When doing an engine swap with a GM LS engine and installing an aftermarket oil pressure gauge it can be tough to find the right fitting for the top rear port on the engine. Luckily for us, Earl’s GM oil pressure gauge adapter fittings make it an easy task. The GM LS engine uses a 16 millimeter by 1.5 millimeter port on the top rear of the engine, this odd size coupled with the location makes it tough to install an electric oil pressure sensor or hose without adding a bunch of adapters. Earl’s oil pressure gauge adapters makes it easy to fit a pressure sensor, dash 3, or dash 4 hose to the port on the block. Its black anodized twenty twenty-four T8 aluminum construction is more durable than sixty sixty-one-T6. These fit all GM LS series engine blocks. These metric adapters are a straight thread design which means they should be sealed with a crush washer unlike NPT threads which are tapered and are normally sealed with pipe sealant or plumbers tape. Make that LS engine swap a breeze with Earls GM Oil pressure gauge adapter.