Mini-Feature: Ryan Lusk’s Cummins-Swapped 1968 Corvette


No one is quite sure where it began, but once it did, it became an automotive tradition as celebrated as barn finds or Barrett-Jackson: Cummins swaps. Taking these large, six-cylinder mills and posing the question of, “Will it fit?” became a challenge for many, and among those that succeeded was Ryan Lusk of Mitchellville, Iowa.

“I’ve always loved old cars, trucks, tractors, planes, pretty much anything with wheels,” said Ryan. “During my childhood, my dad and I were always helping Uncle Jerry work on a hot rod. I segued into diesels in high school, buying first a 1989 F-250 with the 7.3-liter IDI, and then a 1994 Dodge Ram with the 12-valve 5.9-liter Cummins.”


Ryan cycled through a couple more trucks following that period (they were 6.0-liter Power Strokes, which Ryan got tired of) and then built a 1992 F-350 4×4 with a 5.9-liter Cummins. With his interest piqued, Ryan chose to make diesel his life and became a diesel technician. “Things have just snowballed from there,” he commented.

Around 2005, Ryan became interested in having his own Corvette after seeing a buddy’s collection of them. “He worked up a scheme to trade me a wrecked ’68 coupe for my 1972 RS Camaro, a car I’d owned and built up since 2000,” said Ryan. “I made the deal, even though the car was very rough. It had been rear ended and declared a total loss. Fortunately, it came with a rebuilt front suspension and a narrowed Ford 9-inch, Weld Racing wheels, and the seller was supposed to help me fix the frame.”

The Corvette with its first paint job, circa 2010. The fastest it's ever traveled has been 133 miles per hour, finishing a pass at just 11.32 seconds!

Taking a cue from Johnny Cash, the Corvette began to take on a “One Piece At A Time” style. “There were a few different years of parts on this car,” Ryan explained. “But it didn’t matter to me, as I had always wanted a chrome bumper Corvette. So I built one that suited me and showed what I love to do.”


Ryan initially had the Corvette equipped with a rational drivetrain ensemble – a 396 V8 and TH400 transmission, sourced from a Camaro. That all changed when Ryan had a get-together at his shop with diesel buddies of his.

“I had just finished a 5.9-liter Cummins conversion in my Dad’s 1991 F-350,” Ryan recalled. “Guys were standing around it, talking about it, and my Dad came up with this plan of how I shpuld just put a Cummins in hte Corvette, since I had been swapping htem into trucks anyhow. At first, I was in the same boat as the two guys saying it could never be done. But the more my Dad talked about proving those guys wrong, the better it sounded.”

Eager to prove to himself and his friends that he could do it, Ryan took on the challenge of removing the 396 ci BBC and TH400 he had already installed, and swapping in a Cummins 12-valve straight six and a four-speed A-518 automatic transmission. He finished in 2009 and made an appearance at the TS Performance Outlaw Diesel Drags that same year.


It was 2007 when Ryan began actively installing the Cummins into the Corvette. Finished by 2009, he got the car out to the TS Performance Outlaw Diesel Drags that year. Off the track, the Vette has more charm and attention than Zsa Zsa Gabor.

“I love the reaction I get from people driving by,” said Ryan. “Diesel people have an idea what just went by, but most people are baffled and the responses range from outrage to loving every part of it.”


Regarding future plans, Ryan hope to cut out some weight in the Corvette, as well as try out racing slicks (up to now, he’s only used DOT drag slicks).

Plans for the Corvette are in the works, starting with a set of slicks. “I’m also going to try to put the intercooler over the engine and get the weight out in front of the front wheels, and eliminate some piping,” said Ryan. “A lighter battery, a smaller fuel cell, and some other weight savings, too.”

Unfortunately, the C3 has been bench racing for the better part of two years due to life getting in the way. Still, with its all-time high of 11.32 seconds at 133 mph, the car has proven itself as a racing application, and will probably see action again someday.

About the author

David Chick

David Chick comes to us ready for adventure. With passions that span clean and fast Corvettes all the way to down and dirty off-road vehicles (just ask him about his dream Jurassic Park Explorer), David's eclectic tastes lend well to his multiple automotive writing passions.
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