General Motors LS-based small-block engine: Difference between revisions

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* 2007–2014 [[GMC Yukon XL]] 1500

*=====LH8=====*

The LH8 was introduced in 2008 as the V8 option for the Hummer H3. It was the simplest, most basic 5.3L V8 of its family, lacking any special technologies. Also known as the Vortec 5300, the LH8 was available in the H3 and GM mid-size pickups through 2009.

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=====LS427=====

The '''LS427''' is a {{cvt|7011|cc|L cuin|1}} engine based on the LS7. Theand LS427introduced replacesin theJune dry-sump2020. oilingIt systemwas withdesigned aonly wet-sumpas systema andcrate includesengine ato higher-liftprovide camshaft.increased Thispower engineand wassimplified onlyinstallation availablefor asaftermarket aand craterestomod optionapplications. andIt did not appear in any production vehicles. It was introduced in June 2020 and discontinued in January 2022 along with the LS7.

Unlike the LS7, the LS427 uses a conventional wet-sump oiling system with an F-body aluminum oil pan and wet-sump pump, eliminating the need for an external oil tank and plumbing required by the LS7's dry-sump system. This change makes the engine easier to install in a wider range of vehicles.

Peak output is {{cvt|570|bhp|PS kW|0}} and {{cvt|540|lbft|Nm|0}} of [[Torque#Machine torque|torque]] with a 7000&nbsp;rpm redline.<ref>{{Cite web|url=https://www.chevrolet.com/performance-parts/crate-engines/ls/ls427-570|website=chevrolet.com|title=GM LS427/570|access-date=July 17, 2023}}</ref>

PeakThe outputLS427 is equipped with a unique hydraulic roller camshaft featuring .591&nbsp;in intake and .590&nbsp;in exhaust lift and longer duration (227° intake / 242° exhaust), resulting in a power increase to {{cvt|570|bhp|PS kW|0}} and {{cvt|540|lbft|Nm|0}} of [[Torque#Machine torque|torque]] with a 7000&nbsp;rpm redline.<ref>{{Cite web|url=https://www.chevrolet.com/performance-parts/crate-engines/ls/ls427-570|website=chevrolet.com|title=GM LS427/570|access-date=July 17, 2023}}</ref>

Other changes include fifth-generation Camaro Z/28 exhaust manifolds and a 14&nbsp;in manual transmission flywheel from the Z/28 platform, replacing the LS7’s stock components. It retains key LS7 features such as forged steel crankshaft, titanium connecting rods, CNC-ported aluminum cylinder heads with 70cc combustion chambers, and a 7000&nbsp;rpm redline.

The engine is supplied fully assembled with intake manifold, fuel rails, injectors, throttle body, ignition coil packs, balancer, and water pump. It requires a specific LS427/570 engine controller (P/N 19420000) calibrated for this engine.

The LS427 was discontinued in January 2022 along with the LS7.

===4.06 in. bore blocks (2007–2017)===