PART 14: WEIGHT REDUCTION THE HARD WAY
Busted Knuckles and Sweat - How to Get Rid of Sound Deadener

So there it was, a stripped down to the bare shell (almost) chassis sitting on 4 jackstands in my garage. No parts to install..no rust to repair...nothing really to do. Or so I thought. Weight as we all know is the root of all evil on the track. Get the car as light as you can and you will go faster. How simple can it be? Until it comes to getting rid of the weight. Back to the carcass in my garage. Seems as if cushy street cars have a little extra poundage that can be removed in the form of sound deadening material. Don't need THAT stuff in a racecar! Lets get rid of that. Easier said than done. Sound deadener is basically a 1/8 inch thick tar mat that is draped over most of the lower interior surfaces of the car under the carpet. It is applied hot so sticks to the metal it is applied to. It not only protects the metal but reduces vibration and noise to the cockpit and occupants...and is a royal PITA to remove. Two trains of thought on how to get rid of the stuff 1) heat it and scrape it off as a gooey mess or 2) freeze it and hammer and chip it off. I chose the latter approach. This is an ugly ugly job to do and is very time consuming. Typically, the best approach is the buy dry ice and cool the tar based sound deadener so that it becomes so brittle it can be hit with a hammer and cracks off the chassis. Lucky for me where I live it was only in the high teens to low 20's for a period of time (Mid-January) so who needs dry ice....if you can handle working in the cold! After about 12 hours of chipping away at the sound deadener it’s all gone to the tune of about 20 Lbs of weight savings. Thsi includes all the tar based deaneder on the firewall. Some work with brake cleaner to clean up the remaining residue and the interior actually looks pretty decent, like a sponsored race car!

A lot of hard work chipping away at the sound deadener. Here shown with most removed. Even the firewall gets hit (red arrow).
Hit the areas with some brake cleaner and voila...no more sound deadener and a much better appearence and 20 pounds in dead weight gone.

But wait there's more. In addition there was a large section of sound deadening “padding” on the cars firewall. This is a fiber cloth backed in thick plastic. It runs the entire width of the firewall and is placed behind all the under-dash components including the pedal assembly. To remove all of it virtually all the components must be removed. The dash had to come out and the clutch/brake pedal assembly must be removed to get at it all. The benefit... a total weight savings of about 10lbs also.
The material to be removed - fiber cloth backed plastic. Look Ma ..no pedals!

There was one more thing I wanted to tackle and that was a bit or wiring simplification. Nothing really to be gained here other than peace of mind. The rear half of the car has but two electrical demands - juice for the fuel pump and juice for the tail lights. So why is the wiring bundle two inches in diameter? How about wires for the sound system, the hatch defroster, seat belt warning stuff, and a few other minor loads. So with an hour or so to spare I split the rear harness removed all but the essential wires and wrapped it back up. There was negligable wright savings but a harness that now makes sense and will certainly make things easier when it comes time to trace any electrical maladies. And before you ask I am not masochistic enough to try this on the front main wiring harness. Although I'd like to it simply is too much.

So starting from scratch a total of about 30 lbs can be removed from the car in sound deadening material alone. Add to that a cleaner look, and reduced wiring headaches the interior is ready for some parts installation.


30 pounds od dead weight (it was actually enough to fill two bags). Removed wiring - about 3/4 of the entire bundle.


Hooptie to Hotrod: Part 1
Scrap Metal: Part 2
Cosmetic Fluff: Part 3
Brake Gravy: Part 4
Exhaust Work: Part 5
Dieting and Some Oil Cleanup: Part 6
Cooling Hacks: Part 7
Underhood Miscellaneous: Part 8
Interior Gauges Plus: Part 9
Own a Lincoln? Suspension Upgrades: Part 10
New Shoes: Part 11
What's Next: Part 12
A Twist: Part 13
More Suspension Work: Part 15
Some Heart and Soul: Part 16
Chapter II: To Jump to the Next Series of Installments: Begins with Part 17 - A Good Rear End


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This page last updated April 12, 2004


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