The MythBusters The MythBusters

MythBusters Episode 209: Moonshiner Myths

Premier Date: January 11, 2014

A moonshine still can malfunction and explode with enough force to destroy the shack in which it is housed.


In the shop, Adam built a copper still from scratch and Jamie acquired an industrial milk canister and modified it for use as a still. They distilled a fermented corn mash mixture to obtain 156-proof moonshine, noting that they had obtained the necessary permits to do so legally.

At a bomb range, they built a small shack and placed Adam’s still inside. The still’s condenser outlet was plugged to simulate a clog in the tubing that would cause pressure to build up. The boiler was loaded with pure ethanol and heated; there was no explosion after 30 minutes, but significant amounts of smoke and flames were observed. They found that the still had been destroyed by fire, and Adam theorized that gradual failure of the welds had let the ethanol vapor escape slowly enough to burn rather than explode.

For a second full-scale test, Jamie’s still was set up in a new shack, heated, and allowed to vent its vapor into the shack until an optimally-flammable concentration was reached. They used an electric spark to ignite a rag in the shack, representing a cigarette being lit by an unsuspecting moonshiner. The resulting explosion blew the shack apart, so Adam and Jamie declared the myth confirmed.

A car can run properly on moonshine instead of gasoline, without modification.


The Build Team decided to test the operability, performance, and longevity of cars running on moonshine. For operability testing, they obtained three cars of the same make and model, but from different decades: 1970s (carbureted), 1990s (fuel injected), 2010s (fuel injected, modern). With 192 proof moonshine in the fuel tanks, each car was driven on a course designed to test acceleration and maneuvering. In the 1970s car, Tory struggled with the engine stalling and was unable to complete a full lap. Grant completed one lap in the 1990s car, but stopped on the second lap after his engine began to stutter and lose power. Kari, driving the 2010s car, was able to finish three laps even though she noted slower-than-normal acceleration. The 2010s car was used for the remainder of the experiments.

For the performance testing, the team tested three different strengths of moonshine: 151 proof, 170 proof, and 192 proof in a 0 to 60 mph (97 km/h) acceleration test. The car would not start on 151 proof, it averaged 19.4 seconds on 170 proof, and averaged 9.0 seconds on 192 proof (96% ethanol). Next, at Petaluma Speedway, Tory drove 3 laps running gasoline and 3 laps running 192 proof moonshine. The lap times in the moonshine-powered car were marginally better. Tory noted that even though the acceleration was slower on moonshine, the effect gave him better control on the dirt surface of the track.

For the longevity test, they went to Thunderhill Raceway Park. Grant, in a moonshine-fueled car, attempted to outrun Kari and Tori in an identical but gasoline-fueled car. Grant was able to stay ahead of them after 3 laps totaling almost 10 miles (16 km). The team declared the myth confirmed, but Kari commented that standard car engines are not designed to run on ethanol and that it gives poor gas mileage.