Speed addicts and tuning firms from and all over the country make the trek to Beeville twice a year to mash the loud pedal and see who comes away with the fastest speed slips over the course of three days. The Lethal crew couldn’t wait to try out its new road rocket, and were thoughtful enough to invite us along to document the effort. It was an easy call for us, as the majority of production cars entered were Corvettes.
The first runs started at 7:30 a.m., when it was cool enough to make good power. But by noon, the ambient temperature had increased enough that speeds were falling off. The line of cars waiting to run stretched so long that it was impossible to get more than two or three runs each day before hot air took its toll on power. Due to variations in altitude, the humidity and the lack of a two-way run, it’s futile to compare times run at the Texas Mile with those from other tracks.
In his first run on Friday morning, Gonzales was clocked at 195.8 mph through the timing lights. He did no better on his subsequent runs that day. Actually, his times slipped backward, so he decided to wait until the next morning to try again.
Saturday was more of the same. The magic 200 mph remained elusive and the heat was causing problems with the Corvette’s engine control system. Specifically, when the ECU saw intake air temperatures at 140 degrees, it retarded timing to prevent piston damage. When the temp hits 180 degrees the ECU switches to another engine map, retarding timing further and cutting more power. Gonzales tried adding a methanol injection kit to the intake, but it ended up costing power, as the ECU richened the fuel/air system to compensate. His best Saturday run was a 195.7 mph.
Sunday was the last chance to make more speed, and Gonzales and partner Joe Michael Garcia iced down the intercooler in an effort to reduce intake air temperature. They also removed the GM relay that controls the intercooler recirculating pump and rigged a switch to pump cooling fluid through the intercooler with the engine off.
With everything working, the Corvette rocketed to a 197.3 mph—short of the target, but still impressively high. Couple this with the 9.71-second quarter-mile time and you have a ZR1 with some heady stats. Very few ZR1s that have this level of performance are still running the stock supercharger and transmission. And not only is this car still streetable, the upgrades didn’t break the bank. Gonzales estimates it would cost a customer $15K for a similar conversion.
So what’s in store for the silver ZR1? Gonzales is considering adding a recirculating coolant reservoir in the back of the car to drop temps at the intercooler, along with ported heads and a bigger 102-mm throttle body. He thinks upping engine output to 830-850 rear-wheel horsepower would help him break through that pesky 200-mph barrier.