Ranger's DVD is coming. It's in post-production and scheduled for release via this site in 2010.

Massimiliano's music will be featured on the DVD.

Request to be notified when the DVD is shipping. Click here.

Audio of Ranger's 10.85 pass, then current record for a stock Corvette on drag radial. Listen here.

2009 ZR1 Bone Stock on Drag Radials
10.98 131.87

Here is the video of my back-to-back 10-second passes on drag radials.

My original report on this pass on April 11, 2009

Tuners have been busy modding ZR1s and getting them to the track. But, like many of you, I’m interested in witnessing what owners of these extraordinary cars can do with them in the quarter-mile bone-stock (that is, without modification). To me, as always, it just didn’t seem the car magazine road tests results had done the car justice.

So we developed a plan. Two adventuresome ZR1 owners stepped forward and responded to a post I made offering a rental venue at Maryland International Raceway (MIR) to help them figure out their cars.

On Wednesday, April 8th
ZO6Jeff and zosix427 brought their beautiful cyber gray 2009 ZR1s to MIR for a day of learning and camaraderie. Both cars are bone-stock.

In seven hours three drivers made a total of 45 passes in the cars. Hard-driven hot-laps of two or three passes was the routine. And through all that, neither car broke nor sustained track incidents. Both cars were run in
Traction System Off, one click of the console button. The suspensions were set to Tour. Both started the day with fuel at more than half-tank and heat-soaked from the long drive to MIR. And no sustained cool-down was permitted either car during the day.

Drivers included:
• ZO6Jeff’s son, CF member racerns, made 18 passes, his first in the ZR1. He’s a road racer and auto-crosser with limited drag racing experience in a C6 Z06, a modified six-speed Camaro and a Pontiac G8-GT
zosix427 made 16 Passes and had a previous 10 in his ZR1. He has been drag racing Corvettes for many years.
Ranger made 11 passes, my first ones driving a ZR1. I’ve raced Z06s before.

Track Conditions
The weather was generally favorable. Density Altitude ranged from zero feet at 10 a.m. to +600 from 2 p.m. onward. The Station Pressure was 29.55 to 29.60 (at 80 feet altitude). Dew Point was about 25 degrees. Air Temperature ranged from mid-50s to mid-60s at air-inlet height. Winds were not a notable factor. Track surface temperature was above 60 degrees in the morning and reached 80 by early afternoon.

Track surface preparation was very good. But the first 100’ of the racing surface received its weekly scraping that morning, eliminating the rubber that had formed the racing groove during the previous week’s race days. Jason Miller, the MIR operations director, did the track prep for us and mitigated the absence of an established groove. I must say Jason maintains the racing surface with the care and attention of a marine biologist nurturing a coral reef.

My best of eight passes on stock tires was 1.90 11.21 130.45 and of three passes on drag radials was 10.98 which I ran twice back-to-back with trap speeds of 130.97 and 131.87. My 60’ on DRs were modest, 1.76 and 1.78. In light of my guest-driver status, I felt an duty to go particularly easy on the clutch. So I made fast, clean clutch releases, followed by a graduated throttle squeeze. The other two drivers experimented more aggressively with the clutch, with better results. My trap speeds were mostly above 130. That came from shift-point correctness.

My Impressions of the ZR1 on the Drag Strip
A fabulous car, that’s hard to drive well for max acceleration. That’s why the car magazines haven’t shined with it. The torque of the motor is huge, presenting a challenge to avoid excessive wheel-spin. The solution involves heated tires and a progressive throttle-squeeze in first gear. But loss of momentum via bog has disproportionate, adverse impact on the 60’, 330’ and ET. GM set the ZR1 first gear ratio at 2.29 vice the Z06’s 2.66. That difference looms large in making torque at launch somewhat more manageable and allows the ZR1 to reach 67 before the shift. But it penalizes a loss of momentum more in the ZR1 than in the Z06.

The car has a different rpm-making rhythm than the Z06; its rev limiter is at 6600 vice 7120. So a driver transitioning from the Z06 needs to eye the tachometer earlier than the engine-sound indicates. Clipping the limiters extracts an ET penalty. Slamming the limiter drop the car’s nose and kills the ET.

The ZR1 transmission is a pleasure and shifts positively with little fanfare. Perfect. As always, proper hand position is still a must.

The clutch engagement point is in the top-third of travel rather than the middle-third on other Corvettes. That requires getting used to.

On ZO6Jeff’s car we changed the clutch fluid in the reservoir (three swaps) after pass #10 as a prophylactic. It was seriously nasty from infused clutch dust after starting the day perfectly clean. We repeated the three-swaps at pass #20 before mounting the drag radials. Again it had turned very nasty; but three swaps did the trick.

I was very impressed with how stable and planted the car was under max acceleration. If you replay the video of the two 10-second passes, note how straight and true the ZR1 remained with only minimal movement on transitions. It behaved the same way for me on stock tires. I like that. It quickly gave me confidence going down the track.

Finally I was impressed by the robustness of the car under hard running. Nothing broke; nothing felt weak. I had no wheel hop in my 11 passes. The clutches held up. But they do produce smoke through the center tunnel exit when intentionally slipped excessively. But unlike the LS7 clutch, the LS9 dual-disc did not glaze even once. I am happy to see GM has resolved that annoying issue.

Now that I’ve driven both the ZR1 and the Z06 on the same day at the same track, which car is faster? The ZR1 for sure. It feels faster. It is faster. But it’s harder to launch without a loss of momentum. Still, post-launch, the very wide flat power-band of the ZR1 is unforgettable. And of course the exhaust note at full song, sounds like a genuine race-car. Sweet is an understatement. Just re-watch my 10-second-passes in HD widescreen with the volume cranked. That exhaust note is mesmerizing. It's like you are there.

On my DR passes, a slightly more aggressive launch would have put the car into the 10.8s at a 600’ DA. I suspect some owner will get a ZR1 into the 10.60s on DR and the 10.8s on stock tires. racerns came very close to 10s on stock tires and would have been there with better shifts or the same DA we has at the start of the day or in a car not thoroughly heat-soaked from a long drive to MIR and so many passes.

I must note that zosix427 drove seven hours to reach MIR; made 16 passes; and then drove seven hours home to honor business commitments at first-light the next morning. He’s a true car guy and racer who’s already done the driver-mod and wants to improve even further. He set a series of PRs in his ZR1 at MIR and will be knocking on tens in the fall with more seat-time. I forgot to mention to him (but will here) that as I was preparing to do a burnout on a pass in his car, On-Star called with a status report. I showed “mature judgment” in ringing off that call before spinning the rear tires to copious smoke. That was but a small token in return for the opportunity to make three passes in his ZR1.

I extend once again my thanks to ZO6Jeff for the opportunity to join his son racerns in help wring out the ZR1. I know they will continue to drive the car in the full spirit in which GM unleashed it on the Corvette Faithful…often and at various racing venues.

Also want to thank Chris for shooting the 62 videos of our activities at the event. Great job once again, Chris.

Thanks, as always, go to Massimiliano for the use of his music.