues so far.

 

[rallytaff]

How much does the factory battery weigh, 30lbs? What's the longest you've let this battery sit and it s
Interesting. I wonder how long it would last with a parasitic drain like a car has? 2 weeks you think?

My car was outside for a month, undriven or started when we went to the UK and started the first time when we came back.

 

[Bull Run]

Installed the TB Performance crash bar last week.

Stock: 21.3 lbs
TB Performance w/ shipping box: 17.5 lbs
Difference: 3.8 lbs

I couldn't weigh the box by itself as my scale's not that sensitive but TB Performance's clam that their bar being 7 pounds lighter seems legit from my estimation.