Campbell Enterprises Header
Shop By Vehicle
Shop By Brand
Search For Parts
LiveZilla Live Chat Software

340 Pistons KB Chrysler Dodge Plymouth Mopar

Keith Black 340 Pistons

Hypereutectic 340 Pistons

High performance KB Mopar 340 pistons offer a significant performance improvement for your engine, at a very affordable price. We have these piston sets available in a wide range of sizes including standard bore and many popular oversizes. If you are rebuilding a Chrysler, Plymouth, Mopar, Dodge 340 engine and are looking for improved performance, without the higher cost of forged pistons, KB performance pistons are an excellent alternative for many street, muscle car restoration, cruising and mild street / strip applications.

Mopar 340 Engine Specs

For reference the original stock specifications were:

  • Engine block deck height 9.600 inches
  • Cylinder bore standard size 4.040 inches
  • Crankshaft stock stroke 3.310
  • Connecting rod length 6.123 inches
  • Wrist pin diameter .984

We do not recommend hypereutectic pistons for use with superchargers, turbochargers, nitrous systems or for serious racing engines. For those applications we strongly recommend forged pistons. Our complete piston index list for stock replacement, cast, hypereutectic and forged pistons is available here: CE Engine Pistons Index

Keith Black Mopar 340 Piston Features:

  • Hypereutectic 390 Alloy
  • Fully machined head and valve reliefs
  • Accumulator groove to aid with compression ring seal
  • Diamond finished skirts
  • CNC machined pin bores to insure straight and accurately sized bores

KB 340 Pistons for use in Chrysler Dodge Plymouth Mopar 340 Engines

KB243 340 Piston

  • Stroke These pistons are for use with a 3.310 inch stock stroke 340 crank, OEM or aftermarket
  • Connecting Rod Length 6.123 inch
  • Wrist Pin Size .984 inch diameter
  • Ring grooves are 5/64 5/64 3/16
  • CH Compression Height This is the measurement from the centerline of the piston pin bore to the top flat part of the piston
  • Wt Piston weight in grams followed by wrist pin weight in grams
  • ccs displacement of dome, or dish, and valve reliefs, measured in ccs
  • CR Compression ratio estimates based on a .030 oversize, -.041 deck clearance and .020 compressed head gasket
  • Bore Size Finished cylinder bore size, in inches, that piston is designed for
  • NOTES Centered pin. Piston above deck .018.

What is Included?

  • Piston set includes 8 pistons, 8 wrist pins and locks
  • Piston and ring kit includes 1 Complete engine piston set and 1 piston ring set

Mopar 340 Flat Top Pistons

CH Wt ccs CR with head chamber of: Bore Size Piston Set Piston and Ring Kit
57cc 60cc 64cc 68cc
1.840 597 / 132 -6 10.9 10.5 10.0 9.6 4.040 standard KB243 KB243 KTM
$629.55 $572.32

Add To Cart
4.060 + .020 over KB243 20 KB243 KTM20
$629.55 $572.32

Add To Cart
4.070 + .030 over KB243 30 KB243 KTM30
$629.55 $572.32

Add To Cart
4.080 + .040 over KB243 40 KB243 KTM40
$629.55 $572.32

Add To Cart
4.100 + .060 over KB243 60 KB243 KTM60
$629.55 $572.32

Add To Cart

Mopar 340 Connecting Rods

While you are replacing your engine pistons it is a good time to also upgrade your rotating assembly by installing modern connecting rods. Why risk damage to your rebuilt performance engine by using old stock connecting rods that have been through who knows what kind of abuse.

With the high cost of machine shop service these days you can often upgrade to far stronger modern rods for not much more than the cost of reconditioning a set of stock rods.

Molnar Technologies H Beam 340 Connecting Rods

Molnar Technologies 340 Connecting Rods Logo

molnar 340 h beam connecting rod

Molnar Technologies H Beam 340 rods are machined from billet 4340 steel, and then heat treated to provide improved strength. To make the rods even stronger, they are shot peened to which also increases fatigue life. All Molnar connecting rods are fitted with highly durable premium bronze bushings for use with floating pin type pistons. Each rod set includes ARP fasteners, moly lubricant and installation guidelines.

All Molnar rods are finished in the United States at the Molnar Technologies shop in Michigan. Critical rod dimensions are are held to very precise tolerances of +/- .0001 of an inch, which is the tightest tolerance you will find in the performance and racing aftermarket.

  • Description and Length Engine model that rod is made to for and length of the rod, as measured center to center, in inches.
  • Weight Weight in grams, of one complete connecting rod assembly
  • Bolt Size Bolt dimensions in inches, Rods come with ARP2000 fasteners installed
  • Rod Pin Size Crank rod journal diameter
  • Pin Size Piston pin diameter, in inches
  • BE Width Width of the crankshaft end of one rod
  • PE Width Width of the piston end of one rod
  • Part Number Molnar Technologies rod set part number. Set includes 8 connecting rods
Description and Length Weight Bolt Size Rod Pin Size Pin Size BE Width PE Width Part Number
6.123 Chrysler with .984" Pin 623 7/16 2.125 0.984 0.927 1.03 DH6123TSB8-A

Add To Cart


Eagle SIR 340 I beam connecting rods

Eagle 340 I beam connecting rod

Eagle Specialty Products SIR connecting rods are an economically priced alternative to the time and expense involved in reworking a set of stock OEM rods. SIR connecting rods are forged from 5140 steel and most are available for both pressed fit pin use, or bushed to work with full floating piston pins. ESP I beam SIR Eagle connecting rods utilize ARP 3/8" Wave Lok bolts and nuts. Eagle SIR rods are economically priced and are often less expensive than having your old stock rods reconditioned.

Length Pin Notes Part Number
6.123" .984 bronze bushed Full floating, stock 273, 318, 340, 360 length SIR6123CB



Campbell Enterprises Performance Parts | About | Contact Info | Privacy Policy | Terms
copyright © Motorsports Parts Corporation T/A Campbell Enterprises. All rights reserved