Tuners Finally Unlock the C8 Corvette ZR1's ECM and Find Nearly 1200 HP

• A new ECM upgrade from HP Tuners unlocks tunability for the C8-generation Chevy Corvette Z06 and ZR1 engines.
• A tuned Corvette ZR1 put down a claimed 1180 horsepower to the wheels, as first revealed by a post on Corvette Blogger.
• All in, the tune runs about $2000, which is relatively inexpensive for those numbers.

If you just can't wait for the hybrid all-wheel-drive Corvette ZR1X to arrive and need more power than the stock ZR1 makes—a mere 1064 horsepower—then a new ECM upgrade from HP Tuners may be in your future. The speciality tuning shop appears to be the first to get inside the new engine control modules used on the Z06's LT6 and the ZR1's LT7 V-8s. Dyno testing shows the twin-turbo LT7 is good for nearly 1200 horsepower at the wheels with the right mods.

In a lengthy Facebook post, Matt Sanford of HP Tuners explains that the tune should increase output by about 15 percent in the middle of the rev range and 10 percent at the top on a ZR1 without doing anything that's going to cause heat or durability issues. Those hungry for more power—and with less mechanical sympathy—should be able to eke out a 25 percent increase by his estimation, with one of the limiting factors being GM's cap on the stock turbos' shaft speed (137,000 rpm, if you're curious).

Sanford doesn't mention any output figures for the Z06's naturally aspirated LT6 engine post-tune, but a ZR1 with massaged code hit 1180 horsepower and 1094 pound-feet of torque at the wheels. (The car in question was fitted with exhaust downpipes and was running on 109-octane race fuel for the dyno test.) While those gains aren't nothing, it's worth noting that even stock ZR1's have been shown to make more than 1000 horsepower at the wheels, as Hennessey Performance documented in this YouTube video.

Tuning is definitely an art, but gaining access to the ECM's code requires some clever computer science. Sanford says Chevy is using a Bosch ECM for these engines (the Corvette Stingray uses a different computer altogether) that works more like what he's seen on Ford engines than those from the General. All of that had to be reverse-engineered before they could mess with the factory tune.

This isn't a simple reflash you can do with a laptop in your garage, at least not immediately. The upgrade requires temporarily setting your C8 Vette to zero horsepower; the ECU has to be removed and sent to HP Tuners for surgery. Once the computer is reinstalled, the owner can play with calibration, logging, and scanning via HP Tuners' MPVI4 OBD-II interface and VCM Suite software using a Windows computer. (This setup is new enough that you have to use a beta version of the software, so the technically skittish may want to wait until it moves to the stable release.)

The ECM upgrade costs $1499, and then you have to buy 10 "Universal Credits" (think of them like tuning tokens) at $49.99 each to download the new code. So, all in, you're looking at about $2000 for access to a healthy dose of extra power. Now just think what they'll be able to do with that 1250-hp ZR1X.

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David Gluckman

Contributing Editor

Ever since David was a wee Car and Driver intern, he has kept a spreadsheet listing all the vehicles he’s driven and tested. David really likes spreadsheets. He can parallel-park a school bus and once drove a Lincoln Town Car 63 mph in reverse. After taking a break from journalism to work on autonomous vehicles, he’s back writing for this and other automotive publications. When David’s not searching for the perfect used car, you can find him sampling the latest in gimmicky, limited-edition foodstuffs.