1OldFordMan

Are a 318, 340, & 360 the same engine, just different internal specs.? Know a guy who is interested in turning a 318 into a 360. I always thought they were the same engine, but don't want to lie to the guy. Anyplace here with info. on building up a small block ( stroker kit or whatever )?

1966sportfury

they are the same for the most part...but you cant make a 318 into a 360 unless you got a stroker kit. the 273,318,318poly,340 all share the same crank. besides not all 340's were forged.. the 360 has a totally diffrent crank. and you couldnt bore a 318 LA to 4 inch bore.. the poly you can.

1OldFordMan

Thanks for the info. Didn't realize the 273s were the same, thought they were different being older. 318, 318 Poly? Sorry, don't know that much about Mopar ( I do know the most famous word, HEMI!!!!!!!! ). Seriously didn't know there were two different 318s although now that I think back, I remember the '64 Fury I once had ( yes, I have owned Mopar before & currently own an AMC ) was a 318. Don't think that was the same engine as the " modern " 318s. Had no complaints with them, just always been a FORD man. Actually joined here looking for a Mopar, couldn't find anything I could afford & then afford to fix. Almost had one, but changed my mind.

67 GTX

in 67, the 318 replaced the 273
the 318 poly was an early fifties-sixties engine

1OldFordMan

67GTX, thanks for the info. Didn't realize the 273 was still going that long. Thought they went away in the early '60s. So a 318 poly isn't the same as what they have now, correct? Actually, I guess now they don't even make 318 -360 anymore. It's all sillyliter & new Hemis isn't it?

67 GTX

not sure if mopar got rid of the 318's
i know up to a few years ago, they were making them
mopar now has pentastar engines and some phoenix engine coming out

1OldFordMan

Guess I was just going from what I hear in the truck ads on the radio. I know they call everything sillyliters now instead of cubic inches. Too old to learn all the new terminology. Pretty sure the 360 is gone, replaced by the new ( smaller ) Hemi.

dodgenut7

dont know if this correct but i was told the 3.9 is just like the 318 build wise just 6 cyls instead of 8 and the 4.7 is like a 360

sweeperking

FYI

5.9 converts to a 360
4.7 is closer to the 273 (actually converts to 286)
3.9 converts to a 238 (what ever that is)

1OldFordMan

Sweeper King, thanks for the info. Sure I've seen it before, just too old to remember it. Grew up with cubic inches & been cubic inches all my life. If I really try hard, I can sometimes get the more popular ones figured out in my head. ( FORD 5.0 actually is the good old 302, think the 351 is called 5.7 or something like that. Mopar 5.9 = 360. )

Mopar_71

Here's the info.... it's a lot but since you are a Ford guy, we need to get you up to speed.

Chrysler's small-block V8 engines all derive from the classic A engine:

• 1964½-1992 LA small-block - An evolution of the 1955 Plymouth A engine, using wedge-shaped instead of the prior polyspherical combustion chambers.
• 1992-2003 Magnum small-blockThe original LA design was almost totally revised for 1992 (318) and 1993 (360), with the only carry-over parts being the crankshaft and connecting rods. The only A/LA/Magnum-derived engine design currently in production is the Viper V10. (273/318/340/360)
• 5.7 L Hemi - The modern Hemi, introduced in 2002.
  • 6.1 L Hemi - A larger modern Hemi, introduced in 2004. Sometimes called the 3G or Gen 3 Hemi to distinguish from earlier Hemi engines.
• The 273 (4.5 L) was the first LA engine, introduced in 1964 and offered through 1969, rated at 180 BHp. It had a 3.625 in (92 mm) bore and 3.31 in (84 mm) stroke. It had a mechanical solid lifter valvetrain until 1968 when hydraulic lifters were introduced. A special version was also available in 1966 only - it used a 0.500-inch (12.7 mm) lift solid-lifter camshaft, fabricated-steel-tube exhaust, and a Holley 4-barrel carburetor, producing 275 horsepower (1 hp/cu in). It was available in the Dodge Dart only, and the car so equipped was called the "D-Dart".

The LA 318 was a 318 cu in (5.2 L) relative of the A 318. Like the A 318, it has a larger bore at 3.91 in (99 mm) as well as a stroke of 3.31 in (84 mm). It appeared shortly after the 273, in 1967, and proved tremendously successful. A version of this engine was available until 1991 when its was superseded by the Magnum version (See below). It used hydraulic lifters and a two barrel carburetor for most of its production. The 318 received roller lifters and a fast-burn cylinder head in 1985. Throttle-body electronic fuel injection was factory equipment on the 1981-1983

The 340
As the Detroit power wars heated up in the mid-1960s, Chrysler decided to produce a small block V8 specifically designed for high performance applications. The goal was to have a lightweight, high output engine equally suited for the drag strip or an oval track. The result of this decision was the 340 cu in V8. Chrysler's engineers increased the 318's cylinder bores to 4.04-inch (103 mm) while keeping the 318's 3.31-inch (84 mm) stroke. It fitted a forged steel crankshaft instead of the cast nodular iron unit used in the 318. A 4-barrel carburetor was mated to a high-rise, dual plane intake manifold. This induction setup fed into a set of cylinder heads that are still considered one of the best of that era. The heads were high-flow items with big ports, and used 2.02-inch (51 mm) intake and 1.60-inch (41 mm) exhaust valves. An aggressive cam was fitted to take advantage of the much better breathing top end. 1968 4-Speed cars got an even hotter cam, but it was discontinued in 1969. The engine was equipped with hydraulic lifters. Power output was officially stated as 275 hp (205 kW) for the 4 barrel and 290 hp (216 kW) for the 6-pack version with triple 2-barrel carburetors. Using flat-top pistons, the 340's compression ratio was 10.5:1, placing it near the limit of what was possible on pump gas. The 340 also used heavy-duty parts such as a dual timing chain, windage tray and revised oil pump.
In 1970, Chrysler offered a special version of the 340 for use in the Challenger TA and Cuda AAR. The "TA" engine featured a heavy duty short block featuring additional webbing in block to allow for 4 bolt main bearing caps, double roller timing chain and 10.5:1 compression. The heads featured larger ports compared to a standard 340 and offset rocker arms that allowed the pushrods to be moved away from the intake ports for improved airflow. They featured an aluminium intake manifold with three two barrel Holley carburetors and a dual points ignition system.
Like many other performance V8's of the day, for insurance reasons, the 340 engine's power output was officially understated. In reality, either the 4bbl or 6bbl configuration could produce at least 315 to 320 hp (235 to 239 kW). The 340 developed a reputation for outperforming much larger and heavier engines, with the attendant handling benefits provided by the relatively light-weight 340.
The 340 did not stay in production long. It was released in 1968, detuned with lower compression and smaller 1.88 inch intake valves in 1972, and was withdrawn from production after the 1973 model year.

The LA 360 (5.9 L) has a 4.00 in bore and a 3.58 in stroke. It was released in 1971 with a two barrel carburetor. The 360 used the large intake port 340 heads with a smaller intake valve (1.88 inch). In 1973, a 4-barrel version was released. In 1974, the 360 became the most powerful LA engine with the end of 340 production. After 1980, the 360 was primarily used in Dodge Ram trucks and vans. However, in some instances, the 360 was used in Dodge Diplomat police cars. The 1978-1979 Lil' Red Express truck used a special high performance 360 4-barrel engine, with factory production code EH1. The EH1 was a modified version of the E58 360 police engine (E58) producing 225 hp (168 kW) net @ 3800 rpm. Some prototypes for the EH1 featured Mopar Performance W2 heads, although the production units had the standard 360 heads. The 360 was replaced for 2003 with the 5.7 L Hemi.

The LA family was updated and branded as the Magnum V6 and V8 in 1992. While the Magnum 3.9, Magnum 5.2, and Magnum 5.9 (1993-up) engines were significantly based on the 239, the 318, and the 360 — respectively — many of the parts will not directly interchange and are not technically LA engines (the only parts that are actually unchanged are the crankshafts and connecting rods). Magnum cylinder heads use a different oiling system and individually mounted rocker arms (AMC style) and a CCW rotation water pump with a much improved housing. The intake manifolds share basic dimensions but will not interchange without modifications. Chrysler's engineers redesigned the oil seals on the crankshaft to improve anti-leak seal performance. Although the pre-Magnum ('71-'92) and Magnum versions of the 360/5.9 are both externally balanced, the two are balanced differently (the 360 Magnum uses lighter pistons) and each requires a uniquely balanced damper, flywheel, drive plate, or torque converter. The valve covers on the Magnum have 10 bolts rather than the previous 5, for improved oil sealing.
Chrysler offers a line of crate engines based on the Magnum designed to bolt into older muscle cars and street rods with little modification. Some of the changes to facilitate this were using a 1970-93 water pump so that older pulleys and brackets could be used, as well as an intake manifold that uses a carburetor instead of fuel injection. With a high lift cam and single plane intake, the crate Magnum 360 was rated at 380 hp (280 kW) with the Magnum heads. Later models equipped with "R/T" or aluminum cylinder heads produced 390 hp (290 kW). A 425-HP bolt-in fuel injection conversion kit is also available.

The Magnum 5.2, released in 1992, was an evolutionary development of the 318 with the same displacement. The Magnum development included the multiport fuel injection, new cylinder heads with a closed combustion chamber, a new higher-flow valve angle, increased valve lift, and new intake and exhaust manifolds. Power was up to 225 hp (168 kW) and 295 lb·ft (400 N·m). Production of the Magnum 5.2 ended with the 2003 model year Dodge Ram Van. It was replaced by the new 4.7 L PowerTech V8.

The Magnum 5.9 is an evolution of the 360. It got the Magnum V8 name with the same new manifolds, heads, and fuel injection as the 5.2 for 1993. Engine output that year was 230 hp (170 kW) and 325 lb·ft . The engine eventually produced 250 hp (190 kW) and 345 lb·ft on the version used in the Dakota RT. Starting in 2003, the 5.7 L Hemi V8 began replacing this engine.

1OldFordMan

Mopar 71, you were right. That was a lot of info. All of it excellent & pretty much what I was wondering. Thanks for all that. Now to see if I can figure out how to get all that to him. Did send him the www. thingie for here, he may look it up himself later. Again, thanks for a GREAT write up. Knew a little of what you said, didn't know the 273s were around that long or even a high performance engine. Always thought of them as older ( late '50s into early '60s ) & more of a grocery getter / grandma engine. I had the idea the 318s replaced them much like FORD did with the 289 / 302.

dodgenut7

hey sweeper what formula did you use to convert those to cubic inches i was just wondering also thanx for clearing that up for me off the top of my head those figures i was told just didnt seem right but like i said in my post i wasnt sure if they were right

sweeperking

http://www.metric-conversions.org/vo...bic-inches.htm

Maxy

Good advice here. But the only real differnce is a few vacuum connectons and the jetting in the carb.

bboogieart

between a poly, an L.A. or a magnum? I missed something huh?