Engines and Components› Pistons and Piston Rings

Diamond Motorsports

LSX FT Piston Set 4.125 Bore -4.8cc 12-Degree

$1,516.66

SKU: 21565-RS-8

Out of Stock
Out of Stock
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Advanced — 4+ hours

Overview

The Diamond Motorsports LS2K 12° Piston Set is a high-performance engine component designed for GM LS-Series engines. This forged piston set features a flat top design with a 4.125-inch bore and a -4.8cc piston volume. It is engineered for use with a 3.622-inch stroke and a 6.125-inch rod length, with a standard pin size of .927 inches. The pistons are constructed with forced pin oilers, moly-coated skirts, 3D pockets, and an inboard forging design for enhanced durability and performance. This set includes pins, locks, and support rails as required.
Show original supplier description
Piston - LSX 12 - Forged - Flat Top - 4.125 in Bore - 1.304 in Compression Height - 1.5 x 1.5 x 3.0 mm Ring Grooves - Minus 4.80 cc - GM LS-Series - Kit

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.

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

BrandDiamond Motorsports
Part Number21565-RS-8
CategoryEngines and Components > Pistons and Piston Rings > Pistons

Videos

Pistons for Boost | Diamond Pistons | Custom Pistons

Pistons for Boost | Diamond Pistons | Custom Pistons
Pistons 101: Piston Upgrade guide! wrist pins, coatings, rings and more!

Pistons 101: Piston Upgrade guide! wrist pins, coatings, rings and more!

The Truth: Cast vs Hypereutectic Pistons - Which One Is Better? | Engine Building 101 |

The Truth: Cast vs Hypereutectic Pistons - Which One Is Better? | Engine Building 101 |
The TRUTH About Pistons Choosing The RIGHT Piston For Your Engine! Is Expensive Better??

The TRUTH About Pistons Choosing The RIGHT Piston For Your Engine! Is Expensive Better??
DISASTER WAITING TO HAPPEN?? The DANGERS of Hypereutectic Pistons! Think BEFORE You BUY!

DISASTER WAITING TO HAPPEN?? The DANGERS of Hypereutectic Pistons! Think BEFORE You BUY!

5,000+ Trusted brands
1M+ Enthusiasts
5M+ Parts sold
(760) 282-4645 hello@motormia.co

Buy with Confidence

Returns & Fitment

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

Shipping

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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

View Full Shipping Policy