Video: Stock ZR1 Yanks the Wheels, Runs Mid-10′s on Drag Radials
That’s right. This video we found on YouTube features a completely stock ZR1 that’s only upgrade is a set of Mickey Thompson drag radials that lays down a string of mid-10 second quarter mile passes at Maryland International Raceway. But probably the coolest thing about this video is that the ZR1 hooks hard enough off the line on several runs that it actually manages to put some air between the black top and the bottom of its front tires.
We spoke with the driver of the ZR1; the renowned “Fartpipe”, to get the details of his hoop-hanging antics at MIR. Mr. Fartpipe is actually Bruce Keith who hails from York, Pennsylvania. We’re sure that you’ll agree with us that his driving is anything but stinky, even though this was his first trip to the strip with his ZR1. Keith tells us, “Honestly, this was the first time I was able to even floor the car. I bought the car in mid-January 2012, and the day I took the car home I gave the car a little more than half throttle on cold run-flat tires with salty roads. Needless to say, it was a bad combination. The car slid sideways on the highway, and the “Nannies” kicked in and put the car back straight. I thought to myself ‘Ok, that was dumb’. The car almost didn’t even seem like fun to me because the tires would spin so easily. Then I took it to the track Saturday, February 18th 2012. That day changed my mind very quickly.”
Even though this was his first trip to the drag strip with the ZR1, Keith actually has lots of experience racing late model Corvettes. Keith has owned a heads-and-cam C5 that he took into the high 10’s, and a C6 Z06 that we’ve actually featured before on the site. Keith’s time of 10.34 at 134 in his Atomic Orange Z06 still stands as the 3rd fastest time for a bolt-on-only C6 Z06 registered on Corvette Forums.
As we mentioned before, the only modification done to Keith’s ZR1 during the passes in the video was bolting on a set of 315/30/18 Mickey Thompson Drag Radials. Keith says, “That particular tire is one of the shortest 18 inch drag radials that can offer traction to the C6 ZR1. Using the shorter tire helps the car get out of the hole quicker, and results in better 60-foot times with the ZR1′s tall 2.29 1st gear ratio. The overall gear ratio reduction with the shorter tires also helps in reducing heat and abuse to the stock C6ZR1 twin disc clutch. Because replacing a clutch on the C6 ZR1 is a chore to say the least, prolonging the clutch’s life should be important to any ZR1 driver.”
Keith adds, “Tire pressures for these runs were set at 20 PSI warm. I find that measuring your tire pressure before and immediately after the run can be a key to finding the right amount of traction or getting just enough tire spin to achieve your best ET’s.”
A lot of the responsibility for hooking this well with a stock ZR1 falls on the tires, but the driver also has to do his part. Keith filled us in on his launch technique, and told us, “I brought the RPM’s up to almost 5000 and as I’m watching the tach rise, I started to engage the clutch. When I felt the car start to move forward I would roll into the throttle quickly. Getting the car to full throttle quickly was very important to keep the inertia moving forward to get maximum acceleration. I was working to find that very small window where the car will pull hard out of the hole without bogging or spinning.”
So what about the runs where the front tires lifted? Keith tells us, “The car actually lifted the wheels 3 times during my 7 passes. On my 2nd pass I felt the steering wheel jolt real lightly on the launch. I came back to the pits after running a 10.50 at 133 MPH with a 1.58 60-foot, and everyone was excited about the pass. I said, ‘I think the wheels came up a tad on that launch.’ and several people looked at me like I must have ate some paint chips before coming to the track. But a few friends that were at the line told me they thought I got them off the ground. So I made a few more runs learning the car and thinking to myself how the car should sound, how it should feel, and what I wanted the car to do. I tried launching slightly more aggressive and cut a better 60-foot of 1.56, and this was the launch with the picture of both front 19in stock wheels clearly off the ground, dangling there for everyone to see just what the stock C6ZR1 has to offer.”
Keith leaves us with these thoughts on jerking the front wheels in the ZR1; “I have to admit that it happened because I was too aggressive coming off the clutch, and not on the throttle fast enough. This led to a slight bog, and the car only ran a 10.51@133. I knew after that pass I needed to be slower at releasing the clutch and slightly quicker on the throttle. The wheels seemed to come up for couple reasons. For one, the magnetic ride control slows the flow of fluid from the front shocks when the suspension starts to unload, and doesn’t let the wheels come down as fast as other corvettes. The rear shocks also start to stiffen up, giving more traction. It’s a small window, but it’s there! It sure looks cool as heck, but as an old drag racer once told me, ‘If you’re going up, you’re not going out’.”