2. Because the engine upgrades don’t change the external appearance of the LSA engine, you’ll notice no difference between the before and after shot. With some much stock-appearing equipment on the car – especially when it wears the original wheels and tires on the street – this ZL1 could be considered a sleeper.
3. The modifications began by removing the Camaro’s front fascia. This would facilitate the camshaft swap with the engine still in the car, as well as a heat exchanger upgrade. That provided the necessary access to the stock heat exchanger and allowed for easier removal of the radiator.
4. With fascia, heat exchanger and radiator removed, the coolant was drained and the disassembly of the top of the engine commenced. It’s a pretty straightforward process and it’s easier to remove the intercooler “hat” from the blower assembly, instead of trying to remove the blower/intercooler as a single component.
5. The exhaust also had to be removed, but that involved more than simply unbolting the manifolds from the engine. The ZL1 has an aerodynamics-optimizing belly pan under the engine compartment – it even wraps around the transmission – and it must be removed prior to the exhaust system.
6. Here’s one of the stock stainless exhaust manifolds and converters. The stock exhaust flows reasonably well, given the necessary emissions and sound targets Chevrolet had to work with. Nevertheless, high-flow long-tube headers will add some mid- and upper-range power.
7. With the exhaust removed, the stock heads were popped off and the front of the engine torn down far enough to facilitate removal of the camshaft. If done carefully, the cam can be changed without the removal of the oil pump – although the stock timing chain must be retained. This car only had a couple hundred miles on it before the swap, so it was fine.
8. In goes the new camshaft. It’s Livernois’ Stage 2C High Lift cam, with .646-inch lift on both the intake and exhaust sides, 224/236 degrees of duration and a lobe separation angle of 117 degrees. That compares with the stock cam’s .480/.480 lift, 198/216-deg. duration and a lobe separation angle of 115 degrees.
9. The aftermarket camshaft necessitated the swap to a three-bolt cam gear from an earlier style LS engine. The stock camshaft/cam gear uses a single, large bolt. The three-bolt style matches the design of early LS engines.
10. With the front cover on the engine, a new balancer from Innovators West is installed, along with a Metco oversized crank pulley ring. The new balancer is required to bolt on the pulley ring, which won’t attach to the stock balancer. The ring expands the crank pulley diameter to 9.55 inches, enabling the blower to make about 4 pounds of additional boost when used with a smaller-diameter supercharger pulley.
11. Livernois’ own ported cylinder heads are featured on the engine. They’re CNC-ported versions of the stock L92-style lungs, which are good for up to 30 additional horsepower – and probably more with the higher-boost airflow from the LSA’s supercharger.
12. The new heads’ intake ports are cut to boost airflow by about 30 cfm. The benefit is felt more at the top end on a naturally aspirated engine, but with the forced induction of the LSA, the extra air contributes to greater horsepower and torque even at low RPM. Nice.
13. The heads retain the stock 2.16-inch intake and 1.59-inch exhaust valves and the combustion chambers are left alone to ensure the stock 9.1:1 compression ratio is retained for pump-gas compatibility, which the car consumed during its 9-second run.