Engines and Components› Engines, Blocks and Components

ATK ENGINES

GM POSI SUV 4.88 AXLE

$2,230.56

SKU: A040 RAXP0105G

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Special Order
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

This engine is ATK’s remanufactured version of the Mercruiser 377CI MPFI engine with a 4.030″ bore (383ci). It has the upgraded 4340 Forged Crankshaft and Forged Pistons along with the Mercruiser camshaft installed. It is to be used with the Mercruiser MPFI system, aftermarket EFI or a carburetor conversion. This engine will make 405HP @ the crankshaft and 380HP @ the prop which is how Mercruiser rated their power ratings. This engine is a reman version of the Mercruiser 377 Scorpion. It can be used in other applications with the proper supporting modifications.

Fitment

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Specifications

BrandATK ENGINES
Part NumberA040 RAXP0105G

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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