Exterior Components› Body Panels and Components

United Engine & Machine Co

CAST PISTON 4.1L GM

$59.16

SKU: U00B 1820.020

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

Moderate — 2–4 hours

Description

The United Engine & Machine Co 1820.020 is a piston designed for engine rebuilding. It is made from Cast 332 Alloy and features a dish-type piston head with a +7.5cc crown volume. The piston has a bore diameter of 3.4646 inches (88 mm) and a compression height of 1.63 inches (41.4 mm), with a compression ratio of 8.5.

The manufacturing process is done in-house and includes alloying, casting, heat treating, and diamond machining. The diamond finishing process creates a consistent skirt finish. This piston has an offset pin configuration and a press-type pin.

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

BrandUnited Engine & Machine Co
Part NumberU00B 1820.020

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.

View Full Return Policy