Engines and Components› Engines, Blocks and Components

ATK ENGINES

GM RWD 4L60E 4SPD

$1,908.63

SKU: A040 1275AA-HP

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Advanced — 4+ hours

Description

The ATK ENGINES 1275AA-HP is an HP42 Chevy 540 Base Engine, producing over 660 horsepower and 650 ft-lbs of torque. This crate engine features a Dart Big M block, Manley forged crankshaft and rods, forged pistons, a hydraulic roller camshaft, and ATK HP aluminum cylinder heads. It is designed for high-performance applications and requires specific supporting components for installation.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandATK ENGINES
Part NumberA040 1275AA-HP

Videos

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ATK Performance crate engine review
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Buy with Confidence

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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