318 Pistons Dodge Plymouth Chrysler Mopar 318 5.2L Magnum 390 Stroker Piston Sets

The 318 Mopar V8, also known as the 5.2L, and 5.2 Magnum has been around since 1967 as part of the LA engine series and the 1992 and newer Magnum series. We offer a wide range of pistons for the Mopar 318 engines. The 318 is a dependable, reasonably small and light, efficient engine package, that can be built to do everything from power a street work truck to being an all out drag, oval track or road racing engine. Many people tend to overlook the 318 as a high performance engine, which is a shame as it offers many benefits, and the core engines are easy to come by and relatively inexpensive.

 

Choosing the best 318 Pistons for your High Performance 5.2 Magnum or 318 Engine

In building up a 318, one of the main things that must be changed is the pistons. From the factory, the 318 was just about always equipped with low compression pistons, as it was intended more for long life, using low octane regular gasoline, than for high power output. Installing higher compression, higher quality pistons is one of the biggest improvements you can make to your 318 engine. A stroker crankshaft is another item that really brings the 318 to life as it greatly increases torque and power. The 4 inch stroker crank builds a .030 oversize 318 into a 390 and the increase in performance is dramatic.

318 Piston Quick Jump Link Index

• Custom 318 Pistons
• 318 Poly Pistons
• Diamond Forged 318 Pistons
• Icon Forged 318 Pistons
• KB Hypereutectic 318 Pistons
• Sealed Power 318 Stock Replacement Pistons
• Silvolite 318 Stock Replacement Pistons
• Wiseco Forged 318 Pistons
• 318 Connecting Rods

We offer a wide range of replacement pistons for the Dodge, Chrysler, Plymouth 318 engines. We have everything from stock replacement pistons, to custom 318 forged racing pistons, stroker pistons and quite a bit in between. The 318 and 5.2L Magnum piston listings on this page include  high performance and racing forged pistons at the top of the page, and stock type replacements at the bottom of the page.

If you are looking for a complete 318 stroker kit they are on our site here: 318 Stroker Kits

 

Wiseco Pistons 318 A engine & 5.2 Magnum Mopar Forged Pistons

Pro Tru Street Series Wiseco 318 Mopar Forged Flat Top Piston and Ring Kits Wiseco 5.2 Magnum 318 Piston Kits Include and Feature: 8 4032 Alloy aluminum forged Flat Top pistons Chromium alloy steel piston pins spiro lock pin retention rings plasma moly piston ring set piston rings are 5/64 5/64 3/16 oversize symmetrical radiused valve pockets allow use of high lift cams and big valves pressure fed pin oiling precision finished pin hole ArmorGlide skirt coating for friction reduction and quieter operation. These pistons are for use with a 318 3.313 in. stock stroke crank and stock length 6.123 in rod. The piston pin size is stock .984 in. They work in the LA series 318 engines and also the 5.2 Magnum series engines. These forged pistons can be used with a press fit pin rod, but we strongly recommend using them with a floating pin 4340 H beam type rod set. Scroll to the bottom of this page for connecting rods.
Bore Size	Cubic Inches	Comp. Ht.	Volume of 2 valve pockets	Comp. Ratio with chamber size of:		Part #
				62cc	64cc
3.910 in. standard size	318 cid	1.800	-5cc FT	9.6-1	9.4-1	Wiseco PTS529AS $618.91 $587.96  + DISCOUNTED SHIPPING! Shipping in the USA for this item is only $29.95 when you spend $499.00 or more!
3.940 in..030 oversize	323 cid	1.800	-5cc Flat Top	9.7-1	9.5-1	Wiseco PTS529A3 $618.91 $587.96  + DISCOUNTED SHIPPING! Shipping in the USA for this item is only $29.95 when you spend $499.00 or more!
Wiseco Pro Tru 318 - 5.2 Magnum Stroker Piston and Ring Sets The below 4 piston sets have been discontinued by Wiseco and are no longer available. The specs are being left on display here to help those who may need the info. The piston and ring sets listed below are for use with a 4 inch stroker crank, 6.123 long rod and .984 diameter wrist pin.
3.940 in..030 over	390 cid	1.460	-21cc Dish Top	9.6	9.4	pt125h3
3.950 in..040 over	392 cid	1.460	-21cc Dish Top	9.6	9.4	pt125h4
3.940 in..030 over	390 cid	1.460	-5cc Flat Top	11.3	11.1	pt136h3
3.950 in..040 over	392 cid	1.460	-5cc Flat Top	11.4	11.2	pt136h4

 

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ICON Forged 318 Pistons and 318 Stroker Pistons

Keith Black ICON forged 318 Piston sets are available in flat top, dish top and dome top designs, for stock 318 stroke engines and 318 390 stroker engines. All of the sets listed below feature:

• Wrist pins and pin fitting included
• Accumulator groove included
• Double pin oilers are force fed from the oil ring
• Large valve relief depths and diameters allow for high lift cams and oversized valves
• Piston sets are balanced to +/- 1 gram
• Pin lock grooves included to ease lock removal
• Fully CNC Machined
• Double spiral locks included

 

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KB Hypereutectic 318 Piston Sets KB hypereutectic high performance Mopar 318 pistons offer a significant improvement in performance for your engine, at a very affordable price. We have these in standard stock bore size as well as all popular oversizes. If you want a great performance piston, but do not need all of the performance benefits and higher cost of top of the line forged pistons, KB performance pistons are an excellent alternative for many applications. We do not recommend hyper pistons for use with superchargers, turbochargers or nitrous systems. Made from Hypereutectic 390 Alloy with 16% silicon 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 Hypereutectic 318 Pistons for Stock Stroke Chrysler Dodge Plymouth 318 and 5.2 Magnum Engines Stock 318 specs for reference Bore size is 3.910 Stock 318 stroke is 3.310 rod length is 6.123 pin size is .984 Ring grooves are 5/64 5/64 3/16 Crankshaft These pistons are for use with a stock stroke 318 / 5.2 crank Connecting Rods These pistons are for use with stock length rods 6.123 inches long with a .984 wrist pin size 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 ccs displacement of dome, or dish, and valve reliefs, measured in ccs CR Compression ratio estimates based on a .030 oversize, zero deck and .039 compressed head gasket Bore Size Finished bore size, in inches, that piston is designed for Piston set includes 8 pistons, 8 wrist pins and spiral locks Piston and ring kit includes 1 Complete piston set and 1 Moly piston ring set
318 Flat Top Pistons
CH	Wt	ccs	CR with head chamber of:				Bore Size	Piston and Ring Kit
			57cc	60cc	64cc	68cc
1.810	507	-5	10.4	10.1	9.6	9.2	3.910 standard	KB167 KTM $649.09 $590.09
							3.930 + 020 over	KB167 KTM20 $649.09 $590.09
							3.940 + 030 over	KB167 KTM30 $649.09 $590.09
							3.950 + 040 over	KB167 KTM40 $649.09 $590.09
							3.970 + 060 over	KB167 KTM60 $649.09 $590.09
318 Dome Top Pistons
1.810	541	6	12.2	11.7	11.0	10.4	3.910 standard	KB399 KTM $712.01 $647.29
							3.930 + 020 over	KB399 KTM20 $712.01 $647.29
							3.940 + 030 over	KB399 KTM30 $712.01 $647.29
							3.950 + 040 over	KB399 KTM40 $712.01 $647.29
							3.970 + 060 over	KB399 KTM60 $712.01 $647.29

 

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Small Block Mopar Forged Pistons 5.2 318 390 Mopar Diamond Stroker Pistons

Diamond pistons are available for a wide range of small block Mopar engines, bore sizes, and strokes. Diamond Racing Mopar pistons are all high strength forged pistons. They offer high strength, but at the same time modern technology allows these pistons to be light weight improving engine performance further. These pistons are far superior to any cast or hypereutectic type piston. Small block Mopar Diamond piston sets offer reduced friction, better ring sealing, faster acceleration, more horsepower and torque in your high performance street, strip or race car engine. We are pleased to offer the entire line of Diamond Pistons to our customers at great discount pricing.

Mopar Dodge Chrysler 318, 5.2 Magnum, 390 Diamond Pistons

The Diamond forged pistons listed below, for the 318 engine, are for use with 4" stroker crankshafts. At .030 oversize, the 318 with the 4" stroker crank builds a 390 cubic inch engine. If you are using a stock stroke crankshaft in your engine project, you will need to select pistons to work with the stock stroke. If you are building a stroker engine using a 4" stroke crankshaft, then you will want to choose the matching 4" stroker pistons. We also have the 4" stroker cranks available as well as connecting rods, rotating assemblies and stroker kits.

Small Block Mopar 5.2L Magnum and 318 Stroker Pistons Dish Top

These Dodge 318 pistons are for use with a 4" stroker crank, they are not for use with a stock stroke 318 crank. Click here for our 318 Stroker crank page

 

Small Block Mopar 318 5.2L Magnum Stroker Pistons Flat Top

 

These 318 stroker pistons are for use with a 4" stroker crank, they are not for use with a stock stroke 318 crank. Click here for our 318 Stroker crank page

 

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KB Silvolite Replacement 318 Stock Piston Sets 5.2 Magnum and older LA Series 318 Standard Cylinder Bore size is 3.910 inches Year The model years listed are the original model year engines that this piston is designed to be a direct replacement for. In most cases, the pistons can be used in other model years engines if you want to get a different compression ratio or piston ring combination. If you have any questions about piston applications please contact us for assistance. CR Compression Ratio when used with original head chamber volume, gasket, deck height, etc. Notes Further information about the piston. Comp Ht is the compression height of the piston, as measured from the center of the wrist pin bore to the top flat part of the piston. Ring Grooves Widths of the piston ring grooves. Interchange Shows OEM part number pistons this set will replace, as well as the equivalent Federal Mogul piston number. (the 7 digit numbers are the original Chrysler part numbers and the FM part numbers are the equivalent Federal Mogul - Sealed Power part numbers) Head Shape Image showing the piston top layout Bore Size Recommended finished cylinder bore diameter in inches Piston Set Contents Part number shown is for a set of 8 pistons and includes wrist pins and pin locks where required.
Year and CR	Notes	Ring Grooves	Interchange	Head Shape	Bore Size	Piston Set Part Number
1963 - 1978 8-1	Dodge Truck premium engine. Flat top COMP HT: 1.658 PIN DIA: .9842 Offset	2-5/64 1-3/16	2525000 2808519 3004551 3004555 2808650 FM LC371P		3.910 standard	1278
					3.930 20 over	1278-020
					3.940 30 over	1278-030
					3.950 40 over	1278-040
					3.970 60 over	1278-060
1967 - 1984 9-1	Flat top with4 valve reliefs. 1991 and later use early style rings . COMP HT: 1.741 PIN DIA: .9842 Offset Vin Code X, Y	2-5/64 1-3/16	2808405 3004509 3420222 3685751 4342772 4638072 FM 285NP		3.910 standard	1266
					3.930 20 over	1266-020
					3.940 30 over	1266-030
					3.950 40 over	1266-040
					3.970 60 over	1266-060
1967 - 1984 9-1	Flat top with4 valve reliefs. 1973 and later press fit. 1991 and later use early style rings. *Same as 1266 with COATED SKIRTS COMP HT: 1.741 PIN DIA: .9842 Offset OEM Vin Code X, Y	2-5/64 1-3/16	2808405 3004509 3420222 3685751 4342772 4638072 FM 285NCP		3.910 standard	1266C
					3.930 20 over	1266C-020
					3.940 30 over	1266C-030
					3.950 40 over	1266C-040
					3.970 60 over	1266C-060
1985 - 2002 9-1	Hypereutectic Flat Top. Not intended for Racing applications COMP HT: 1.741 PIN DIA: .9842 Offset OEM Vin Code Y, T	2-2.0mm 1-4.0mm Shallow Groove	4778855(L) 4778857(R) FM H814P		3.910 standard	3234H
					3.930 20 over	3234H-020
					3.940 30 over	3234H-030
					3.950 40 over	3234H-040
					3.970 60 over	3234H-060
1985 - 2002 9-1	Hypereutectic Flat top COATED SKIRTS COMP HT: 1.741 PIN DIA: .9842 Offset OEM Vin Code Y, T	2-2.0mm 1-4.0mm Shallow Groove	FM H814CP		3.910 standard	3234HC
					3.930 20 over	3234HC-020
					3.940 30 over	3234HC-030
					3.950 40 over	3234HC-040
					3.970 60 over	3234HC-060
1985 - 2002 9-1	Flat Top Same as set number 3234 with an early model size ring pack COMP HT: 1.741 PIN DIA: .9842 Offset	2-5/64 1-3/16	FM 526P		3.910 standard	3247
					3.930 20 over	3247-020
					3.940 30 over	3247-030
					3.950 40 over	3247-040
					3.970 60 over	3247-060

Chrysler Dodge Plymouth 318 and 5.2 Magnum 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 5.2 318 Connecting Rods Molnar Technologies H Beam 318 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 $803.53 $694.01  + DISCOUNTED SHIPPING! Shipping in the USA for this item is only $29.95 when you spend $495.00 or more!

 

Eagle SIR 5.2 Magnum and 318 I beam connecting rods 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 5.2L Magnum and all 318 length SIR6123CB

 

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Sealed Power Mopar 318 and 5.2 Magnum Stock Replacement Pistons

We offer better than original, stock replacement Chrysler 318 pistons from Sealed Power. These pistons are great for stock rebuilds, muscle car restorations, and even light duty performance applications. These pistons are a cast piston, which is the type originally used in these engines from the factory. The Sealed Power Piston sets we have are based on the original designs, but with improvements due to modern manufacturing techniques ensuring a better piston, at a great price. The piston sets are weight matched before packaging by Sealed Power. The pistons come with a selectively fit piston pin. We also offer the matching sealed power piston rings for all of these piston sets.

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318 Poly Pistons

We are pleased to offer hard to find forged pistons for the 318 Poly head engines. We offer these for standard crankshaft stroke applications as well as 318 poly stroker pistons.

Our 318 Poly pistons are manufactured on a built to order basis. The average build time is 4 weeks from the day we submit the order to the plant. These are forged piston sets and can be made to any bore size, stroke, rod length, etc. Since they are built to order, you can get a set of pistons exactly like you want for your project. The pistons are built for us by Ross Racing Pistons.

The below prices include: 8 custom forged 318 poly pistons, 8 wrist pins, pin fitting, lock removal indents and spiro locks. We can also provide piston rings for most bore sizes. Piston rings are priced separately. When you place an order on our website for 318 Poly pistons one of our representatives will contact you to get the details of your project to insure you get pistons built to exactly the specifications you need.

Description	Price
318 Poly Flat Top
318 Poly Dome Top
318 Poly Reverse Dome or Dish Top

 

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Mopar 318 Custom Pistons

If you do not see 318 shelf stocking pistons on this page with the specs you need, we also offer forged custom 318 pistons to cover any application. We have custom pistons available for the the 318 A, 318 LA series and 318 5.2L Magnum series.

Custom 318 forged piston sets are available in any bore size, compression ratio, ring configuration, pin size etc. They are available as flat top, dome top and dish top designs. They are also available for normally aspirated engines, turbocharged, supercharged and nitrous boosted engines.

Please contact us for assistance, pricing, and build times for custom 318 piston sets.

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TRW Speed Pro 318 Forged Pistons

TRW forged piston sets and Speed Pro forged pistons are available for the 318 Mopar A engine. The Speed Pro / TRW piston set listed below is a complete set of 8 pistons including the piston pins and pin retaining lock rings. The piston sets are all weight matched before packaging. These 318 forged pistons set the standard for years with their line of forged replacement pistons for stock type engines. Speed Pro forged pistons further that tradition with their line of Powerforged pistons.

If you are looking for other Mopar engine stock replacement pistons, you may view them by clicking here: Sealed Power Mopar cast pistons We also have Speed Pro hypereutectic and forged pistons for many Mopar V8 engines listed here: Speed Pro pistons for Mopar V8 engines

Speed Pro TRW Forged Piston Set for Mopar 318 and 5.2 L Magnum Engines

 

318 Performance Engine Building

 

Back to top 318 Pistons page

 

 

Links to related sections of our website:

318 Stroker Kits | CP Pistons Index Page | Diamond Pistons | Ross Pistons | Wiseco Pistons |