On our last installment the folks at Lingenfelter Performance Engineering had first got their hands on a 2014 Chevrolet Silverado, powered by the new EcoTec 5.3L V-8 (L83), for baseline testing. This Gen V direct-injection engine bares many similarities to the popular LS series of engines, but with advanced cylinder head design and increased efficiency through years of technological advancement. As discussed, its Flex Fuel capabilities definitely gave the LPE crew some headroom when it comes to fueling for a power adder. The 30% increase in fuel needed for E85 meant that the same increase would be possible with straight gasoline to accommodate boost.
Using a Magnuson TVS1900 supercharger designed for the previous generation 6.2L truck engine, LPE fabricated adapter plates to bolt to the Gen V heads. With the supercharger bolted to the plates, the pulleys were the last issue to rectify on the retrofit. By designing and machining a front support bracket in-house, twin idler pulleys were added to route the belt and the supercharger pulley was spaced slightly for proper alignment. Using 93-octane pump gas, the blower was set to 6psi and the computer was given a custom calibration using a few different tuning software. Chief Engineer Graham Behan stated that they initially removed 5-degrees of spark advance, but added some back in as needed. He also remarked that the tuning is quite a bit different than the LS engines, "more torque model controlled," though it is very similar to the other GM DI controllers such as the E39, but with more features.
Output jumped from 298hp and 332 lb-ft of torque to 397hp and 425 lb-ft – that’s pretty stout for a little 5.3L engine with a small blower on low boost. That comes out to around 525hp at the flywheel. And even more impressive is the flat power “curve.” It’s no wonder the heavy Silverado (5,360lbs to be exact) now runs a 13.89 at 100mph. The best part is: they aren’t done. Mike Copeland, LPE’s VP of Operations, said “Based on our testing, we believe there is more capacity available in the factory fuel system.” Clearly this new high compression motor loves boost, and LPE is in development for new camshafts and CNC programs for the cylinder heads. This is getting to be a real exciting time to be a GM enthusiast. Stay tuned for more updates.