Our fellow modders and hot rodders on the West Coast have always had an uphill battle when it comes to increasing the performance of their rides in the Golden State. California’s strict emission standards for passenger vehicles choke the owner’s ability to add horsepower and torque in modern cars and trucks. For owners of the C8 Corvette in California, they were mostly limited to simple intake and exhaust changes. That is until ProCharger pushed to have their C8 supercharger kits for the Corvette to get a CARB EO number.
What is a CARB EO number?
CARB stands for the California Air Resources Board and is an agency within the California state government whose main goal is to limit and reduce air pollution in the state. This agency can trace its roots back to the late forties and formed in 1967 as the California Air Resources Board when the Federal Air Quality Act of 1967 was enacted, giving California the ability to set its own more stringent air quality rules due to California’s unique geography, weather, and expanding number of people and vehicles.
“Thanks to us being first to market, we began the C8 CARB EO approval process quite a while ago. Compared to other EOs on other platforms, our efforts to attain the EO were significantly more difficult. This is because the emissions standards keep getting tighter, the C8 platform is one of the newer, stricter standards for which we had to comply, and the C8 engine bay is very tight for location of all of the related hardware. — Cliff Hall, ProCharger
CARB has always been one, or several, steps ahead of federally mandated emissions standards for automobiles, making modifying your car or truck in the state difficult. The agency will grant an EO (executive order) number to certain aftermarket parts that can be proven to not increase emissions on the vehicles they are designed for. This is a lengthy and stringent process that can take years to get approved. Without a CARB EO number, aftermarket parts that increase engine performance are not allowed to be fitted to your vehicle and the result of trying to skirt the agency’s rules can result in heavy fines and a lot of headaches.
Because of this strict and time-consuming process of testing and certification, it is no surprise when you look at a list of CARB-approved aftermarket parts, they tend to offer entry-level horsepower gains and consist of simple upgrades like intake systems, cat-back exhaust systems, and mild “Stage 1” canned-tunes. Rarely are there any aftermarket parts that offer big increases in horsepower that also get a pass from CARB. To get a CARB EO number for something that offers a massive leap in power, like a C8 supercharger kit, can prove to be very challenging to seemingly impossible.
What CARB-Friendly Power Can You Expect?
A supercharger increases horsepower and torque in an engine by supplying the intake charge with more air than it can draw in naturally. More air means more fuel which equals more power. But burning more fuel also equates to more emissions out of the tailpipe, so getting a CARB EO number for a supercharger kit usually means only a very mild increase in performance. But this is not the case for ProCharger’s C8 supercharger kits.
The team at ProCharger worked tirelessly to not only get a CARB EO number for their Stage 1 HO kit, but also their higher-horsepower Stage 2 C8 supercharger kit for LT2-powered Corvettes. They did this without compromising the performance they delivered with either kit before they pushed them to get a CARB EO number. The Stage I HO kit offers gains of 170 horsepower with 5 psi of boost and the Stage II kit gives you 7.5 psi for an increase of 230 horsepower. These kits offer these gains while still utilizing the stock exhaust system and 93-octane pump gas.

Pictured here is the low-profile system that works with both the coupe and HTC body styles. The intricately designed belt drive system and air-to-water cooling system allow you to bolt on 230 horsepower or more in your driveway with cutting, welding, or special tools.
What’s even more impressive is the performance potential when installed on the LT2-powered E-Ray. The E-Ray comes with a 160-horsepower hybrid system powering the front wheels, turning an LT2-powered Stingray into an eAWD hybrid supercar making a combined 655 horsepower. The E-Ray also received a CARB certification, which means you can transform it into a Corvette that makes almost 900 horsepower with Procharger’s C8 supercharger kits!
In addition to our fleet of C8s purchased for R&D and track testing (drag strip and road course), we purchased a C8 dedicated to emissions testing. This allowed us to conduct extensive emissions testing—comparing stock and supercharged emissions data—to ensure our supercharger system met the increasingly stringent standards of the C8 platform. — Erik Radzins, Procharger
Not only can owners of LT2-powered Corvettes in all 50 states enjoy adding hundreds of horsepower to their all-American mid-engine sports car, but they can also enjoy a C8 supercharger kit that is American-designed and manufactured that fits without any cutting or welding. The Stage I and Stage II kits offer a true bolt-on installation that can be done at home over the weekend with hand tools and includes PCM reprogramming. If ordered with the low profile intake manifold, there is still enough room for the retractable hard top on the convertible models to fit in the rear compartment when folded up.
Now our fellow C8 Corvette owners on the West Coast can enjoy more power that won’t get them in trouble with the local law thanks to ProCharger’s C8 supercharger kits. Whether you’re enjoying a cruise up the Pacific Coast Highway, a trek through the Sierra Nevada Mountains towards Lake Tahoe, or a drive through the massive sequoia trees on the Avenue of Giants in the northern part of the state, you can enjoy it even more with a big jump in performance over the factory delivered sub-500-horsepower output Chevrolet gave you.