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Every now and then, you see a vehicle build that just went above and beyond what your brain thinks is possible. Upon seeing Leroy Edwards’ open-air hot rod at Sick Week 2024, my brain was definitely thrown for a loop. This thing is wild! There’s no better way to describe it. The build is so vastly different from just about any I’ve personally seen before that I knew I had to pull Leroy aside for an interview and an Engine of the Week feature.
We caught up with Leroy on day two of Sick Week at Bradenton Motorsports Park. We had seen some pictures of the hot rod before Sick Week started, but seeing the car in person was a must. Between the frame rails, the hot rod features a ProCharged 572 cid big block Chevy engine that is also nitrous assisted. According to Leroy, the build took him two and a half years.
“I’ve been a mechanic for over 50 years, and I’ve been a hot rodder for longer than that,” Edwards says, who is on YouTube as Leroy the Master Mechanic. “I’m from St. Louis, MO, and the Corvette plant used to be in St. Louis. I got to ride in a Corvette as a kid and when the guy took off, he was banging gears – that car was all over the place. I’ve been chasing that feeling ever since.
“The inspiration for this hot rod was wanting a car with all the systems exposed. Then, the drag-and-drive bug hit and I knew I could do this. I started with the frame, which I made out of chomoly. It has a 10.1 NHRA legal roll cage, like any other Funny Car. Then, I had to decide what engine I was going to put in it.”
Leroy opted to build his big block Chevy engine using a World block that he got from Bill Mitchell Performance. Inside, the engine has almost all Crower internals – crankshaft, connecting rods, rocker arms, lifters, and camshaft. Leroy chose JE pistons to complete the rotating assembly and AFR 385cc cylinder heads, as well as Chevrolet valve covers.
“You can’t really tell right now, but it’s actually a nitrous motor,” Edwards says. But, nitrous motors run out of air, so that’s why I added the supercharger. It’s a ProCharger F3-136. It’s not the smallest one, but it’s one of the smaller ones. The supercharger itself can support 3,000 horsepower, and I’ve got four 500-horsepower nitrous nozzles in the intake. The problem right now is I’m having to learn how to use the car. We’re going to work with the supercharger first before we turn the nitrous on, and I left the bottles off to lower the temptation.”
The big block Chevy engine is mated to a 4L80E transmission and a Reid case. It has full electronic controls and no manual valve body. According to Leroy, that way you can manage the pressure when you’re not on the power because they don’t need to have that high of pressure all the time. Leroy can control the application of that power by cutting the engine power while it shifts, so he’s not beating up the transmission.
“4L80Es also have a lockup torque converter and you can change when it locks and even how it locks,” he says. “I’ve got a Strange S60 axle housing with 35 spline axles and no spool. The wheelbase is too long to use a spool. It wouldn’t want to turn.”
Leroy’s big block Chevy also boasts two Aeromotive fuel pumps – a 3.5-gpm pump for the street and a 10-gpm pump for the race system. According to Leroy, that’s enough fuel for 5,000 horsepower on gasoline.
“I designed the fuel injection system using an Edelbrock manifold that has eight injectors, and I’ve got a second set of eight injectors on top that I actually use to cool the air coming out of the supercharger,” he says. “That’s why you don’t see a charge air cooler – we use Mother Nature for all that.”
When Leroy was going about figuring out the cooling system, he knew he didn’t want a radiator in front, but a couple companies turned him down when he was trying to find an alternative solution, until he called Ron Davis Radiators.
“I sent him my sketch and told him what I was trying to do,” Edwards recalls. “They turned it into a blueprint and it looked perfect, so Ron Davis made the cooling system. We also have guards around the radiators, which was something Ron suggested I have. On a hot day going down the road, it runs 170-175 degrees. My oil cooler is in my coolant loop – it’s liquid to liquid – which is from Fluidyne. The car stays cool, even driving for many hours.”
Another aspect of the hot rod that’s had to miss are the wings in both the front (36”) and back (48”). Those were made by S&W Race Cars. Since Leroy was still testing the car and getting it broken in, he wasn’t actually competing in Sick Week this year, but rather getting his feet wet in drag-and-drive as part of the Sick Ward.
“The car is built to run in the Unlimited class, and the big dogs are running into the high-5s,” Edwards points out. “The record is 5.99 – I’ve got to beat it – it’s that simple. If I can’t beat them, I can’t win, and you don’t want to go to a gunfight with a knife now, would you?”
Engine of the Week is sponsored by PennGrade1, Elring – Das Original and NPW Companies. If you have an engine you’d like to highlight in this series, please email Engine Builder Editor Greg Jones at [email protected].
