It’s been a while since we’ve had an update on Tom Tharp’s Project Thunderbolt LS3 Miata build. Since finishing the car back in June, Tharp has been racking up the miles to break in the Miata’s Chevrolet Performance LS376/525 crate engine. This included a trip through the world famous “Tail of The Dragon” in Deals Gap, NC, which boasts an eye-crossing 318 curves in 11 miles.
During the break-in process, the Miata was subjected to a variety of harsh conditions—humid 100-plus degree days, heavy rainstorms, and long periods of idling while stuck in traffic—and we’re happy to report no problems. This is a testament to the high quality components that Tom used to build this little monster.
When the break-in process was completed, it was time for some testing. First up was the chassis dyno at High Velocity Motorsports (Nashville, Tennessee) where the Miata spun the rollers to the tune of 433 horsepower and 411 ft.-lbs. of torque. That’s a lot of fun in a 2,700 pound car.
Tharp then did some acceleration testing with a VBOX GPS-based accelerometer. Even with an easy launch, he recorded a 0-60 time of 4.1 seconds, and VBOX calculated an eighth-mile time of 7.68 seconds at 100 miles-per-hour and a quarter-mile time of 11.59 seconds at 130 miles-per-hour. That makes the Miata one heck of sleeper at the drags.
To see how accurate the VBOX calculations were, Tharp outfitted the Miata with a set Hoosier DOT Drag Radials and headed to his local eighth-mile drag strip. Launching easy and shifting slowly to make sure he didn’t miss a gear, Tharp recorded a the result best pass of 7.76 seconds at 97 miles-per-hour. That’s just a tenth slower and three miles-per-hour less than the VBOX estimates.
What these tests confirm is what Tharp hoped to achieve: that Project Thunderbolt is a very well rounded combination. It isn’t finicky and doesn’t require special conditions to perform well. It just does whatever he asks it to, whenever he needs it. The Miata will happily tool around on date night with the wife in air conditioned comfort, but drop that hammer and things get serious in a hurry.
Check out the video below for more details: