Manoli Katakis 
Extreme Turbo Systems recently revealed more details of its twin-turbo C8 Corvette packages, including pricing and power numbers. The system was announced last week, just ahead of the 2021 Texas Mile drag race event at Houston Raceway park, in Baytown, Texas.
While it remains non-compliant with the encrypted ECU of the C8 Corvette, the twin turbo kit nevertheless carries a starting price of $13,995 USD for the base PT64 unit, said to be good for 1,200 horsepower. Next up is the PT68, which is said to be good for 1,500 horsepower and will come in at $18,490 with the $4,000 heat exchanger. Then there’s the top-end PT76 option is said to be capable at making up to 2,000 horsepower, and stickers at $18,895 USD with the $4,000 heat exchanger. Radical power numbers, to be sure. But it’s unclear if the C8 Corvette twin-turbo kit is street legal at this time.
“Tuning?! Don’t worry, we have you covered! In the next couple of weeks we plan to release our PNP Motec Piggyback to the public,” reads a social media post from ETS. The Washington-based performance shop has been working on this kit for about a year, with an impressive time at the drag strip in October 2020, running the quarter-mile in just 9.95 seconds at 144mph.
To refresh, a “piggyback” is a controller that intercepts signals to and from the factory ECU, and is able to modify them to achieve a desired tuning result. The base process of a piggyback module is the same as a chip or a flash tune, but the data needs to go through many more steps to reach the same goal. It’s a solution with limited capability, and has so far been something turnkey performance shops have avoided, despite existing demand to extract more power out of the LT2 V8 engine found in the C8 Corvette Stingray.
An off-the-shelf example of a piggyback controller is a Burger JB4 system, which isn’t street legal, and is meant only for track and motorsport use. Ultimately, what this means is that the encrypted C8 Corvette ECU remains locked – as we originally reported would be a major hurdle nearly two years ago. The Tremec 8-speed dual-clutch transmission also features an encrypted control unit.
ETS will offer a choice of two intercooler options for its C8 Corvette twin-turbo kit. The first is described as Hot Piped, which is meant for low boost applications. This comes with a pair of blowoff valves, clamps and mounting hardware. The second is a water-to-air intercooler with a side heat exchanger, meant for mid- to high-boost applications. This too comes with a pair of blow off valves, clamps and mounting hardware, but also adds a side heat exchanger with a fan shroud, feed and return water lines, couplers, and two water pumps.
The turbocharger “hot parts” included in the C8 Corvette twin-turbo kit are two header-to-turbocharger pipes, two 3.5-inch exhaust pipes with 4-inch tips, two external wastegate dump tubes, two 44 millimeter wastegates, two exhaust gaskets, along with the necessary clamps and mounting hardware. The turbo intake kit will include a pair of K&N filters, a PCV breather kit, and clamps. The Turbo oil feed and return kit is comprised of two oil feed fittings, two oil feed lines, two oil drain tubes, an oil feed valve, an oil return scavenge pump, an oil return pump wiring harness, an oil return breather filter, and the necessary gaskets, clamps and mounting hardware.
Extreme Turbo Systems summarizes each component for the C8 Corvette twin-turbo kit as follows:
Turbocharger Selection – Your choice of 1200whp, 1500whp or 2000whp capable turbochargers!
The PT64 option is recommend for 90% of our builds where the customer is looking to build the ultimate street car with quick spool and transient response. This kit is capable of right around 700whp on the stock clutches and stock engine and over 1200whp with upgraded clutches, built engine and a fuel system.
The next step up from the PT64 is the PT68, which is recommend for anyone looking to make over 1500whp. The PT68 option requires a built engine, upgraded clutches, upgraded fuel system, etc.
The next step up from the PT68 is our PT76 option, which is capable of over 2000whp! This kit requires a built engine, built transmission, upgraded clutches, fuel system, etc.
Intercooled vs non-intercoolered – We have (2) options available depending on your horsepower goals.
The first option is our non-intercoolered option. This option is great for customers not wanting to stress their engine and make a bit more power than stock. We recommend this option for around 600whp and right around 5-6 psi of boost. The water to air intercooler option can always be added later on if you decide you want to make over 600whp or run more than 5-6 psi.
The second option is our water to air intercooler with side heat exchanger. This option is designed to support over 2000whp! This intercooler features (2) water pumps, an ice box, and (2) HUGE 1000whp+ W2A cores. The side heat exchanger is located in the driver side fender opening and includes a shroud that’s compatible with the high output factory fan. The integrated ice box is ideal for any 1/4 mile or 1/2 mile racer providing intake air temps below ambient temperature in most cases.
Oil Scavenge Pump – This is the first pump in this field to offer external motor brushes for easy/inexpensive replacement. The custom heatsink allows the entire motor/pump head assembly infinite rotation allowing optimal orientation of the in/out ports, including port functional reversal. This pump was designed from the ground up to handle the most extreme conditions found in any motor vehicle, with a special emphasis on turbocharger oil scavenging applications. Built on extremely rugged spur gear technology, this small-frame 350F continuously rated pump offers aerospace/military-grade quality in a compact/lightweight package.
Wastegates in line with the flow with the very high flow rates of the new billet wheel turbo’s, we have found the wastegate system must be very efficient, or else boost creep could be induced. As well as keeping run away boost under control, a very efficient wastegate system will allow tuners to start a tune at a much lower boost pressure, ensuring that the whole tuning process is done safely.
Critical Lines Away from heat – All of the Oil/Water lines are routed away from heat, down and around the turbos, instead of over and across the turbos. This will ensure a lifetime service life for these lines, while also lowering the temperatures of the fluids within the lines.
Fully ported at every transition – From the 3-bolt flange to the exhaust flanges and even the PCV barbs in between, we pride ourselves on the best craftsmanship and attention to detail in the industry. This means that all flanges are surfaced, all transitions ported, and all pieces are clean. These details may not make any major power differences, but it can be the difference in numbers such as 998 vs 1002whp.
Warranty – (3) Year warranty on all fabricated parts. Manufacturer warranty on turbochargers, wastegates, etc.
