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JE Pistons 379439 FSR Ultra Series Piston Kit Compression - 85.00mm 13.5 1

(1999-2007 Suzuki GSX1300R Hayabusa Base)

Part of: JE Pistons FSR Ultra Series Piston Kit Bore Compression

Other options in this family: JE Pistons 379448 JE Pistons 379447 JE Pistons 379434 JE Pistons 379436 JE Pistons 379442

Manufacturer

Picture for manufacturer JE Pistons

Part Number

379439
8 reviews
Sale Price

$1,274.99

Estimated ship date Sunday, November 15

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Product Details

The JE Pistons 379439 FSR Ultra Series Piston Kit delivers race-proven performance for high-compression engine builds. Machined to a 4.00mm oversize bore of 85.00mm with a 13.5:1 compression ratio, this kit is engineered for applications demanding maximum power density and thermal efficiency.

JE's FSR (File-to-Fit, Street/Race) Ultra Series pistons are manufactured from high-strength forged aluminum alloy using JE's proprietary forging process. The FSR platform combines the durability of a race piston with streetability, featuring optimized skirt profiles, reduced compression heights, and lightweight design to minimize reciprocating mass and improve throttle response.

Key Features:

  • Bore Size: 85.00mm (4.00mm oversize)
  • Compression Ratio: 13.5:1 — ideal for naturally aspirated high-performance builds
  • FSR Ultra Series construction — forged from high-silicon aluminum alloy for strength and heat resistance
  • Low-tension ring package for reduced friction and improved ring seal
  • Optimized dome/dish geometry for efficient combustion chamber fill
  • Lightweight forging reduces reciprocating mass for improved engine response
  • CNC-machined to tight tolerances for consistent fit and performance
  • Full floating wrist pin design for reduced piston rock and wear
  • Designed for file-to-fit installation, allowing precise bore-to-piston clearance adjustment

JE Pistons is one of the most trusted names in performance piston manufacturing, supplying pistons to professional racing teams across drag racing, road racing, and off-road competition. The FSR Ultra Series brings that same engineering pedigree to high-performance street and track builds. MPN: 379439.

Products specifications

Fits

1999-2007 Suzuki GSX1300R Hayabusa Base

Piston Head Type

Dome

Piston Material

2618

Prop 65

WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

Forging Type

FSR

Lateral Gas Ports

Yes

Piston Volume

-3.5

Engine Type

ICE

Product Type

Engine Piston Kit

Industry

Powersports

Bore Diameter

3.346

Wrist Pin Length

2.250

Piston Series

JE Pistons

2nd Groove Width

0.048

3D Undercrown Milling

No

Accumulator Groove

Yes

Anodize Top Ring Groove

No

Combo 2

No

Contact Reduction

No

Double Pin Oilers

No

DVGP

No

Econo Undercrown Milling

No

EN Plating

No

Gas Distribution

No

Intake Diameter

1.400

Mill Undercrown

No

Oil Groove Width

0.11100

Pin Fit

Yes

Skirt Coat

Yes

Smooth Crown Finish

No

Top Groove Width

0.04000

Tuff Skirt

No

Ultra Dome

No

Ultra Groove

No

Ultra Groove Plus Gas Port

No

Vertical Gas Ports

No

Cylinder Head

SUZUKI M/C 01

Wrist Pin Outer Diameter

.787

Engine Stroke

2.480

Product Market

Powersports

Compression Ratio Actual

13.5

Piston Average Weight

268

Exhaust Angle

14

Exhaust Depth

.125

Exhaust Diameter

1.200

Intake Angle

14

Intake Depth

.180

Piston To Wall Clearance

-0.002499

Thermal Crown

Yes

Shipping was slow, but item arrived 2 days earlier than expected. A good shopping experience was expected and was received.

great

Simple and fast

No issues

Nice

Very good pricing!

Very reasonable

quick delivery

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