Dan Ryntz Swapped Two Race Mustangs From Coyote To Godzilla Power

When Dan Ryntz competed in the National Mustang Racers Association, he held his own in Factory Stock, Coyote Stock, Limited Street, and Street Bandit 10.10. He even earned a Factory Stock championship in 2018 and 2019. However, when the series ceased operations at the end of 2024, Ryntz committed to racing at other events, and he has positively picked up the pace.

In his 1989 Mustang coupe named Battle Buddy, the Pennsylvanian won in NMRA Factory Stock at the Holley Ford Fest in 2025 at Beech Bend Raceway in Kentucky, led qualifying for the domestics with a 9.18 and 144 mph in the All-Motor class at the Haltech World Cup Finals — Import Versus Domestic presented by Wiseco at Maryland International Raceway before the race was called due to rain in 2026, and won at Muscle Car Mayhem at South Georgia Motorsports Park in 2026, where he ran 9.64.

These days, his Fox is powered by a Godzilla 7.3-liter engine constructed by Charlie Booze Jr. at Booze Brothers Racing. It is backed by a C4 and relies on UPR suspension to plant the power, with Mickey Thompson Pro Bracket Radials proving the hook. For Factory Stock, Ryntz must add weight and make chassis adjustments to accommodate the weight.

Ryntz also mixes it up in N.A.S.T.Y 9s, a naturally aspirated, small tire heads-up class at Mason Dixon Dragway in Maryland, where he has earned a few wins, most recently on Sept. 19, 2026. He is ready for the Haltech World Cup Finals — Import Versus Domestic presented by Wiseco, November 4-8, 2026 at Maryland International Raceway.

While it might seem like he is too busy with his 1989 Mustang coupe to focus on another car, he also has a 1990 Mustang hatchback, which he purchased three years ago for Pro Stick racing. He raced it in the class for a few months before it broke and went back in the garage.

“I bought the 1990 Mustang hatchback about three years ago, primarily to go Pro Stick racing, and since it was originally set up for an automatic transmission, I had to set it up for a manual transmission with a clutch pedal set-up, and I had to modify some of the tubing because it is a double-frame-rail car,” Ryntz explained. “When I broke the U-joint on the driveshaft a few months into racing the car, I decided to make some other upgrades, so the car has been down for almost two years. We did a lot to it, and got it back running very recently.”

Ryntz enlisted Charlie Booze Jr. to build another Godzilla 7.3-liter engine with higher compression and slightly ported heads, and he moved from a G-Force Transmissions GF5R five-speed to a GF2000 five-speed. He also hired James Smith of JSC Race Cars to fabricate a new 9-inch rearend, and he wired in and programmed a FuelTech FT550 for tuning, datalogging, and gauge display.

To apply that Godzilla power to the track, he selected AFCO shocks and struts under the car that rolls on Weld double beadlock wheels wrapped in 32×14 Mickey Thompson slicks on the back and AlumaStar wheels in the front. When the car was ready, he took it to a test session on Friday, September 4, 2026 at Mason Dixon Dragway.

“Testing for the new build went well,” said Ryntz. “I had copied the tune from my other Mustang, Battle Buddy. I had a bunch of timing pulled out of the launch to control the wheels, but when I used that same tune in the big-tire car, it fell flat on its face because it did not have the power it needed on the launch.”

He went over various scenarios in his head, and by the time he arrived at the Pro Stick race at Beaver Springs Dragway in Pennsylvania the following day, he knew what he wanted to try.

“It took me a minute to realize what was going on, but I figured it out and adjusted the timing, and the car came around,” Ryntz said. “After we figured out the timing issue, we worked on figuring out the rest of the new setup, with the new transmission, new clutch, and bigger tires, and I ran a best of 5.70 at 122 mph in the eighth-mile that weekend. For a new build, I was pretty happy to go out there and run that number.”

That work paid off with a round win at that event with his new combination, but he is confident he can coax more out of it.

“I ran a Coyote engine for many years, and I just wanted to change things up by going to a Godzilla engine,” Ryntz added. “People tell me it has a sound all its own on the top end of the track. It has a nice cam lope. Everything about it is appealing to me.”