Jon Elson's Machining Page

A short history of E. J. Potter

(or: So you thought Evel Kneivel was a wild and crazy guy!)

I don't know where E. J. Potter came from, the first time I became aware of him was when he was racing/showing off his exotic motorcycle. He took a Harley Davidson frame and put a small-block chevy engine in it, sideways. This engine had Hilborn injectors and burned Nitro, and was producing about 500 Hp. It was started by having a couple guys hang on from the side, and it was pushed with a truck. When the engine fired, the assistants lifted the rear of the bike (these must have been some strong guys!) and put it up on a wooden stand that kept the rear tire, a 10" wide racing slick, off the ground. When the christmas tree said go, E. J. would rev the engine to 6000 RPM and the assistants would push him off the stand! It did a wheelie about half-way down the strip, and did about 160 MPH in the quarter mile. E. J. tried to find a small, light clutch for the thing, but he never found anything that would work. He tried helicopter clutches, but even they didn't quite do it. The rear wheel was coupled to the engine with a huge multi-width roller chain. Well, one day he reached the end of the strip and closed the throttle, and nothing happened - the throttle was stuck! He cut off the magneto, but a very hot engine (no radiator, just the thermal mass of the water in the block) burning nitro at wide open throttle doesn't need much ignition! It kept right on running. He hit the brakes (dual caliper aircraft brakes) and that slowed him to about 150 MPH, but he could feet the handle retreating under his grip. There was no fuel cutoff! As he was approaching a line of trees at the end of the strip, he took the only action he could think of, he jumped off! He slid on his rear until it burned through his chaps into his skin, and then did some somersaults. Amazingly, he ended up being able to walk after all this, and followed the new gap into the forest to see what became of his machine. All he could find was an engine block! Nothing else recognizable.

Realizing that this was a bit more dangerous than he imagined, he started thinking of ways to make life safer, and while continuing with a rebuilt 327 CID bike (with, amazingly, a fuel cutoff!) he started to design his next generation machine. He got an old Dodge Dart station wagon and put an Allison 17xx CID V-12 airplane engine in the back, hooked up to something like a Borg Warner truck transmission. I don't know how he ever heard another sound after being inside a station wagon with an 1800++ horsepower engine. Anyway, there were some problems with the new machine, but it certainly was a crowd pleaser, and it did fairly good times on the clock, too. He felt that his new exhibition machine was a whole lot safer. Then, something happened. I suspect he couldn't leave well enough alone, and had to soup-up that Allison! Well, the engine blew apart one day, and he felt himself in a bit of deja-vu, sliding down a drag strip at 100+ MPH on his rear, again! This time, he was wearing Nomex, and had a racing seat still strapped to his rear, but the somersaults at the end were just as hard on the body!

Well, maybe giant engines are dangerous - so he had to get the engine OUT of the car! How can you do that? Ah ha! Make the "World's Fastest Slot Car" is how! So, he put another Allison on a flatbed trailer, hooked it to a locomotive dynamo, and laid copper strips down the length of the track. He gutted an old Honda Civic (back when they were little more than tin cans, anyway) and put four rewound jet engine starter motors in the Honda. Aside from brake rotors, there wasn't much else in the car but those 4 motors, 4 wheels and tires, and a seat! Well, it WENT! I don't remember the times, but it was FAST! This thing weighed something like 800 Lbs, hardly more than the drive train on a rail. It would beat the rails off the line like they were standing still. No tire burning, just 4 racing slicks pulling the car like a rock out of a sling shot. I think the rails sometimes caught up at the far end, since the Honda wasn't really designed for 300 MPH aerodynamics. This all takes the history up to maybe 1975 or so. I haven't heard any more stories about E. J. Potter since the slot car. I wish now that I had taken the opportunity to SEE this in person. All I know about this is from reading magazines, and I'm sure it would be MUCH more memorable to have actually SEEN it!

For more info, see his WEB PAGE at :

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