My Account
My Garage
Shopping Cart

Shopping Cart

0 items in your Cart
View Cart
Subtotal
Track
My Order
MY GARAGE Select Vehicle
MY GARAGE

JE Pistons 242886 Forged Flat Top Piston Set Bore - 4.125 8-Pack

(1970-1980 Chevrolet 400 Small Block)

Manufacturer

Picture for manufacturer JE Pistons

Part Number

242886
13 reviews
Sale Price

$1,023.99

1 left at this price

delivery box

Usually delivered within 2 days

free shipping

FREE SHIPPING

Check out with

ApplePay
Authorize Seller Badge
No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The JE Pistons 242886 forged piston set delivers professional-grade performance for high-performance engine builds. Machined from 2618 aluminum alloy, these flat top pistons feature a 4.125-inch bore diameter, 1.000-inch compression distance, and 0.927-inch pin diameter. This matched set includes 8 pistons with oil rail support, honed pin bores, double pressure-fed pin oilers, and wire locks.

Key Features:

  • 2618 forged aluminum construction for exceptional strength and durability
  • 23-degree flat top design for optimized compression
  • Application-specific forgings ensure uniform crown thickness
  • Contact reduction groove minimizes frictional drag
  • Accumulator groove increases top ring stability and sealing
  • CNC-machined side relief with lower support band for additional skirt strength
  • Oil rail support included for enhanced ring stability
  • Honed pin bores with double pressure-fed pin oilers and wire locks included

JE Pistons has manufactured industry-leading forged racing pistons for over 60 years, trusted by professional engine builders for Chevy, Ford, Mopar, and Buick applications. Each piston set is precision-matched for balanced performance. Recommended ring set: J10008-4125-5.

Products specifications

Fits

1970-1980 Chevrolet 400 Small Block

Block Height

9

Bore

4.125

Bore (in)

4.125 in.

Bore (mm)

104.775mm

CID

428

Comp Height

1

Comp Ratio @ 58CC

13.1:1

Comp Ratio @ 64cc

12.2:1

Comp Ratio @ 76CC

10.7:1

Compression Distance (in)

1.000 in.

Dome Volume

-5

Gram Weight

391

Notes

Oil rail support included. 0.295 inch deep intake pocket.

Oversize

STD

Pin Diameter (in)

0.927 in.

Piston Head Volume (cc)

+5.00cc

Piston Material

Forged aluminum

Piston Ring Thickness

1/16 in. x 1/16 in. x 3/16 in.

Piston Style

Flat top, with four valve reliefs

Quantity

Sold individually.

Rod

6

Stroke

4

Wrist Pin Style

Press-fit or floating

Product Market

Domestic

Piston Pin Outside Diameter

0.927

Piston Pin Length

2.750

Out of Stock Message

Call for Availability

Piston Volume

-4.3

Add-On

927-2750-15-51S

Add-On

927-042-CS

Cylinder Head

CHEVROLET 23 DEG 20/30

Compression Height

1.000

Top Compression Ring Thickness

0.064

Industry

Automotive

Piston Pin Material

5115

Bore Diameter

4.125

Forging Type

Round

Piston Material

2618

Piston Head Type

Flat

Engine

SMALL BLOCK CHEVROLET

Category Hierarchy

Pistons>Piston Kits

Make

Chevrolet

Second Compression Ring Thickness

0.064

Piston Pin Wall Thickness

0.150

Ringset Included

No

Piston Avg Wt

391

Oil Ring Thickness

0.218

Add-On

J10008-4125-5

Wrist Pin Outer Diameter

0.927

Piston Quantity

8

Prop 65

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

Good product

Easy ordering

Easy and good price

So far it’s good

Nice

Good service

Great service, cheap prices and fast shipping. I will repeat.

simple, easy. Thanks

more detail in the product review

Would like to know how fast will shipping be and will list part fit my 2009 Acura TSX map light console

Great price, exactly what I needed. I will definitely return to Autoplicity for future autoparts orders! Thanks!

Good nice price

Very quick service and lowest price.

Share icon
Return Policy
Returns are easy at THMotorsports

Not happy with a purchase? No problem. We've made returning items as easy as possible. And most purchases can be returned for free for 30 days. Learn more about our Returns Policy