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JE Pistons 274646 Forged Dome Piston Set Bore Alloy - 3.858 2618 6-Cylinder

(1984-1989 Porsche 911 Base/Carrera/Speedster)

Part of: JE Pistons Forged Dome Piston Set Bore

Other options in this family: JE Pistons 353906 JE Pistons 186235 JE Pistons 359152 JE Pistons 361278 JE Pistons 258239

Manufacturer

Picture for manufacturer JE Pistons

Part Number

274646
11 reviews
Sale Price

$1,499.99

Estimated ship date Wednesday, November 11

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Product Details

JE Pistons 274646 is a high-performance forged piston set engineered specifically for air-cooled Porsche 911 engines with Nickel Ceramic bore coating. Precision-machined from 2618 aluminum alloy, these pistons deliver superior strength and thermal stability for demanding applications while maintaining compatibility with stock stroke and rod length configurations.

Key Features:

  • Application-specific forgings with optimized, uniform crown thickness for strength and heat dissipation
  • 3.858-inch bore diameter with 1.290-inch compression distance and 0.905-inch pin diameter
  • Dome-style crown design for increased compression ratio
  • Valve pockets machined to accommodate high-lift camshafts
  • Contact reduction groove minimizes frictional drag and parasitic power loss
  • Accumulator groove enhances top ring stability and sealing performance
  • CNC-machined side relief with lower support band for additional skirt strength
  • Precision CNC-machined ring grooves accept OEM-style rings (except 2.7L applications)
  • Honed pin bores with double pressure-fed pin oilers for optimal lubrication

Each set includes six matched pistons, wire locks, and JE ProSeal piston rings. Designed and manufactured in the USA to exacting tolerances for professional engine builders and serious enthusiasts.

Products specifications

Fits

1984-1989 Porsche 911 Base/Carrera/Speedster

Bore

98mm

C/D

32.8mm

Comp Ratio

11.5:1

Dome CC

44.2

Gram Weight

477

Head CC

90

Oversize

3mm

Rod

127mm

Skirt Type

R

Stroke

74.4mm

Add-On

905-2500-15-TSC

Engine

PORSCHE AIRCOOLED 6 CYL

Bore Diameter

98.00

Compression Height

1.290

Add-On

905-073-MW

Piston Pin Wall Thickness

0.150

Oil Ring Thickness

0.119

Piston Avg Wt

481

Second Compression Ring Thickness

0.06

Forging Type

Round

Out of Stock Message

Call for Availability

Top Compression Ring Thickness

0.0595

Piston Pin Length

2.500

Cylinder Head

3.2 Liter

Product Market

Sport Compact

Piston Head Type

Dome

Add-On

J612U1-3858

Ringset Included

Yes

Industry

Automotive

Piston Material

2618

Piston Pin Outside Diameter

0.905

Piston Volume

44.2

Make

PORSCHE

Category Hierarchy

Pistons>Piston Kits

Prop 65

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

Piston Quantity

6

Shipped fast and accuratly within a week.

Best price and easy to use web site.

purchased two shocks for my truck, best price online , they were here within a week. I will definitely order from them again....thanks....

Easy payment method

Best price I've seen online and the shipping is extremely fast. I would definitely use this site again for future automobile needs.

Excellent communication, quick, easy, and lowest price.

quick delivery of the parts I need to fix my jeep

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Ordered a CTEK charger. Great price, and recieved it in 3 days. Very pleased.

Glad I found Autoplicity.com. Big potential...<br><br>Ordered parts on Friday, missed 1st delivery attempt to office yesterday (Weds), but received today (Thurs). Little slow on the shipping, but not in a rush for these parts. We typically receive UPS pkgs in 1-2 bus days from Chicago suburbs to Metro Detroit. This took a bit longer, but again - it was not a problem & well worth the savings.<br> <br>Wish web-site would actually separate items for just my car vs all vehicle matches. Finding what I wanted was very difficult, but I'm very pleased with pricing & follow through. I've been back on Autoplicity 2 times now looking for add'tl parts for another vehicle, but have yet to locate them amongst the 100's - even 1000's of results that do not match. If finding them were easier & these add'tl items offer similar savings, I would have spent hundreds more by now. <br><br>If this is a new company, hopefully they can correct the advanced search option as well. Entering a part by vendor name should net results when the brand is listed on the home page & can be found in general queries. Even when I entered the part # for an item it shows no results, but again - searching several dozen pages, I am able to find the same part #. The savings were worth the headache it took to find the brake pads for my BMW, so I won't give up just yet. <br><br>Thanks Autoplicity! Here's to a potentially great future!!

Quick shipping. Good info on sttud will definitely irder again

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