590 WHP on E85: Custom Tuning a 2023 Corvette C8 Z06

By N2Speed Remote Tuning — April 2026

When a customer brought us their 2023 Corvette C8 Z06 loaded with bolt-ons and a switch to E85, we knew this calibration was going to be something special. Here's the full breakdown of the build and what the dyno revealed.

Dyno Results

• 590 wheel horsepower (WHP)
• 408 lb-ft wheel torque

Numbers reflect a single pull on a custom remote calibration.

The Build

This C8 Z06 came to us with a serious list of modifications already in place. The factory 5.5L flat-plane crank V8 is a screamer by nature — but with the right supporting mods and a proper custom tune, the numbers climb fast.

• Long tube headers — Dramatically improves exhaust scavenging on the high-revving LT6, freeing up power across the entire RPM range and especially up top.
• Ported throttle bodies — The Z06 uses dual throttle bodies feeding the flat-plane V8. Porting removes restrictions and allows the engine to breathe more freely at full throttle.
• Aftermarket intake — More airflow into the engine from the start of the intake tract. Works in concert with the ported throttle bodies for a compounding airflow improvement.
• E85 fuel conversion — E85 ethanol has a much higher octane equivalent than pump gas, allowing significantly more aggressive ignition timing and fueling — the biggest power driver in this package.

Why E85 Makes Such a Big Difference

E85 is one of the most effective power adders available to naturally aspirated and forced induction engines alike. For a high-compression engine like the Z06's LT6, E85 allows the calibration to advance timing well beyond what 93 octane permits without risk of detonation. It also runs cooler combustion temperatures, which is a bonus for engine longevity.

The catch? The entire fuel delivery side of the tune needs to be reworked. Injector duty cycles increase significantly because E85 requires roughly 30–35% more fuel volume than gasoline to achieve the same air-to-fuel ratio. Getting the fuel trims, injector scaling, and closed-loop targets dialed in correctly is critical — and it's where a professional calibration separates itself from a generic tune file.

The Z06 pulled 590 whp and 408 lb-ft of torque at the wheels — a tremendous result for a naturally aspirated build on E85 from an already exceptional platform.

Why Remote Tuning Works for Builds Like This

N2Speed's remote tuning process puts professional-grade calibration within reach regardless of your location. The customer handles dyno time at a local shop — we handle all of the calibration work remotely, iterating on the tune file in real time based on data logs and dyno feedback. It's efficient, thorough, and produces results that match or exceed what you'd get from an in-person session.

This C8 Z06 is a perfect example. The combination of long tube headers, ported throttle bodies, intake, and E85 required a completely custom calibration — not a base map, not a flash. Every table was touched and verified against real-world data.

Ready to Unlock Your Corvette's Full Potential?

N2Speed offers remote custom calibrations for C8 Corvettes and a wide range of GM and Ford platforms. Get in touch and let's talk about your build.