Corvette Mods: Inside the Engine Bay of the ProCharger C8 Corvette! (SEMA 2022)

The 725+ HP, plug-and-play Stage II ProCharger C8 Corvette system will (hopefully) soon be 50-state legal while running a 10.5 quarter mile!

Torch Red Corvettes are my gravity. And so that’s how I found myself in the ProCharger booth at SEMA 2022 last week staring at intake piping and an air-to-water intercooler. Now, we’ve already told you a little about the ProCharger C8 Corvette kit, which adds roughly 140 (Stage I) to 230+ horsepower (Stage II) over a stock Stingray. But, since this was my first time seeing one in person, ProCharger’s Erik Radzins was kind enough to answer a few questions and walk me through the fundamentals.

Fingers crossed, I’m hoping to coordinate with ProCharger to drive and review one of the company’s C8s on the streets (like I did with the original Stingray right HERE). But in the meantime, here are the highlights of our conversation…

Cost & Installation

While ProCharger currently lists four C8 kits on its website, the Stage II system costs roughly $18,000. As I write this, most other boosted C8 systems require sending your vehicle to a shop (and spending about $25K to $30K all-in). For ProCharger, they’re currently shipping kits to customers for DIY or local shop installs.

Radzins talked at length about the simplicity of the ProCharger install. No permanent modifications (save for some carpet trimming). Plug and play components. You’ll only need access to the rear inner fender liners as well as the trunk’s rear access panel. A moderately talented DIYer should be able to complete the installation in under 15 hours.

It’s supposedly less of a hassle than a bumper-off exhaust install.

Based on what I saw, it definitely looks like a fun weekend project, save for the time spent shipping one’s ECU to ProCharger for calibration. This ensures OEM functionality of everything else in the vehicle, but eats a little time.

Also worth noting: ProCharger supplies re-sized trunk access panels with the kits and, while they’re some lost volume, golf clubs still fit. (#CorvetteApproved)

Specs & Performance

The Stage II system’s 725+ crank horsepower translates to right around 650 real-wheel ponies. Radzins notes that there are horsepower variations between their three test C8s, but ProCharged-vs-baseline gains remain even across multiple vehicles. In the real world, this allows ProCharger drivers to run consistent 10.5-second quarter mile passes at 132mph. (Interestingly, they don’t see much of a difference between running a dedicated drag pack versus good drag-ready tires on the OEM C8 wheels.)

By the way, on stock Michelin Pilot Sport 4S tires, the C8 is still pretty capable, running 10.6s and 10.7s all day long with a good launch. And, of course, those tires are terrific (and safer) for street driving and some light (road course) track work.

Here’s everything included with a full system purchase (partial tuner kits are also available) —

HO SYSTEM

STAGE II SYSTEM

Engineering & Performance

Corvette fans have been waiting for two long years for companies like ProCharger, East Coast Supercharging, and Lingenfelter to release boosted C8 systems. But cracking current-generation GM computers proved insanely difficult.

The challenge at hand, outside of computer cracking, is torque management.

To shift properly and safely in a variety of driving scenarios, the C8’s transmission control module needs to request specific amounts of torque at precise moments. (Usually, a drop in power that’s measured in milliseconds.) But, in builds where the TCM and ECU can’t coordinate, the transmissions ultimately UNDERestimate the LT2’s power output. Which causes clutch wear and other driveline components to fail.

With access to the ECU and TCM computers, ProCharger is able to map everything so a full C8 Stage II system can be installed without upgraded axels or clutches (assuming one doesn’t get too sticky with the tires).

Speaking of the LT2, Radzins approximated the LT2’s tune to be about 70 to 80% similar to the C7 generation Corvette’s LT1 engine. However, ProCharger is very impressed with the LT2 overall. Thanks to a revised cam and other improvements, the LT2 builds power longer and higher in the rev range than the LT1.

Octane Requirements & California Emissions

A quick primer for those who don’t live in California or one of the growing number of states that follow Cali’s emissions laws. For a modified vehicle component to become road legal in California, it must first prove to the California Air Resource Board (CARB) that it doesn’t dramatically increase pollution versus a completely stock vehicle. Once approved, CARB issues an Executive Order (E.O.) allowing specific vehicles modified with specific components to pass emissions tests.

This is, effectively, how any aftermarket part becomes 50-state legal from an emissions perspective.

As I write this, C8 ProCharger installations are for race use only. But as soon as the company completes an HTC (hardtop convertible) C8 kit — which is slightly different than the coupe — they’re sending the cars through the CARB certification process to become 50-state emissions legal.

California emissions are also why C8 ProCharger complete systems are tuned for 91 Octane fuel. I asked Radzins if, on the base ProCharger tune, folks in states with 93 Octane would see improved performance. I’m badly summarizing and simplifying his answer (as a person who is not a tuner),  but the gist was this —

• Yes, there’s a little more power to be found, but not much.
• Part of this is because, because of the CARB certification process, they can’t have a tune that adjusts itself too much.
• Also, LT-era engines aren’t as good as, say, Ford’s dual overhead cam Coyote V8s, at adjusting for octane, so tuners like ProCharger have to be a little more conservative with how they map things.

For those who want to push their tuning things like higher octane fuels, E85, and methanol, ProCharger recommends buying one of the Tuner kits which don’t include calibrations. Tuner kits also, naturally, lack emissions compliance.

ProCharger C8 Corvette Videos

Photos: Derin Richardson, Michael S. Palmer, ProCharger