The eco-exotic sports car was built from the ground up with energy efficiency in mind.
The idea came to him while he was in China. Ronn Maxwell, CEO and founder of Ronn Motors and father of the Scorpion and Limited Edition Scorpion HX eco-exotic sports cars, was going to build a sports car in China for a large bus manufacturing client. After his visit in 2007, he found that the project simply proved to be too difficult.
“When I came back to the states, I still had the idea in my head and it wasn’t like this was going to be our first automobile,” Maxwell recalls.
“We’ve been building cars since we were little boys. I figured that now was the time to just design my own automobile and build it from scratch like I had always wanted to do.”
Maxwell didn’t want his car to look like anything else in the market, and he knew exactly what he wanted from conception.
“Being a car builder, you pick up what you like and what you don’t like through the years,” says Maxwell.
“If you look at our car long enough you would probably find components from 20 different cars over the years. There might be some muscle car in there, there might be some Lamborghini, there might be some Corvette, but I like European cars and I was going for that look.”
Aesthetic value was Maxwell’s top priority, which led to the vehicle’s curvaceous body. “I was very strict about how the car looked,” Maxwell notes.
“I wanted the Scorpion to be curvy all over. I didn’t want any angular lines and it was the major design piece. We designed the car as a piece of artwork. I wasn’t overly concerned with the functionality of the car early on, I wanted it to be beautiful first and then we could go back and fix the rest of it.”
Hydrogen Fuel Injection
Ronn Motors built the Scorpion from the ground up with energy efficiency in mind. The car is a mild hybrid with a lightweight hand-built carbon fiber body and a chrome-moly chassis. It is powered by an Acura V-Tech, V-6, Type S, 3.5 Liter power-plant from the 2008 TL TypeS.
An on board hydrogen-on-demand system provides 130 octane hydrogen in real time, blended with gasoline in ratios of 30 to 50 percent. Coupled with a close ratio six-speed transmission and other fuel saving measures, the Scorpion’s highway fuel economy is in the 40 mpg range, and capable of producing 450 horsepower with the twin-turbo option. Maxwell strove towards efficiency from an overall systems approach.
The car is also incredibly aerodynamic with taller wheels to help improve the gear ratios. He handpicked the Acura motor because it was so efficient and lightweight and added proprietary air-conditioning components that reduce horsepower drag on the motor.
“We wanted to make a proof of concept statement with the car, so that’s why we came up with the hydrogen,” Maxwell says. “We looked at hydrogen fuel cell technology, but it’s not something that’s really practical today; maybe two or three years down the road it will be better. We also looked at making it an electric hybrid and that is still a few years from true mass appeal.”
Ronn Motors chose to move forward with real-time hydrogen injection, but once they entered the marketplace and started looking into the technology, they found that many didn't know anything about it.
“Most of the people knew a little bit about the technology, or had read a bunch of stuff on it in the past, but had never built an automobile,” Maxwell says. “They didn’t understand how hydrogen worked in an engine.
They didn’t understand how hydrogen worked in a cylinder. They didn’t know how to make hydrogen work with modern computer controls. This is what we do best; we sat down and figured out how to make it work right.”
The onboard system produces hydrogen during vehicle operation through electrolysis of water using the power generated from the vehicles electrical system. A small amount of hydrogen is added to the vehicles intake air/fuel mixture and allows the engine to operate with less fossil fuel. “It is basically an electrolysis machine,” Maxwell says. “We hate to say that, because it’s much more sophisticated than that.”
Using a computer management component that was designed in-house to control the hydrogen fuel-injection function, the system injects small amounts of fuel into the engine as it’s driving down the road in real time.
“These are not massive amounts,” adds Maxwell. “All we needed was enough hydrogen to inject into the motor to get the benefits. We’re not like the guys who are saying that they can get 100 miles to the gallon and run their engines on 100 percent hydrogen.” Ronn Motors wanted the benefits of using hydrogen as a catalyst, similar to injecting nitrous oxide or something into the motor.
Too Good To Be True
“Of all the cars that I’ve built over the years, this has really been the easiest one,” Maxwell boasts. From notepad to the 2009 SEMA show, it took less than six months to build the car.
The biggest hurdle came from the electronics; the team took nearly a month to figure out how to get the engine to talk to the computer system. “We thought we were pretty smart,” Maxwell says. “We thought this would be a piece of cake, but when you take an Acura engine out of an Acura automobile and you want to use it from scratch it proves otherwise.”
The new electronics on the automobiles, particularly on the emissions side, are sophisticated — as are the anti-theft devices. The new engines, engine control modules and computer controls are not really designed to be taken out of a car, but eventually Maxwell and Co. were able to find a solution.
“Acura actually told us that we now knew more about the engine outside of an Acura automobile than they did,” Maxwell adds.
The Scorpion also includes an Indy car suspension — Maxwell wanted to be able to adjust it in eight different ways in all four corners. He also opted to create a rear-engine design for balance.
Energy Efficiency Systems
The Scorpion’s air-conditioning system features Maxwell’s Pro Cooler, a patented device that he’s been selling for about 16 years, mostly to Porsche owners for their air-conditioning systems. The Pro Cooler is a replacement for the accumulator or receiver/dryer on an air-conditioning system.
It allows the car to run 20 percent less refrigerant in the system, saving horsepower. On a 100 degree day, the Scorpion would probably save about 7½ horsepower, because less refrigerant leads to less head pressures, which translate to less drag on the engine. The refrigerant is also less likely to get into the atmosphere if the car is running 20 percent less.
Maxwell’s design includes refrigerated intercoolers that nobody else in the market is running right now. “Our car is not dependent on outside air to cool the intercoolers,” Maxwell states. “It’s not dependent on water and you don’t have to put the intercooler somewhere in the airstream to block the airflow. By using refrigerated intercoolers, we can also manipulate the temperature we want for the intake so we can actually make it more efficient.”
Translating The Technology
“We’re not doing something that is super exotic,” Maxwell adds about the internal components. The Scorpion’s was intentionally designed to be very practical as a result of one of Maxwell’s pet peeves. “Our car is built very user friendly. You could take our car to any kind of car dealership anywhere and get it worked on. Most of the pieces can be purchased someplace else; we have very few pieces that you have to buy directly from us. It irritates me when, if you drive a Ferrari and it breaks down, you have to find a special wrecker to take it to a special shop and then they have to keep it for four months while they order special parts, I hate that.”
The Scorpion’s surfacing data was done entirely in Rhino. Maxwell worked with a 25-year-old employee on the surfacing data and that was the program he preferred. The data was so good and Maxwell was so confident with the data that he went straight from the computer to cutting a mold, bypassing clay altogether. Maxwell insists that he made the gutsy move because of his faith in his employee.
“He didn’t watch television, he didn’t play games, he had two computer screens and a computer that was powerful enough to glow in the dark, and he would literally sit there and work on that surfacing for hours and days at a time until he got it just right,” Maxwell compliments.
“We had gone over the data, we knew it was going to fit, we gave him the parameters on the chassis – that we designed ourselves – and it fit nearly perfectly when we mounted it to the chassis.” There were a few crash points on the first attempt to mount it to the chassis, but 90 percent of it was a perfect fit. “We made promises and had time constraints, but I don’t recommend this development process to everybody.”
Maxwell didn’t have a reset point throughout the six months; he was going to put everything on this one. Ronn Motors’ long term plan is to make a second car that is a people’s car. Maxwell notes that the concept is already on the drawing board, and he’s ready to build “really cool cars” that are in the $30 to $40 thousand price range so the average person can buy one. The Scorpion is $175 thousand for the low-dollar version, the Scorpion HX, the high-horsepower version is $250 thousand.
Maxwell must have done something right; at SEMA this year he had unexpected fanfare. “When you have officials from Lamborghini and Ferrari coming over to your car and telling you how much prettier it is than theirs, you know you’ve done right.”