Product images and videos are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Exterior Components› Body Panels and Components
United Engine & Machine Co
CHEVROLET 377/400 ROD 5.7/5.565 FLAT TOP +7CC 2V KB HYPER PISTON SET
SKU: U00B KB172.STD
Advanced — 4+ hours
Overview
These pistons are recommended for Chevy small block Gen I engines, specifically 6.6L/400 CID engines from 1970-1980. They can also be used on 377 CID engines with specific crankshaft, rod length, stroke, and deck height configurations.
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Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
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Specifications
| Brand | United Engine & Machine Co |
| Part Number | U00B KB172.STD |
Videos
HOW TO BUILD A SMALL BLOCK CHEVY EPISODE 3: INSTALLING PISTONS AND RODS
BUDGET 350 Chevy DIY How to install Pistons and Rings in your SBC
Fool proof installing pistons on rods of a Small Block Chevy
Engine Failure!? Watch if you are running Hypereutectic pistons!
Engine Building Part 4: Pistons, Rings, and Rods
SBC Rods and Pistons Orientation and Piston Orientation in Block
KB Pistons and Ring End Gap
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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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Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.
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