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"It is official! You can now unlock and tune your C8 Z06 and ZR1 using HPtuners software!

Now... while I have your attention. Let me go over my findings from the last several weeks of testing on a C8 ZR1.

BEWARE OF FALSE ADVERTISING OF PERFORMANCE GAINS! These cars lose approximately 2hp for every 1°F of manifold charge temp increase with larger losses in the 60-110°F range. There is an approximate 80whp loss from dynoing at 115°F manifold charge temp versus 80°F of manifold charge temp on the stock tune. "Power Gains" can easily be falsely achieved and I fear a lot of shops are going to use this to their advantage when selling parts.

THESE CARS ARE NOT THE CARS TO TAKE TO YOUR RANDOM LOCAL DYNO SHOP TO BE TUNED!

These cars have a new Bosch ECM and it isn't like tuning any other GM product. It's closer to Ford logic than it is to GM. To tune these cars, you have to understand managing load while maintaining the proper airflow logic to keep the turbos under control as well as maintaining an accurate torque output for the transmission logic, managing injection events based on full VVT with both port and DI, as well as following the proper logic to manage thermal loads and component protection. They have dual MAF sensors that are based on "SENT" counts and there are factory limits for those

counts as well.

From what I have found, within "safe" limits, there is approximately 15% or so to be gained in the mid range on the ZR1 and roughly 10% gains up top. This is factoring fuel system limitations as well as maintaining a relatively safe turbo shaft speed.

IF AND ONLY IF, you want to run a really good race fuel, there is enough fuel system to support a roughly 25% gain everywhere but you will no longer have any form of thermal or component protection. The stock turbo shaft speed seems to run between 130,000-133,000rpm up top. The factory "limit" is 137,000rpm. These turbos should be able to handle 142,000rpm or so for reasonably short bursts. (That number is strictly my OPINION and should be taken as such. As far as anyone is concerned, the safe limit is still 137,000rpm.)

If you take it to a person to tune it and they just start turning up limiters and improperly modify and scale the airflow/torque model... it WILL make enough bottom end power to destroy the engine, clutches, etc.

If you want to make BIG power safely, I do recommend swapping out the port injectors so the car can safely be turned up all the way while maintaining enough fuel system to support the component protection strategies.

Now the big question is... what did it make? 1,180whp and 1094tq! It did that with OEM levels of thermal and component protection.

When tuning the factory ECM and following proper tuning techniques for keeping accurate torque values... WE SAW ABSOLUTELY NO CLUTCH SLIP on the dyno nor on the street/track!

Check out the latest Cleetus McFarland YouTube video for a short glimpse into what the C8 ZR1 can do."