Porsche aficionados tend to look at their vintage sports car as sacred cows that should be as closely preserved to their original form as possible, but Sean Thomas of Red Bluff isn’t your typical Porsche owner.

“Growing up my dad had a bunch of Porsche 914s that had Chevy small-block swaps,” he explains. “We built quite a few of them over the years and this was one of the last ones. I bought it off of him; I’ve just always been in love with this car. Back in the old days nobody could really afford an all-aluminum small-block, but it basically comes with the package with a lot of the LS engines that are floating around out there now. So about five years ago I decided to put a new twist on the car and swapped it over. It’s really not that hard to do – there are companies out there that sell kits which allow you to bolt them right in.”

Motivating the mid-engine Porsche is a LS3-based V8 with Mamo cylinder heads, a solid roller cam and “all the good stuff,” says Thomas. The combination is good for 589 horsepower, which makes its way to the rear wheels via a five-speed transaxle from ZF. “It’s basically the same gearbox they used in the Panteras and original GT40s,” he notes. “It’s tough to find a gearbox for a mid-engine car that can handle the torque – the Porsche stuff just won’t hold up.”

On the chassis and suspension front, the 914 scored front end components from a 935-generation Porsche 911 as well as a set of coilovers from Elephant Racing, the latter of which are double adjustable at the rear. “We run a sway bar in the front, but nothing in back,” he tells us. “We’ve played around with running and not running one over the past few years, but ultimately it just doesn’t really seem to help.” Momo seats keep Thomas and any would-be passengers firmly in place during high-speed lateral maneuvers, while the roll cage that Thomas and his father installed enhances the car’s safety as well as its structural rigidity.

As it turns out the LS3 isn’t the first LS to have made its way in this 914’s engine bay. “For a couple of years it had an LS1 with some bolt-ons, and it was all this car ever needed – I just got bored and tore into this LS3 project for the past year and a half. When I re-did the car five years ago my intention was to dial it in for Optima-style track events. I wanted something that would be able to do it all, and it almost feels like cheating because it’s so light.”