Poly 318 Engine Parts List
(Applicable to 277, 301, 303, 313, 318, 326, 390, 402 engines)
I have compiled a thorough parts list for the poly 318 and other A-block engines using brands I use and trust or for availability for items that have limited manufacturers. For interchange information, see the parts interchangeable page. For other brands, these part numbers should cross-reference. Many of these parts can be found at Summit Racing, JEGS, Speedway Motors, Rock Auto, Napa Auto Parts, and other retailers.
Bearings:
- Cam: LA273/318/340/360, King or Clevite
- Mains: LA273/318/340, King or Clevite
- Rods: LA273/318/340/360, King or Clevite
Distributor: All LAs and Magnum 318/360 (see my ignition technical article for more details on selecting and timing the ignition system)
- Recommended: Richard Ehrenberg’s USA-made “HiRev 7500” distributor, control unit, coil, and ballast resistor.
- Note: Cheap units, such as Pertronix and Proform, are built with inferior Chinese components and often have reliability and performance issues for optimum performance and reliability including erratic and bouncing timing.
- Note: 2000 – 2013 Mopar Performance distributors with the miniaturized Accel GM HEI internals are prone to erratic timing.
Distributor Gear: LA273/318/340/360
- Comp Cams 420
- Howards Cams 94415
- Crower 76010
Distributor Intermediate Shaft Bushing: Melling M-63030B
Flexplate and Flywheel: 1962 onward A/LA273/318/forged-crank 340 confirmed neutral balanced
- LA360 and cast-crank 340 flexplates and flywheels can either be neutral balanced or weighted to balance the rotating assembly, so neutral confirmation is required.
Freeze Plugs:
- 1956 – 1961: Melling MEP14B (brass dish)
- 1956 – 1961: Sealed Power 3811014 (steel dish)
- 1962 – 1966: Melling MPE-613BR or Sealed Power 3818010 (brass cup with cam plug)
- 1962 – 1966: Napa 567014 (brass cup without cam plug)
- Note: these kits do not include the oil bypass plug (see my oil bypass article for details on this important factor)
Gaskets:
- Full Set: FelPro FS7734PT2
- Full Set: Best Gasket RS579G
- Cylinder Head: FelPro 7734PT
- Exhaust Collector: FelPro 9045
- Confirm OEM diameter
- Exhaust Manifold: FelPro MS9342B
- Fuel Pump: FelPro 6579
- Intake Manifold (superior fiber type): Best Gasket 18019
- Intake Manifold (steel, can leak depending on surface trueness): FelPro MS9344SH
- Note: See my intake manifold installation article for discussion on the issue with the factory metal gaskets and for instillation process/tips.
- Oil Pan: FelPro OS6566C2 or 1806
- Thermostat Housing: FelPro 35063
- Timing Cover Set: FelPro TCS65631 or TCS45284
- Valve Covers: FelPro VS11828R or VS11828C
- All other gaskets: LA273/318/340
Heater Bypass Hose: DAYCO 70476 for 3/4″ barbs
Lifters:
- Solid: Melling JB2084 or Sealed Power AT2084
- Hydraulic: Melling JB879
- Note: LA lifters are the same diameter but are taller than A-block lifters and require shorter custom pushrods.
Oil Filter (canister):
- Gasket: FelPro 70522
- Warning: Don’t use the rubber gasket since they are prone to pushing out and leaking.
- Filter: Wix 51076
Oil Filter (spin-on):
- Adapter Plate to Block: FelPro 70522
- Warning: Don’t use the rubber gasket since they are prone to pushing out and leaking.
- Very Short Filter 3.79”: Wix 51085
- Short Filter 4.338”: Wix 51068
- Standard Filter 5.18” 1 qt.: Wix 51515
- Long Filter 7” 2 qt: Wix 51773
Oil Pump:
- 1956 – 1961: Melling MEL51
- 1962 – 1966: Melling MEL72 or MEL72HV (high-volume)
- See my oil pump blueprinting technical article for details on a superior oil pump setup for the A-block.
Pistons:
- Cast: Egge L2050
- Note: Search ebay for the pistons since they are usually cheaper there than through Egge
- Forged: Race Tec Pistons (California) for custom forged
- Billet: Gibtec Pistons (Colorado) for custom billet
Piston Rings: Use LA318 for stock rebuilds. Refer to piston manufacturer for custom pistons.
- Mahle 40069CP (Moly)
- Mahle 50069CP (cast)
- Mahle 41226 (chrome)
Pulley (Crank):
- 1956 – 1992 A/LA
- Note: 1970 – 1992 LA273/318/340 dampers and pulleys have a slightly different pulley bolt pattern, so using a 1970 – 1992 pulley on a pre-1970 damper or pre-1970 pulley on a later damper requires elongating pulley holes, which will not have a negative impact on anything.
Pulley (Water Pump):
- 1956 – 1969 A/LA when using iron lefthand intake short-snout pump.
- 1970 – 1992 LA when using aluminum righthand intake long-snout pump.
Pushrods: These are OEM lengths, but worn equipment on non-adjustable rocker arms or modified engines may require custom lengths and should be measured on all rebuilds.
- Solid Lifter: MPR55 or Sealed Power RP3030 (5/16” x 8.418”)
- Hydraulic Lifter: MPR153 (5/16” x 8.364”)
Rocker Arm Adjuster Screws (positive lock): 3/8″-24
Rocker Arm Shaft Expansion Plugs: Dorman 555-082 (45/64″)
- Note: The poly rocker arm shaft expansion plugs are larger than the LA shaft plugs, and the A-block plugs are not marketed through major distributors. I have researched and personally tried five different plugs, and the Dorman 555-082 is the best fit.
Spark Plug: 3/8” short-reach such as Autolite 85, Champion 63 (formerly J12Y), etc.
- Warning: Do not install LA-type 3/4″ long-reach plugs, such as Autolite 65. They will contact the piston.
- Note: There is a lot of misinformation about spark plugs with some people claiming A-block engines will only run well with one brand over the other, which is inaccurate. Any reputable brand spark plug will perform just fine with a healthy A/LA ignition system.
Starter Motor: see my article on available starter motors
Thermostat: (see my cooling system article for selection and discussion)
- 180°: Stant 45358
- 180° High-flow: Mr. Gasket 4363
- 195°: Stant 45359
- 195° High-flow: Mr. Gasket 4365
- Note: High-flow thermostats should be paired with a high-flow water pump and larger radiator for optimal utilization.
Timing Set: LA273/318/340/360
- Cloyes C3002K (OEM-type single non-roller)
- Cloyes C3028X (double roller w/ cam advance adjustment)
- Cloyes 93503X9 (billet double roller w/ cam advance adjustment)
Valve Cover Retainers:
- Poly valve cover bolt cup washers: Skateboard truck washers are almost identical to the early A-block washers
- Beck/Arnley 039-6659 (2003 – 2006 Honda Element EX 2.4L, info courtesy Michael Lindsay)
- Note: These steel retainers are larger than the early 277/318 retainers but may be of interest to some.
Valve Springs: 1.70″ installed height springs for OEM machining.
- Many LA springs are 1.7″ installed height.
- Always follow the cam requirement for seat and open pressures at the cam’s maximum lift.
Valve Spring Keepers: 7° or 10° matched to valve stem diameter, groove type, and retainer angle.
Valve Spring Retainers: 7° or 10° degree matched to stem diameter, springs, and keepers.
Valve Stem Seals:
- 3/8″ Stem Positive Seal: FelPro SS72730
- 3/8″ Stem Umbrella: FelPro SS70014
Water Pump:
- Use 1957 – 1969 A/LA iron pump for factory left-side intake and short pump to match A-block pulleys (Figures 1 and 2).
- OEM Type: WP58180, TFW43030
- High-flow: FlowKooler 1701
- Note: Should use a high-flow thermostat for optimal utilization.
- Use 1970 onward aluminum pump for right-side intake but will need 1970 onward pulleys since the pump is longer than the pre-1970 (Figures 1 and 2).
- OEM Type: WP58181, TFW43026
- High-flow model: Tuff Stuff 1465NA
- Note: Should use a high-flow thermostat for optimal utilization.
Figures

