Jalopnik is click-city this morning thanks to an old article by Bradley Brownell titled:“Porsche Put 12 Pounds Of Extra Weight In My Car To Make It Nicer To Drive, So I Threw It Away.” Keen to get in on the clickidy-doodas, I’m penning my own story about a gigantic 265 pound cast iron counterweight bolted to my (possibly stolen) 1957 Willys FC-150 — a counterweight that I’m very much not throwing away.
Bradley’s story is so compelling because when people think about sports cars, they envision lightweight, precision-machined parts and top-notch engineering. The idea of a Porsche containing the single simplest car part in the history of machine design and one that goes against the very ethos of any sports car dynamicist — a big-ass mass — boggles people’s minds. But it’s true, as Bradley wrote in his story:
Because the Volkswagen-sourced Type 4 aircooled four cylinder isn’t quite as refined as Porsche’s internally-balanced flat-six engine, the geniuses in Stuttgart figured that they could tack on a dozen extra pounds to the transmission crossmember to keep those vibrations from reaching its delicate customers.
As surprising as it might seem that an automaker would just add weight to a car, especially given what car manufacturers are resorting to these days to reduce heft to meet strict emissions regulations, this kind of thing has been standard process in the industry for decades.
Think about all the weight carmakers add to vehicles to improve noise, vibration, and harshness (NVH). I’m talking engine covers, sound-deadening foam, carpet insulation, door panel mats, and on and on. As a closer parallel to Bradley’s Porsche’s weight, a number of automakers use mass to tame vibration — even sports cars like the 2020 Toyota Supra, which has a big hunk of what looks like cast iron bolted to the rear subframe:
Ram has tuned mass dampers bolted to its 1500’s frame rails. Called Active Tuned Mass Modules (ATMMs), these canisters actually shake their internal weights. Check these out:
Here’s a short description of the ATMM’s from my 2018 article on the then-new Ram 1500:
As the HEMI engine’s Multi-Displacement System kicks in, and sends the truck into four-cylinder mode, an underhood sensor picks up unwanted vibrations, and triggers these ATMMs to shake their internal weights in a way that’s 180 degrees out of phase with the engine’s unwanted vibration, thus canceling it out and yielding a smooth experience for occupants. This concept is called destructive interference, and it requires tweaking to the ATMMs depending upon the frame length.
But none of these – and certainly not the Porsche’s meager 12 pound weight — compare to the boat-anchor I have strapped to the back of my sketchy 1957 Willys FC150.
It’s called a counterweight, and it’s there to improve the vehicle’s weight distribution, which — with the engine mounted right above the front axle, and not much more than a rear axle and a fuel tank (mine has been removed) in the back to counteract that inline-four — is precariously front-biased.
The massive counterweight, which — per the for-sale listing of the counterweight shown at the top of this article — weighs either 265 or 275 pounds, spans the distance between the two frame rails, just ahead of the rear bumper.
The weight is one piece, and contains four holes — two on each side to receive rectangular U-bolts like the ones shown below; notice how there are small plates welded to the top of the frame, presumably to locate the U-bolts to keep the counterweight from wanting to slide:
It’s hard to tell, but I’m fairly sure the counterweight also fastens to the frame’s rearmost crossmember just ahead of the rear bumper. In any case, it’s almost 300 pounds of weight just thrown onto the back of a Jeep to prevent the thing from flipping up on its nose during braking, and there’s nothing more primitive than that.
It’s worth noting that Willys-Overland used to bolt massive cast iron weights onto the fronts of some Jeeps, too — particularly Jeeps equipped with Power Takeoff units that ran heavy rear draw bar-mounted equipment like plows and post hole diggers. Without a counter-weight, ramming a plow into dirt would likely pick a Jeep’s entire front end up off the ground.
Some performance cars over the years have also included ballasts to improve weight distribution. In racing applications, like the The FIA World Touring Car Cup, teams add weight as a “Balance of Performance” measure to level the playing field. Here’s more from the racing series’ website:
Calculated using average lap times from qualifying at the first two events of the season, the compensation weight rule is designed to further level up the performance of the competing cars by effectively adding more weight to the faster cars to try to slow them down.
An additional 40 kilograms will be added to the Audi RS 3 LMS at the Slovakia Ring – on top of the existing 20 kilograms for using the previous-generation ECU, the Honda Civic Type R gets a weight increase of 50 kilograms, while it’s 60 kilograms for the Lynk & Co 03 TCR
Anyway, since so many people were enamored by Brad’s Porsche’s big chunk of metal used to quell NVH issues, I figured I’d share how big chunks of metal have been used to solve even simpler problems. Yep, sometimes car engineering isn’t so hard.
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