Krista tells us about her drag-and-drive Chevette using the COMPUSHIFT Sport for a 4L60E:
"Hi Rodney - I wanted to take a moment to share our experience with the HGM COMPUSHIFT and thank you for the incredible product and support. The transmission controller worked flawlessly for our application, and we couldn’t be happier with how it performed during Sick Week.
About the Car & Drag-and-Drive Racing
Our car is a 1984 Chevrolet Chevette built for drag-and-drive competition. These events challenge racers to compete at one drag strip and then drive to additional race tracks over five days, covering over 1,000 miles with no support vehicles or trailering. Each route from track to track is specifically mapped by race officials and includes unique checkpoints along the way. Everything we need to keep the car running has to fit in the car or the small tow-behind trailer, and the only people allowed to work on the car are the driver and co-driver.
We recently completed Sick Week, a drag-and-drive event that started in Georgia, traveled to three different drag strips in Florida, and then returned to Georgia to finish the week. This year, we even had the opportunity to drive the Chevette (with the trailer) on Daytona Beach!
The Build
We bought the car in 2019 as an existing race car but completely tore it down to a bare body and rebuilt it during COVID in our two-car garage. It’s powered by a 4.3L V6 from an early ‘90s Silverado with a custom-grind .580” hydraulic roller camshaft, forged pistons, H-beam rods, and a set of ported Vortec heads. It runs a 650 CFM mechanical secondary carburetor with a Nitrous Express nitrous plate. The 4L60E transmission is built with Sonnax hard parts and was assembled by Wendell Dunaway at Mr. Wendell’s Motorsports. Power is transferred through a Circle D Specialties billet lock-up torque converter.
For Sick Week, we ran the car naturally aspirated (no nitrous) and still finished the event with an 11-second quarter-mile average.
Why We Chose COMPUSHIFT
After a lot of research, we opted for the HGM COMPUSHIFT, especially after seeing a unit demoed at a local transmission shop. The Bluetooth app made setup, adjustments, and monitoring incredibly easy. We also purchased HGM’s standalone throttle position sensor for our Holley 4150-series carburetor, and installation was straightforward—hook up a few wires, adjust the TPS, and it was essentially plug-and-play.
Initially, we had some issues with the lockup and shifting. Mike at HGM provided outstanding customer service working with us to troubleshoot the issue. With the transmission on the dyno we were able to isolate the issue to two brand new GM solenoids that were apparently bad right out of the box. Wendell replaced the solenoids, and we were back in business.
Performance on Sick Week
We left for Sick Week with only 150 miles on the new transmission setup. On the first drive from South Georgia Motorsports Park to Bradenton Motorsports Park, we were able to dial in lockup and shift settings on the fly. On the track, we fine-tuned the wide-open throttle shifts while keeping street driving smooth and consistent.
One of our favorite features was the mode button, which allows for full manual shifting at the touch of a button. While this is useful in some situations, we found that the Compushift’s automatic shifts were so precise and consistent on track that we let it handle the shifting completely.
Final Thoughts
We couldn’t be happier with the HGM product and support. Hopefully, you can use parts of this for marketing or a testimonial. If there’s anything we can do to help promote your products, let us know!
This car has drawn a ton of attention, especially now that it’s running a standalone 4L60E with a carbureted engine. We’re discussing the possibility of showcasing the car at PRI at the end of the year, so if that works out, we’ll be sure to keep you in the loop. We also have a YouTube channel where we documented our Sick Week journey. There’s a lot of info on the setup with the car there as well."
