The mid-engine Z51 Corvette and the Ford Shelby GT500 are two incredible American sports cars. They both feature fantastic exterior and interior designs as well as impressive performance specifications. The two vehicles were pitted against each other to find out which of the two is faster, and while the GT500 has more power, the answer isn’t as straightforward as you’d expect. So let Engineering Explained, well, explain.
Which is faster; the Z51 or the GT500?
According to Chevrolet, the new mid-engine Z51 Corvette can go from zero to 60 mph in 2.9 seconds. Despite the Ford Mustang GT500 being capable of producing 760 hp, a lot more than the 495 hp of the Z51, it is slower in the zero to 60 mph range. The Ford Shelby GT500 goes from zero to 60 mph in 3.5 seconds.
However, Corvette fans shouldn’t celebrate yet. While the Z51 goes from zero to 60 mph at a shorter time than the GT500, the GT500 beats the Corvette at the zero to 100 mph range. According to Car & Driver, the Ford GT500 can hit zero to 100 mph in 6.7 seconds, compared to 7.6 seconds in the Z51.
This shows that the GT500 is traction limited. This means the car is not able to put down all of its 760 hp below 60 mph but can utilize its superior power at higher speeds fully. But that doesn’t tell the full story.
With the Mustang GT500 horsepower being significantly higher than that of the Z51, how is the Z51 Corvette able to hit 60 mph at a shorter time than the GT500? The video seeks to find the answer by looking at the vehicles’ other parameters and crunching a few numbers.
It would be fair to mention that not all the parameters used are confirmed to be accurate with some of them being estimates and the rest got from various sources.
The Ford GT500’s weight of 4225 lb is more than the 3577 lb of the Corvette. While the Z51 is the lighter of the two sports cars, this is not what makes it the faster of the two in the zero to 60 mph range.
Even if the GT500 is the heavier of the two, the car still has a better power to weight ratio than the Z51. The Mustang GT500 has a power to weight ratio of 5.56 lb/hp compared to the Z51’s 7.23 lb/hp. In terms of the vehicle’s weight distribution, the Z51 has a 40:60 split meaning the rear tires carry 60% of the car’s weight.
On the other hand, the GT500 has a 56:44 split meaning the rear tires only bare 44% of the vehicle’s weight. This is still not necessarily what makes it slower out the gate because a vehicle with that weight distribution and rear-wheel drive could still out-accelerate a vehicle with Z51’s parameters.
The best way to understand the reason is to try and come up with a theoretical limit that each car could accelerate to if they both had infinite power.
Crunching the numbers
Assuming a frictional co-efficient of 1.3 for both tires, the Z51 was found to theoretically be able to accelerate at 0.99 g making the theoretical time the Z51 would take to hit 60 mph, 2.76 seconds. With the Mustang GT500 unable to put more of its weight on its rear tires, its peak acceleration was limited to 0.75 g.
For the Z51, the limiting factor was found to be its reduced power, making it slower at higher speeds. On the other hand, for the Mustang GT500, the limiting factor is its grip.
This explains why the Z51 Corvette is the faster of the two in the zero to 60 mph range but takes longer to hit 100 mph.