The LSA came equipped with rectangle port (LS3-style) cylinder heads. However, the supercharged heads were Rotocast for added strength. The engines also use the same 4.065 in. bore block. In fact, the engine block casting number is the same as the LS3.
I was told I could have a custom computer chip burned so I could run TPI fuel injection on the 350. The EFI system will be modified with an Edelbrock High-Flow base manifold and runners, ported stock plenum, 52mm throttle body, bigger injectors, and an adjustable fuel pressure regulator. I will be using 1-5/8-inch headers and a 3-inch dual exhaust.
Both engines have the same injectors and dual fuel pumps. However, they max out around 65 psi. The fuel pumps are controlled by a module that increases fuel pressure in relation to boost. There are aftermarket pumps and voltage controllers that will work with the factory ECM to increase capacity.
Like other LS engines, a cam swap is common. The LSA has a very small camshaft. Upgrading to a LS9 camshaft is worth about 30 hp, however, it won’t make more power until 4,800 rpm. It’s really only worth it if you plan on running at high rpm. Larger, aftermarket cams can add about 50 hp. Going as high as 0.630 in. of valve lift is also common. The table below gives some information on what to expect from different cams. (Note: We are assuming a standard blower, pulleys, and tune on pump gas.)