Riding shotgun in Corvette's biggest ever weapon
I got a ride in the 755-horsepower Chevrolet Corvette ZR1. Yup! A couple of hot laps around the big track at Willow Springs in the passenger seat with one of Chevy’s factory hot shoes. Neener-neener-neener! Before I tell you what it was like (hint: not bad!), let me address a few points the Corvette team would like you to know as well as a few concerns you all might have.
First and foremost: is it gonna overheat? In case you’re not up to speed, when pushed hard pre-2017 Corvette Z06s heat soaked/overheated. Chevy addressed this by redesigning the Z06’s hood, fitting a different supercharger cover, and upgrading the cooling system. All of the changes are backward compatible, so current Z06s do not overheat and older ones can be fixed. Case closed. However, if the internet has taught us anything, it’s that nothing is as fun nor as satisfying as crying over spilt milk.
As for the ZR1, based on what not only chief of Corvette Tadge Juechter but also small block guru Jordan Lee told us, there’s a better chance of polar ice caps staying in one piece than there is of the LT5 getting too hot. For one thing, they changed their internal certification. Long story short, the car must be able to do whatever the given certification tasks are at 100 degrees. The previous certification temperature was 87 degrees.
Moreover, in addition to the primary radiator there are two auxiliary radiators for the main cooling system. There’s an intercooler and two secondary intercoolers. See the big chipmunk cheeks below the ZR1’s eyes? Each cheek holds two of the auxiliary coolers. There are also two intercoolers just for the supercharger. All in all, the ZR1 packs 12 heat exchangers (13 of ‘em if you get the eight-speed auto). A Bugatti Veyron had 10.
The intercooler itself spins more slowly than the one found on the Z06—around 16,000 rpm versus 21,000 rpm. That keeps things cool. However, the 2.65-liter supercharger (internally nicknamed BAS—see if you can figure out what that stands for) is over 50 percent larger than the one on the Z06. Is the entire aftermarket clamoring to be first to slap on a smaller pulley, thereby increasing the supercharger’s speed and sending power over the moon? Oh yes, absolutely. Lee, however, says doing so will (duh) hurt the LT5’s long-term reliability.
The LT5 also marks the first application of dual fuel delivery on a GM product, both direct and port injection. Basically, if Lee and his team made the DI pump any larger, it would damage the cam lobe that powers it. Lee then admitted that one of the issues with a cam-in-block motor is that you only have so many cam lobes. So to get enough fuel into the cylinders, there’s a secondary port injection fuel rail. Problem solved. Another problem they ran into with the ZR1’s LT5 powerplant is that Lee and his team kept breaking dynamometers. No, really. I think they’re still solving that last one.
One of my big problems with the Z06 is that the rear end of the car cannot handle the 650 lb-ft of torque that the LT4 produces. I will never forget going down the Corkscrew at Mazda Raceway Laguna Seca passenger window first. We’ve complained about this fact over the years, but once you run out of tire in a Z06, good luck! The ZR1 addresses this not only through chassis recalibration but also with aero. At top speed, should you opt for the $2,995 ZTK package, the front underwing and major league rear wing provide about 950 pounds of downforce—that’s about 750 more pounds than the Z06. Does that fix the problem?
Well, from the passenger seat things seemed pretty good. Alex, the Chevy engineer who gave me my laps, blasted out of the pits. Yeah, yeah—it’s quick. But it feels ferocious. Torque plus traction equals go, go, go! Chevy’s claiming 0-60 is less than 3 seconds and the quarter mile is in the high 10s. I have no reason to doubt their claims. One more note: Chevy says the ZR1’s top speed is 212 mph. Interestingly, Corvette chose to go with a two-way average 210.20 mph in one direction and 214.88 mph in the other. Meaning 212.54 mph. At 212.56, they could have called it 213 mph.
As for my laps, it’s tricky to gleam a whole lot from the passenger seat. I’m lucky in that for the last few years I’ve spent a ridiculous amount of time riding shotgun around Big Willow with Randy Pobst at the helm. I’m pretty used to the experience and was perhaps able to look for things other folks might miss. For instance, entry speed into Turn 8 was an indicated 140 mph. Fast, but I’ve seen Randy dip into that corner with a speedo indicating 150-plus mph. Does this tell us anything about the ZR1’s abilities? No, Turn 8 is one of the world’s more insane corners. Alex and I were talking, and he is a very good driver for an engineer, but he ain’t a pro racer.
I can say that while turning right at 140 mph, the rear end of the ZR1 seemed planted and calm. I’ve driven a few different Z06s around that corner (a C6 ZR1, too), and they were anything but what I just described. The ZR1’s retuned magnetic dampers seemed able to handle the notoriously bumper surface that comprises the bulk of Turn 8 into (terrible) Turn 9. The ZR1 seemed calm through 9, as well.
However, I did see 156 mph indicated (I keep saying indicated because speedometers are notoriously optimistic) down the front straight. That’s a big number. Again, I’m an extra 230 pounds of dead weight, Alex and I were talking (meaning he’s not going 10/10ths), and based on what I’ve seen Randy do, he braked early. If the ZR1 can crack into the 160-mph zone on the front straight, it has a decent shot of putting down a lap time in the 1:23 range. Currently, the best lap we’ve ever seen at Big Willow is 1:23.54 set by Randy in a Porsche 918 Spyder. Although, semitruthfully we’ve tested a handful of cars recently that—well, stay tuned.
There you have it. I can’t tell you much. Chevy did tell us they’re launching the mighty Corvette ZR1 in March, and we’ll be able to get our hands on one for testing and a video by late April/early May. Until then, the one thing I can tell you is that the ZR1 sounds glorious. Full throated, burning red, searing white, and blaring blue awesome. Did I mention loud? It’s loud, too. Like insanely, how-can-it-be-legal loud. I dig it. I can’t wait to drive it. Here’s to Chevrolet for having the intestinal fortitude to release such a monster.
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