the poly (thru 1966) and wedge (67-up) 318 bare blocks are the same size, you'd be hard pressed to tell them apart just looking at them. But, the poly heads are shaped differently so they stick out the sides further, that's how it got the name "wide block". Different exhaust....along with almost everything else.
Full Answer
What's the difference between a 318 and a 318 wide block?
The wedge heads (first used by Chrysler on the B engines) were far smaller, and lighter, than the old Hemi and polyspherical heads (318s with the poly heads are still often called "wide blocks" though the block itself is about the same size as that of the LA 318).
Can a 318 engine block be retrofitted?
Since 273, 318 diameter, crankshafts are interchangeable between these engines. blocks, retrofitting isn’t an option. connecting rods and pistons used in the original configuration. from the one to which the crank was originally mated. Therefore, rebuilt. meet the flank. Obviously, it will be necessary to chamfer the
Are 318 cid and 273 CID blocks the same?
Although all blocks are virtually identical left-side motor mount than their 273 and 318 cid counterparts. to a four-bolt main configuration, they should be avoided. The areas to comfortably handle the added bolts. block strength. The only way to get both is with a Mopar Performance “X” race block (p/n P4120637).
Are 340 and 318 crankshafts interchangeable?
Since 273, 318 and 340 small blocks all have the same stroke and main journal diameter, crankshafts are interchangeable between these engines. Production 360 engines, however, were never blessed with a forged
Is there a big block 318?
Most commonly known as the "wide-block 318," "big-block 318," or "Poly 318," official Chrysler nomenclature describes it as the A479 or A-series 318.
Is 318 Mopar a small block?
Introduced in 1967 as a two-barrel engine with a bore and stroke of 3.91x3. 31, the 318 was an enlarged version of Chrysler's LA small-block that debuted in 1964 with 273 ci.
How much horsepower does a 318 small block have?
The 318 (5.2 Liter V-8) The power ratings of the new LA-series 318 were exactly the same as those for the old polyspherical-head design, 230 hp and 340 lb-ft.
What is a Mopar Poly 318?
The 318 is the most common version of the A engine, produced from 1957 through 1966 in the US and 1967 in some export markets when it was replaced in all markets by the LA 318. Only Plymouth used this 318 in 1957 and 1958, but it was shared with Chrysler from 1959 on and Dodge from 1960 on.
How much HP can a stock 318 handle?
A street-worthy 318 can easily make 400 horsepower, about what a lot of street 360s put out.
How many horsepower does a 318 motor have?
At introduction, the 318 had 230 horsepower at 4400 RPM and 340 LB-FT of torque at 2,000 RPM. Horsepower and torque also fell off during the 1970s to 145-155 HP at 4,000 RPM and 260 LB-FT at 1,600 RPM.
Can you put 340 heads on a 318?
The problem with all the 340/360 heads on a 318 is the chamber measures about 70 cc, which will drop the compression to an unworkable low ratio on a 318. You can forget about decent performance with these heads and the stock pistons, so again, a set of moderately priced aftermarket pistons is the answer.
What is a 318 magnum?
The 318 Magnum is an upgraded version of the LA 318 and was given the Magnum name by the marketing department. The 5.2 Magnum produced 230hp and 295 lb-ft. of torque. It's bigger brother, the 5.9 Magnum, produced 250hp and 350 lb-ft.
What size is a Dodge 318 motor?
Displacement: 318 cu in (5.2 L)
What are Polyspherical heads?
The Polyspheric or Poly engines were V8 engines produced by Chrysler from 1955 to 1958 as lower-cost alternatives to the Hemi engines. These engines were based on the Hemi engines, using the same blocks and crankshaft parts, but completely different cylinder heads, pushrods, exhaust manifolds and pistons.
What is a Mopar engine?
What Is a Mopar? Used colloquially, "Mopar" means any Chrysler, Plymouth, Dodge, DeSoto, Ram, or Jeep vehicle, with an emphasis on classic or vintage models. Mopar is the original-equipment replacement and aftermarket accessory parts division of Stellantis car brands distributed in North America.
What is a 318 magnum?
The 318 Magnum is an upgraded version of the LA 318 and was given the Magnum name by the marketing department. The 5.2 Magnum produced 230hp and 295 lb-ft. of torque. It's bigger brother, the 5.9 Magnum, produced 250hp and 350 lb-ft.
What is a Mopar engine?
What Is a Mopar? Used colloquially, "Mopar" means any Chrysler, Plymouth, Dodge, DeSoto, Ram, or Jeep vehicle, with an emphasis on classic or vintage models. Mopar is the original-equipment replacement and aftermarket accessory parts division of Stellantis car brands distributed in North America.
How much does a 318 engine weigh?
EngineWeightMopar 273-318-340 "LA" V8525Mopar 360 "LA"550Mopar 350-361-383-400 "B" V8620Mopar 413-426W-440 "RB" V867017 more rows•Dec 16, 2017
Is the Dodge 360 a good engine?
The Mopar 360 can make an excellent performance engine. It was introduced with a 2-bbl carburetor in 1971. Not intended as a performance engine, it also featured a cast crankshaft and low compression ratio (8.5 to 1) cast pistons.
MuuMuu101 Well-Known Member
So, this is for theoretical purposes. I know I asked on here and/or moparts before about boring a 273 to 340 specs and people said it shouldn't be done due to I believe the webbing between the cylinder walls. They said the 273 and 318 are similar and the 340 and 360 are similar.
replicaracer43 Grumpy Old Man
No, get a 318 block if you wanna do that, there can usally be had for free.
replicaracer43 Grumpy Old Man
Remember one VERY important thing about making horsepower, it requires STRAIGHT and ROUND bores, that stay that way under LOAD. Anytime you max bore a production block, your doing it the wrong way IMO.
MuuMuu101 Well-Known Member
Remember one VERY important thing about making horsepower, it requires STRAIGHT and ROUND bores, that stay that way under LOAD. Anytime you max bore a production block, your doing it the wrong way IMO.
grumpuscreature Resident Curmudgeon
Nice idea but there is one fly in the ointment. Ma Mopar in her infinite wisdom used different water jacket cores in each block in her efforts to make each one as light as possible. The cylinder walls in each block does not have enough thickness to allow much more than .060" overbore.
MuuMuu101 Well-Known Member
Nice idea but there is one fly in the ointment. Ma Mopar in her infinite wisdom used different water jacket cores in each block in her efforts to make each one as light as possible. The cylinder walls in each block does not have enough thickness to allow much more than .060" overbore.
JBurch FABO Gold Member FABO Gold Member
Interesting idea..........now here's one to chew on Call up Darton Sleeves, see if they could come up with a max bore sleeve kit similar to what they have for the 3rd gen Hemi then ANY LA block could go out to max bore......and with a good poker face, say it's just a good running 273, 318.....show them the casting number on the side of the block for proof..
Which is more powerful, the 340 or the 318?
the bored, which made the 340 far more powerful than the everyday 318.
When did the 318 have a four barrel?
In California and some high-altitude locations, 1979 cars with the 318 had a Thermoquad four-barrel to boost performance in the face of primitive emissions systems; starting in 1981, the four barrel was available in trucks regardless of location.
What is a wedge head?
The wedge heads (first used by Chrysler on the B engines) were far smaller, and lighter, than the old Hemi and polyspherical heads (318s with the poly heads are still often called "wide blocks" though the block itself is about the same size as that of the LA 318).
How much horsepower does a 318 have?
Horsepower shot up dramatically, from 170 to 230 hp, and the 280 lb-ft of torque stayed constant. That put the 318's power well above its best carburetor days. (The 360 had to wait a year, gaining Magnum power in the 1993 trucks and vans.)
What parts did the 273 carry?
The 273 carried over the A engines' crankshaft, bearings, bearing caps, vibration damper, and timing chain, and connecting rods ( other LA engines used different rods).
How big are the push rod guides on a Chrysler?
Since the pushrod angle was slightly changed by the taller lifters, the push rod guide holes were changed from roughly 0.5 inches to 0.66 inches. The push rods became shorter, and their diameter shrunk from 0.360" to 0.3125".
How many barrels are in a Carter BBD?
design that had dedicated one barrel of the Carter BBD two-barrel carburetor to each bank. This
What are the three key areas of a 318?from motortrend.com
Other than areas remedied by the usual bolt-ons, the factory setup fell short in three key areas: compression, camshaft, and cylinder heads.
How much horsepower does a 318 have?from motortrend.com
Power Squeeze While 400 hp from a bolt-together 318 may seem like plenty, we figured with a little go-fast gas our little engine could go hunting for some big-block game. With the hypereutectic KB pistons, we decided to keep the nitrous moderate and sane, just enough juice to stalk some of the hardier street beasts we may encounter. Be aware that KB has very specific ring end gap requirements for nitrous use, and these must be followed during the build if any kind of life expectancy is to be had from the engine with nitrous. We selected a Nitrous Works jet-metered plate system, a quick and easy addition to any engine. The plan was to add 100 hp to our normally aspirated output, not an excessive amount, but enough to really notice.
How many bolts does a magnum have?from motortrend.com
Along with these changes, the Magnum castings have a revised head bolt package that does not interchange with earlier engines. At the valve cover, the machined valve cover rail takes 10 bolts rather than the LA engine's five, though the earlier valve covers will still bolt on.
How long is a Magnum head pushrod?from motortrend.com
Magnum heads oil the valvetrain through the pushrods. We ordered Comp's 5/16-inch pushrods (PN 7960), which had the exact 7.650-inch length needed in our engine using the flat tappet hydraulic cam.
What pistons are needed for a 318?from motortrend.com
Piston choice is a critical aspect of any build, and in the case of the 318 the choices are limited. Our requirements were a flat-top piston at zero deck, which would provide a desired boost in compression ratio, while also ensuring that we would have an ideal quench clearance to make the most of combustion efficiency. Stock and stock replacement pistons place the pistons so far down the hole, that even with massive milling, the goal of a zero deck is out of reach. Fortunately, Keith Black offers a hypereutectic 318 piston that fits our criteria (KB 167). The assembly can be brought to zero deck with modest block machining, and the pistons are a commonly available shelf part at a practical price. To provide the combustion seal and desirable friction characteristics, high-quality moly rings are needed. We looked no further than Federal Mogul's offerings, opting for their pregapped moly rings. Though file-fit rings can be had for our bore size, these rings are more in keeping with our requirement for moderate cost and a bolt-it-together assembly.
When was the Mopar 318 Magnum introduced?from hotcars.com
As the 1990s came around, the 318 needed an update, and in 1991 the 318 Magnum was introduced, offering a new block and heads for extra efficiency and power. This engine was used through 2002, and while the 318 Magnum was only used in Dodge trucks, Mopar enthusiasts loved the feel of the old school 318, now updated for modern applications.
Is a Mopar 318 good?from motortrend.com
The Good And The BadIn terms of durability, the Mopar 318 is robust. The bottom end of most 318 engines used a cast-iron crankshaft, and though these are not as desirable as a forged crank, the cast-iron piece has proven to be very reliable. Early 318 engines (up to 1972) used lightweight rods with full-floating piston pins, while later engines were equipped with the heavier 340/360 forgings with press pins. The later rods are considered stronger, and this bottom end has proven very reliable in high-performance applications-especially in the street rpm range up to 6,500.