When Redline Motorsports was approached to build the ultimate sleeper out of a 2014 Chevrolet Camaro ZL1 (with only 40 miles on the odometer), most would think they’d just turn up the boost and maybe add a little nitrous. It’s a proven formula, and one that Redline has done many times over. But there is always that one guy that wants to be different. So Redline decided to step this one up and bolt in an IPS Motorsports twin-turbo system. The kit uses low-mounted 62.5mm Garrett 35R billet turbos, TiAL wastegates, and a front-mount air-to-air intercooler. When I spoke with calibrator extraordinaire Howard Tanner at Redline, he expected the kit to be making around 14psi with the stock 6.2L LSA engine on pump gas. And in case you are wondering, the factory supercharger assembly will be replaced by an LS3 intake manifold.
While some may see it as a sacrilege to ditch the factory TVS1900 supercharger, it is a necessary evil in making some serious power, making cool sounds and really pushing the envelope. After all, the ZL1 is a great starting point for a turbo build when you think about it. And though the engine combo is completely off the map, the owner was quite intent on keeping the stock converter and 6L90E transmission so as not to give up any street manners. Save for the turbo kit and intake manifold, this is going to be a stock car with a whole lot more gusto. Maybe this is how GM should have built it in the first place.
After master tech Jay Healy completed the install of the IPS twin-turbo system, Howard Tanner got to work on Redline's Land & Sea chassis dyno by dialing in a custom engine calibration. Since the twin snails would be moving considerably more air, Redline would need to compensate by adding larger injectors – Injector Dynamics 850cc units to be specific. In addition, the significantly different inlet required new MAF tables, and some other alterations needed to be made for relocated sensors such as the second IAT sensor (normally inside the blower). Howard also remarked that the spark tables are considerably different with the turbo setup because additional spark advance is needed in the lower RPM to help spool the turbos, though the overall timing was significantly lower because of the enhanced airflow. The relatively flat power curves (after full boost) indicate that the exhaust housings on the turbos were well sized, and there is still some room to grow. Though at 646-rwhp and 653 lb-ft of torque the turbocharged ZL1 is already a huge leap ahead of its stock counterparts, it is good to know that its potential far exceeds that of the factory blower. Some ZL1 faithful may criticize this choice, but they'll be too far in the rearview to hear.