The effect appeared to be most prominent on the Chevrolet Camaro ZL1 machines. At first, it seemed that the coloring was simply paint. In particular, some commentators announcing the Duel qualifying races noted that the No. 50 Camaro of Kaz Grala appeared to have exhaust ports colored pink to match his multicolor livery. However, as the race wore on, other race cars – such as the No. 9 Camaro of Chase Elliott and the No. 5 Camaro of Kyle Larson – exhibited the same exhaust port glow.
GM Authority Executive Editor, Alex Luft, spoke to Chevrolet Motorsports representatives at the Daytona 500 qualifying races to find out more.
“The orange color is due to the heat from the exhaust system causing the material to ‘glow’ in the visible light spectrum,” they said. “Sporadically, ‘fire’ will be expelled from the exhaust outlet due to unburned fuel igniting in the exhaust system. Normally fuel is ignited in the combustion chamber but under certain circumstances, unburned fuel will escape the combustion chamber and will ignite when making contact with the hot exhaust piping.”
The eye-catching exhaust glow in the Nascar Next Gen car could be attributed to changes made to the exhaust paths during its development. Initial tests of the all-new race car demonstrated a concerning amount of heat buildup in the driver’s cockpit, so changes were made to address the issue. One of the updates involved shortening the exhaust pipes so they exit behind the front wheels instead of in front of the rear wheels as originally designed. This alteration minimizes exhaust heat in the floorboards and has helped keep the interiors cool during racing conditions.
It’s not clear why the Chevy Camaros’ exhaust glowed more noticeably than the Ford Mustangs and Toyota Camrys in the field at Daytona, but it will certainly be interesting to keep an eye on the effect as the Nascar season continues.