Road racing is a labor of love. Hard work, dedication, time, and money are all part of the equation, no matter how big or small the scope might be. If you want to be competitive, you will also need to add an excellent skill set for driving and a reliable racing platform. If you’re going to be ambitious and race in Optima Battery’s Ultimate Street Car Association (USCA), that’s another can of worms. One driver that has his program together is USCA competitor, Jake Rozelle.
Photos by: Ashton Robinson
Rozelle grew up riding dirt bikes with his family and quickly transitioned to desert racing at a young age. Rozelle said, “Even before I had my driver’s license, I was obsessed with cars and particularly, in building them. I have been autocrossing and road racing cars since I was 16 years old, when I left motorcycles behind. I have raced wheel-to-wheel and time attack, with wins in both; however, Optima’s USCA series has been my primary focus since it began.”
In 2016, Rozelle purchased his C5 Z06 as a daily driver and for the occasional autocross/road course practice car. He said, “I wanted to keep my skill set sharp whenever we needed to give the Camaro a break.” After owning the car for a year, the modifications on the Z06 had started to pile up. The Corvette was upgraded with Delrin bushings, JRI coilovers, 315mm wide tires on all four corners, Van Steel sway bars, fixed-back Sparco seats, harness, and track alignment. “I loved daily-driving the car, but as always, I wanted to go a little faster. To do so, I knew it was time to pull it apart and take it to the next level,” Rozelle explained.
In 2017 Rozelle teamed up with Lingenfelter Performance Engineering (LPE) and dropped in a built LS7 between the Corvette’s fenders. He also made several other changes to the car in preparation for the USCA series; the new mods included flared fenders, fiberglass nose, custom splitter, ducting, billet LG Motorsports drop spindles, flocked dash and door panels, touch screen entertainment system with backup camera, a C6 ZR1 close-ratio transmission and a whole lot more.
Like most of us, Rozelle loves working on cars. “Building cars is my passion, and you can find me tinkering on this car more nights than not,” Rozelle says.
In a field of highly competitive cars, Rozelle has a new weapon in his arsenal that won’t be a secret very long. For the 2020 season, Rozelle took his Z06 to all three of Optima’s USCA races and won each event. The secret is the addition of a Lingenfelter Eliminator series engine to the C5 Corvette.
Since there’s not much information on the internet yet regarding Lingenfelter’s new Eliminator program, we reached out to Mark Rapson, COO/VP Of Operations for Lingenfelter Performance Engineering, to get the scoop. Mark said, “The Eliminator Series products are our ultimate performance brand when it comes to our performance parts line at Lingenfelter. This engine was derived from customer’s requests for a high-horsepower, naturally-aspirated engine. For this engine, we worked with a lot of manufacturers to build specific components to up the ante on horsepower and not diminish the durability of the powerplant.”
Lingenfelter wanted to stay away from exotic engine blocks and heads, which would drive up the cost of the Eliminator engine. And while this engine may start with a cast GM product, they are heavily modified for durability, eliminating any of the shortcomings these OEM parts might have.
The main concern for this project was the factory GM cast LS7 block itself. Since the units were mass-produced, like any engine, they’re susceptible to small imperfections that typically go unnoticed on a production engine. However, when you start asking more of it than it is designed for, this will compound the problem. And the LS7 block is infamous for having issues with the sleeves.
To cure the LS7 ailments, Rapson reached out to a sleeving manufacturer to fortify the block and cylinders.
“Our sleeving partner took us into another realm of sleeves outside the automotive aftermarket,” Rapson explained. “We worked with them on the top part of the sleeve, or “hat”, on not only the design but also the materials, size, and how it fits into the block. All of the changes to the sleeve became an intricate part of the rigidity of the engine.”
Core shift is also a problem in any production engine, and Lingenfelter uses a CNC machine to blueprint the LS7 cores and realign the bore centers to the crank journals. It then CNC’s out all of the lifter bores while recentering those to the cam profiles with bronze bushings, which adds the proper clearance and stability.
While all of this treatment to the block is extensive, is it needed?
By increasing the rigidity and keeping the cylinders round, the block alone is good for 30 additional horsepower over a factory cast unit. Anytime you can keep the cylinders from distorting, you will have a better ring seal, which is why this block makes more power, – Mark Rapson, Lingenfelter Performance
With the factory LS7 block modified and up to LPE’s standards, it was time to address the rest of the engine. The company turned to new technological improvements where it could. Rapson states, “We looked at newer technology, with camshaft profiles, cylinder head design, intake manifolds, and all of the areas that have been the same design for years.”
Over the years, stronger, more robust parts often come with added weight. Added mass is what Lingenfelter wanted to avoid since the engine would need to turn 8,000 to 8,500 rpm. “We spent a lot of time looking at different piston/connection rod configurations and then testing them,” Rapson explained.
After the engineers were happy with the rotating assembly, which was tested over a year and a half, the focus was shifted to camshaft and heads. This method worked well for LPE, as it was able to create some outstanding results. Rapson said, “The camshaft design offers significantly less lift than any of our ultra-high-performance camshafts, but they make 100 horsepower more and ridiculous amounts of torque at low RPM.”
Two things need to be noted of the Eliminator engine package. First, before you get excited and try to order an Eliminator series camshaft, please note that Lingenfelter only offers it with its engine package. Rapson assured us that while the camshaft works great, it’s not the “goldenrod” for all engines. Every component of this package is engineered to work with other select parts. Secondly, the Eliminator engine is available in a variety of displacements; LPE used the 427 for testing purposes with a 4.00-inch stroke and 4.125-inch bore, but it is willing to build to whatever specifications you want.
Now that we know what goes into each of these engines, what does that equate to on the track? Rozelle has been with Lingenfelter since 2017, and according to him, the new combination has been a game-changer.
“The Lingenfelter Eliminator powerplant is a tremendous boost to my program. Not only does it make incredible power, but the RPM range we run in that motor is a massive help. I no longer worry about changing gears as often as most since I always have plenty of power available,” Rozelle says “Another critical point to note is the engine’s drivability. Making significant power is essential, but it’s useless if you can’t put it to the ground. Lingenfelter did a great job making the Eliminator power delivery smooth and predictable so you can get every drop of performance out of it. Being naturally-aspirated not only enhances the joy of driving it, but also keeps everything reliable and straightforward, which is incredibly important when building a car for the track.”
Usually, when you add an engine with a lot of RPM and power, you need to make some changes to chassis so that the car can work to its fullest. While Rozelle’s Z06 was already highly modified, a few changes were made to accommodate the Eliminator. The first thing to get modified was the torque tube. The OEM couplers were switched out to solid units to avoid breakage from the added torque. Secondly, due to the high-rise intake, the hood had to be cut for clearance. Finally, the Z06 received fender flares to widen the stance, increasing the mechanical cornering grip.
I love it! The engine offers fantastic driveability, reliability, and sounds absolutely incredible. I just change the oil every couple of events and keep running it! – Jake Rozelle
It’s funny to think that Rozelle’s killer Z06 started off as a daily driver and is now dominating the USCA. It just goes to show that hard work, dedication, and the right combination of parts, can work wonders for any racing program. With the LPE Eliminator engine nestled in the Z06 and Rozelle behind the wheel, he might be unstoppable in 2020.