Hidden NVH steel bars? Free weight loss

[S14Wolf]

Was replacing a fender liner today because a tire had rubbed through on it and found a huge steel sprung weight behind the passenger one liner. Looks just like good sized chunks of steel in there. One is easily 12" long and the other is the size of a deck of playing cards. All bolted in. OK to remove? Any idea how much they weigh? I was running out of daylight so didn't have time today but if it's ok then I'll go back in. See no mention of them or their weight in the search.

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[TeeLew]

Take it off and have a closer look. Does it serve any purpose? That doesn't look like the other mass resonators on the car.

 

[NGOT8R]

Why do you think your tire rubbed through the liner? I notice you have the Steeda Pro Action Coilover Struts. I am considering those for my car with 150 pound springs, but I’ve read that they lower the car. I’m wondering if that is the case of your tire rubbing the liner? How do you like the Pro Action Stuts overall?

 

[S14Wolf]

Why do you think your tire rubbed through the liner? I notice you have the Steeda Pro Action Coilover Struts. I am considering those for my car with 150 pound springs, but I’ve read that they lower the car. I’m wondering if that is the case of your tire rubbing the liner? How do you like the Pro Action Stuts overall?

Because I have 305/30/20's on the front and I was doing 150mph in Mexico and the front liner blew in. Less than 1" tire to fender gap. That's why. FYI I run 400lb/in springs on my steeda coilovers on mine. I tried running 250lb per in springs and I was running out of travel into coil bind all the time. Convertible is a little hefty with the Whipple and large heat exchanger but love the 400's.

 

[StangTime]

It has a pony on it. Therefore it must be important? Very odd looking thing. Following to learn more.

 

[junits15]

They are resonators to improve NVH.

Ford puts these all over the car, they are strategically sized placed and coupled so that they cancel a specific harmonic. Basically they caught some sound or vibration that they didn't like during testing and added these resonators to cancel it out. The more you look the more of these you will see.

they are all safe to remove, however you may notice an unpleasant sound or vibration without them. They aren't very heavy, but if you're gutting the car it would help.

 

[2morrow]

I believe they are deleted in GT-350's (or at least my race mechanic says). He states they're ~5lb weight savings per side IIRC.

Much like OP, my fender liners have 1 foot in the grave and upon removal, I will remove these as well.

 

[Nightmonkey]

Short: Keep it!

Long: That's an absorber weight, I expect them to exist on all modern convertibles.
It is not used to cancel out vibrations in the high-frequency range, but in the low-frequency range.
It is therefore not about any feelable vibrations, but about minimising the body deformations in a certain low frequency range, which generally always occurs when the car is moved (keyword: natural frequency).
Sure, you can leave them out, just like you can leave out balancer shafts on the engine, but it has an effect on the durability / service life of components (keyword: continuous vibration load).
Either bearings are subjected to higher loads and wear out more quickly or vehicle structures are overstressed and crack or break more quickly.
So it is not for comfort but for structural integrity.

 

[GTP]

Because I have 305/30/20's on the front and I was doing 150mph in Mexico and the front liner blew in. Less than 1" tire to fender gap. That's why. FYI I run 400lb/in springs on my steeda coilovers on mine. I tried running 250lb per in springs and I was running out of travel into coil bind all the time. Convertible is a little hefty with the Whipple and large heat exchanger but love the 400's.

I converted the plastic push rivets over to screws into body clips at the front lower edge of my front fender liners. (For track days.)

I've been wondering if it is paranoid overkill, but maybe not after reading your post.

 

[Paul McWhiskey]

Short: Keep it!

Long: That's an absorber weight, I expect them to exist on all modern convertibles.
It is not used to cancel out vibrations in the high-frequency range, but in the low-frequency range.
It is therefore not about any feelable vibrations, but about minimising the body deformations in a certain low frequency range, which generally always occurs when the car is moved (keyword: natural frequency).
Sure, you can leave them out, just like you can leave out balancer shafts on the engine, but it has an effect on the durability / service life of components (keyword: continuous vibration load).
Either bearings are subjected to higher loads and wear out more quickly or vehicle structures are overstressed and crack or break more quickly.
So it is not for comfort but for structural integrity.

So, basically, if you’re gonna track it, lose ‘em. If you’re gonna drive it daily, keep ‘em.
Seriously, if you need to loose every pound, because it is ONLY a track car ( how many vert track cars are there) you might consider taking them out. For everyone else, think twice. Is 5 pounds worth it for your application? Just be serious.

 

[bankyf]

My 2020 PP1 does not have those. I know for sure, because that's where I mounted the solenoids and map sensor for my boost controller.

 

[StangTime]

Interesting. So these are dampers that only convertibles get.

 

[Nightmonkey]

Interesting. So these are dampers that only convertibles get.

I can not claim for sure, but that's my experiance with other cars, that are produced not only as convertibles.
Just the convertibles had these weights.
Maybe someone can take a look in the parts lists and confirm?

 

[S14Wolf]

10lbs is 10lbs. People gonna buy an antigravity battery and holder to save 25-30. Free 10. I'd really like to shave 100lbs between driveshaft, battery, carbon fiber hood, and dead weights. Since I've changed the suspension frequency by springs, shocks and brake weight change, I'm not sure how much those are doing.

 

[2morrow]

10lbs is 10lbs. People gonna buy an antigravity battery and holder to save 25-30. Free 10. I'd really like to shave 100lbs between driveshaft, battery, carbon fiber hood, and dead weights. Since I've changed the suspension frequency by springs, shocks and brake weight change, I'm not sure how much those are doing.

All valid points, especially the suspension piece. You can probably throw in lighter wheels and wider tires too.

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