Mopar LA Series Engines
3.9 - 5.2 - 5.9 - 273 - 318 - 340 - 360 - 488 V10
Thanks to Bill Watson, Joshua Skinner, Carl Payne, Dan Stern, Steven Havens, Jim Forbes, and Peter Duncan for their contributions.
Looking for the “original” 1960s 318? Click here for the A-engines.
The LA engines were modern, relatively efficient, and extremely durable designs that became the mainstay of Chrysler's cars and trucks for decades - a fact which would probably have surprised their designers, given the pace of engine development at the time. A dizzying variety of engine variations were being produced in the 1950s and 1960s, steadying out in time so that the 318 and 360 cubic inch sizes remained for over thirty years each. The basic design is still in use, in the 505 cubic inch Viper V-10, though the V8 and V6 varieties have finally been replaced (they lasted into the 21st century!). There also remains a racing-only LA-based four cylinder - click here for details.
| Engine | Years (USA)* | Stroke | Bore | ![]() |
|---|---|---|---|---|
| 3.9 | 1988-2003 | 3.31 | 3.91 | |
| 273 | 1964-69 | 3.31 | 3.63 | |
| 318 (5.2) | 1967-2002 | 3.31 | 3.91 | |
| 340 | 1968-73 | 3.31 | 4.04 | |
| 360 (5.9) | 1971-2002* | 3.58 | 4.00 | |
| 488 V-10 | 1991 - 2002 | 3.88 | 4.00 | |
| 505 V-10 | 2002 - | 3.96 | 4.03 | |
| * “They ended up putting the 360 engines in a few of the trucks in January and February 2003.” — Rovell Rangel |
||||
The A was produced from 1955 through 1966, the LA from 1964 on; the LA was a modified version, with the most obvious difference between the lightweight (hence "L"A) or thin-wall casting and heads. The difference, about 50 pounds overall, was significant enough; but the LA was also considerably smaller, so that the 273 (the first LA) could be stuffed into the small Valiant engine compartment. The A engines' poly heads were wider and heavier than the LA's wedge-shaped combusion chamber; the LA's valves were simpler too, saving money and size. In the end, the 273 was only about fifty pounds heavier than the slant six!
Bill Watson wrote: "The LA 273 used the poly (A) 318 crankshaft, bearings, bearing caps, vibration damper, and conecting rods. The 273 and 318 both had a 3.31" stroke. Pistons were different, though, as the LA bore was smaller; and camshafts could not be shared due to the different valve arrangements. They did share a timing chain."
LA engines: 273, 318 (5.2), 340, 360 (5.9), 3.9 V6; related to V10
Click here for an article on upgrading the performance of LA engines
Putting the 318 into a Toyota Celica
The 3.9 liter V6: LA V6 engine (based on the 360)
Click here for the four-cylinder LA racing engine (no, that's not a typo!)
Interview with an LA engine designer, Pete Hagenbuch
The LA family was introduced in 1964 with the 273; the primary difference between the A and the LA was the new lightweight casting technique, which saved a great deal of weight (and was ahead of its time). In time, the LA would spawn a four-cylinder, V6, and V10, as well as both high performance and standard duty V8s, for both cars and trucks.
273: Designed for aluminum? (by Mike Sealey)
The first LA was the 273, with a two barrel carb, and 180 hp (gross). By 1965, a four-barrel carb and high performance cam were available to push that to 235 hp; and, in 1966, a limited edition 273 with a 700 cfm carb and .500" lift cam put out 275 hp (gross).
There
is some evidence, now lost in antiquity, that the 273 was not only
originally meant to be an aluminum-block engine but that it was also
meant to power a stillborn A-body DeSoto. Motor Trend and other
enthusiast magazines have long had columns where rumors of future
products are discussed and sometimes speculated on. Several of these
mentioned the development of both compact Dodges and DeSotos (bear in
mind that while Valiants
were sold by Plymouth dealers in the US, they did not take on the
Plymouth name until the 1961 model year) and a V8 engine sharing many
internal parts with the 318, but displacing about 270 cubic inches and
making use of an aluminum block.
Motor Trend even came up with artist's conceptions of the proposed Dodge and DeSoto compacts. It would apear that MT had some excellent sources inside Chrysler. Their sketch of the Dodge accurately predicted its use of the "Lancer" name, its grillework, and the character line that curves back toward the front of the car in the middle of the front door on production Lancers. The taillight and rear fender treatment looked rather more like that of the fullsize '60 Dodge Polara/Matador than what actually went into production.
The DeSoto sketch showed what was clearly a Valiant-based car, with a grille that widened at the bottom and extended under the headlight clusters much like the fullsize '60 DeSoto, and a taillight treatment clearly modeled off the Valiant/Lancer rear fender, but with three small lights in a row along the fender edge, paying homage to what had by then become the traditional DeSoto three-light fin treatment. MT speculated that this new compact DeSoto would carry the name "Adventuress". While this would have made for a slick tie-in to the larger, sportier Adventurer not unlike Studebaker's "bird" connection between Hawks and Larks, I personally doubt that with gender attitudes being what they were at the time DeSoto would have gone with something that overtly feminine. (Especially after the tiny number of Dodge LaFemmes sold just a few years earlier.)
| 1967 | 273 V8 (2-barrel) | 273 V8 (4-barrel) |
| Manual Transmissions | 3 or 4 speeds | 4 speeds |
| Horsepower (gross) (Valiant) | 180 @ 4,200 | 235 @ 5,200 |
| Torque (Valiant) | 260 @ 1,600 | 260 @ 4,000 |
| Bore and Stroke | 3.63 x 3.31 | 3.63 x 3.31 |
| Compression Ratio :1 | 8.8 | 10.5 |
| Standard Tire/Wheel | 7 x 13 (wheel 4.5) (Valiant) | |
I've never been able to confirm my belief that the similarly-sized aluminum-block V8 discussed for the stillborn compact DeSoto evolved into what we came to know as the 273 and the LA engines that followed, but there is circumstantial evidence that supports this theory. Preproduction lead times (and the notable differences between the A and LA engines, particularly in regards to head and intake/exhaust system design) being what they are, development of the 273 would have had to start around 1959-60.

Aluminum engine blocks were seen as the Big New Thing in this era, and while many remember the Corvair's extensive use of aluminum and the more conventional Buick/Olds/Pontiac aluminum-block 215 V8, relatively few remember the extremely brief production of aluminum blocks by manufacturers other than GM. Chrysler made an aluminum-block Slant Six as an option, apparently only in 225 configuration. While these aluminum sixes were in production, it would be safe to assume that aluminum V8s were also under development, if for no other reason than to compete with the senior GM compacts.
Jim Deane added: The intake manifold was special hybrid single/dual plane design that incorporated two plenums, one for each side of the engine. They were joined by a specially sized rectangular passage that solved lean/rich problems that occurred with the initial, purely dual plenum design that dedicated one barrel of the BBD to each bank. This was done to reduce the overall height of the engine and allow installation in the (originally /6 designed) Valiant engine compartment.
In 1978, Chrysler noted with regard to the 318 and 360:
Exhaust-valve seats are induction-hardened on all engines to allow satisfactory use of lead-free fuels. In the hardening process, seats reach a temperature of 1700°F and are then allowed to air-cool. This hardens the valveseat surfaces to a depth of .05" to .08" which gives them greater resistance to wear than unhardened seats.
The exhaust-valve stems on all Chrysler engines built in North America are chrome-plated for increased resistance to wear.
The heat valve in the right exhaust manifold diverts hot gases to the floor of the intake manifold which helps to vaporize the fuel mixture when the engine is cold. This results in faster warm-up and improves driveability after a cold start. During warm-up, a thermostatic spring allows the heat valve to open to the exhaust pipe-so gas flow through the intake manifold crossover passage is decreased.
All 1978 Chrysler V-8 and 6-cylinder engines have an adaptor to receive a magnetic probe for timing the ignition magnetically. The adaptor is a little steel sleeve attached to the bracket that has the traditional timing marks-you can still set the ignition with a timing light. However, ignition timing is being set magnetically on all engines at the factory - because magnetic settings are more accurate than those made with a timing light. The magnetic timing adaptor will also help those dealerships who have the electronic diagnostic equipment necessary to time V-8 engines with the Lean-Burn System magnetically.
The 318 (5.2 Liter V-8) - Poly, Magnum, etc.
In 1967, the new 318 came along, with a 3.91" bore rather than the 273's 3.63" bore. The Mopar V-8 Engines book describes it as being like a short deck, lighter version of the original 318. According to Mark Koskenmaki, all 1967 A-type 318s came from Canada, while vehicles built in the US had the new LA 318.
| 1968 specs (Valiant) |
273 V8 | 318 V8 | 340 V8 (Barracuda) |
383 V8 (Barracuda) |
|---|---|---|---|---|
| Gross Horsepower | 190 hp at 4400 rpm | 230 hp at 4400 rpm | 275 hp at 5000 rpm | 290 hp at 4400 rpm |
| Torque, lbs.-ft. | 260 at 2000 rpm | 340 at 2400 rpm | 340 at 3200 rpm | 390 at 2800 rpm |
| Compression ratio | 9.0 to 1 | 9.2 to 1 | 10.5 to 1 | 9.2 to 1 |
| Bore, inches | 3.63 | 3.91 | 4.04 | 4.25 |
| Stroke, inches | 3.31 | 3.31 | 3.31 | 3.38 |
| Displacement, cu. In. | 273 | 318 | 340 | 383 |
| Carburetor type | 2-bbl. | 2-bbl. | 4-bbl. | 2-bbl. |
| Air cleaner type | Silenced | Silenced | Unsilenced | Silenced |
| Exhaust | Single | Single | Dual | Single |
| Camshaft | Standard | Standard | Special | Special |
| Fuel | Regular | Regular | Premium | Regular |
Chrysler actually made three basic versions of the 318: the first, polyspherical-head version in the 1960s - the second, LA family in the late 1960s and through to the late 1980s/early 1990s - and the final Magnum family, which is still in production for light trucks and Jeeps. The 318 may be discontinued as the first completely new Mopar V-8s since the 1950s are introduced.
The
318 came as the standard V-8 for many years, and was the optional V-8
on Valiants and other small cars in its earlier years, when the 273 was
still around. It was used as a police engine, mainly in the M-bodies
(Diplomats and Gran Furys), and was often the largest engine available
in Valiants and their descendents, the Volare/ Aspens and Diplomat/Gran
Furies.
From its introduction in 1967 through its conversion to EFI, the 318 was generally treated as a two-barrel workhorse. With the 340 and 360 around, the 318 kept its "economy carb" from 1968 through 1978, when it got a four-barrel option. Despite its "economy engine" status through many years, the 318 started out as a performance option and ended as one in Chrysler's final police cars, the M-body Diplomat and Gran Fury. (Unfortunately, without rear-wheel-drive sedans to put them in, the Magnum treatment never made it into the police force).
Though the 318's performance came between the GM 305 and 350, it never seemed to have the oil-burning and smoke-producing qualities of those engines. Like the slant six, the 318 has shown itself capable of great abuse at the hands of those non-oil-or-air-filter-changing folk who so often end up behind the wheels of Mopar cars and light trucks.
| 1973 Valiant Engines | 318 | 340 |
|---|---|---|
| Bore x stroke | 3.91 x 3.31 | 4.04 x 3.31 |
| Carb | 2-barrel | 4-barrel |
| Compression ratio | 8.6:1 | 8.5:1 |
| Horsepower @ rpm | 150 @ 4,000 | 240 @ 4,800 |
Rather than coming to the same (performance-oriented) end as the 305/350, though, the 318 was destined to be phased out of cars entirely, and to be used in pickups and Jeeps. Though the modern version has been raised to its potential, with sufficient fuel making its way into the cylinders and more efficient burning, the 318 was rarely really fully appreciated by Chrysler (the pre-1972 340 years are a major exception).
| 1976 figures | Slant Six Valiant | 318 V8 Valiant | 360 V8 Valiant | 440 Fury |
|---|---|---|---|---|
| Low speed pass | 475 feet / 11.0 sec | 460 feet / 10.5 sec | 405 feet / 8.6 sec | 400 feet / 8.4 sec |
| High speed pass | 2090 feet / 24.8 sec | 1480 feet / 16.2 sec | 1245 feet / 13.3 sec | 1130 feet / 11.7 sec |
In 1978, Chrysler wrote this about the 318:
“Chrysler's most compact V-8 designed to be rugged and dependable - is equipped with the second-generation Electronic Lean-Burn System for 1978. Features include:
- Hydraulic valve lifter (tappets)-no periodic adjustments required
- Induction-hardened exhaust-valve seats
- Cast ductile iron crankshaft
- Single exhaust system with catalytic converter
- Aluminized steel exhaust and tail pipe
“The 318 V-8 has proved its reliability over the years as the number-one best seller in Chrysler Corporation's lineup of V-8 engines. Now, it offers the increased dependability of electronic spark-plug timing and ignition controls. (A four-barrel version to meet California emission requirements is available on LeBaron and Cordoba in California).
“[It now has a] lightweight carburetor-over a half pound lighter than the previous carburetor-is designed for solid-fuel operation. This means a solid, continuous stream of fuel is fed to the primary discharge nozzles by the metering system. The fuel is mixed with air upon entering the nozzles. The solid-fuel metering produces precise carburetion for good driveability with lean fuel-air mixtures.”

In 1980, Chrysler advertised the following specifications:
Bearings, Camshaft—Steel-backed Babbitt, five, replaceable
Bearings. Connecting-Rod, Lower—Aluminum on steel.
Bearings, Crankshaft, Main—V-8: five babbitt (except #3 aluminum), replaceable. Oil grooves in upper and lower # 1 bearing, in upper half of all others.Journal
Dimensions 1
2.50" x 0.872"
2
2.50" x 0.872"
3
2.50" x 1.51V
4
2.50" x 0.872"
5
2.50" x 1.322"
318 throttle-body / roller-cam engines (by Vince Spinelli and Jack Perkins)
The throttle-body fuel-injected 318 motor had a few changes for its model year (1988) [which would come to the 360 in 1989].
First, Chrysler finally switched from standard hydraulic lifters (and matching camshaft) over to a roller hydraulic lifter (and thus a new matching camshaft). The roller design allowed for a steeper cam profile, and thus a more precise valve-train actuation.
Second, no more carbureted intake – but the 2 barrel TPI fuel injection intake. [Webmaster note: the company was still intent on cost savings, and six more fuel injectors per engine does add up; still, others had been using multiple-port injection for some time — it had been standard in the Volkswagen Rabbit since 1979.]
Third… the heads are different; while the basic casting is the same, the fine points are not. To make better use of the benefits of fuel injection, swirl intake ports were introduced. Also, to accommodate a slightly changed pushrod angle (the new roller lifters were taller than the previous standard hydraulics) the push rod guide holes in the cylinder heads were changed from roughly 0.5 inches to a published 0.66 inches (Dodge DW Series Truck Factory Service Manual 1988). Upon measurement, this was confirmed to within an accuracy of 0.01 inches. Push rod length changed from about 7.5” down to 6.78”, and diameter shrunk from 0.360” to 0.3125” (again to accommodate the changed push rod angle).
[See the Magnum section, later in this page, for details on the "5.2" or 318 Magnum engines.]

318 Engine Troubleshooting
Duane D. Hughes wrote:
A couple of tips for 318s with Carter 2 bbl carbs:
Mine was a 1976, and it stumbled and sagged badly from the time it was started until it was fully warmed up It did this from the time it was new. This is a classic sign of a too lean mixture. I happened to have a friend who worked in the service department of a Dodge dealer, and he advised me to raise the metering rods about 1/16 th of an inch. This can be done without disassembling the carb. Just add the additional 1/16th inch rise, and you'll cure your problem. I did this on my car, my dad's 1976, and my uncle's 1977. Worked in every case.
Another problem I had with that car was pinging at light, not heavy load. It would ping on the slightest grade at highway speeds. One day I happened to read that truck 318s had an adjustable vacuum advance on the distributor, accessible through the little hole where the vacuum line attaches to the vacuum advance unit. I fooled around with various Allen head wrenches until I found one that seemed to grab something. Sure enough, a screw to adjust the advance. Just a little playing around to get the right setting, and Voila! No more pinging. No change in mileage, either.
From: Bruce Martin wrote: One very common fault with the otherwise wonderful 318 is that the exhaust crossover in the intake manifold (which warms the base of the carb) becomes clogged. This is common so it should be among the first things you check. (This problem was addressed on the Magnum engines)
Curt Pinck wrote: It is interesting the wide variety of timing specs given for the 318, all the way from 2 degrees ATDC to 16 degrees ATDC, depending on the type of engine and vehicle...Most books recommend not to try to time by ear, even if you have experience doing this.
Ted Devey adds two more steps:
- Examine the reluctor teeth in the distributor for possible damage, nicks etc. which can happen if the gap gets too small. If there is damage to the teeth, replace the reluctor.
- Several years ago I dismantled the Carter 2-barrel carburettor and reassembled it with the jet assembly upside down. There is no obvious wrong way.
The 340: high performance in a small package
Probably the best development for performance enthusiasts was the production of the 340 V-8 in 1968. It had high-flow heads, big ports, a two-level intake manifold, and a six-barrel option (three two-barrel carbs).
Click here for a full page on the 340.
There were many differences between the 340 and 318 apart from the bore of a similar block. The 340, from '68 to '71 at least, is the smallblock equivalent of the Hemi. It has great power when put in the right car (a '68 Barracuda, for example), and has more than enough appeal to keep the Brand-X guys wishing they'd boarded the Mopar Express before the light turned green.
The 360
The 360 first appeared in 1971, with a two barrel carb. It has a lot of lesser qualities, the primary one being a cast crank and external balancing. It also has the distinction of being the only LA engine without a 3.31" stroke (3.58").
The 360 was relatively tame through 1974, when it received some 340 performance parts and a four-barrel carb. In recent years, the 360 has been Chrysler's performance truck engine, making the Grand Cherokee 5.9 Limited the fastest SUV and powering top-of-the-line Dakotas and Durangos. For some time, the 360 was also used as a 340 substitute in vehicles such as patrol cars and the Volare Roadrunner. In 1987, a number of 360s were used in Diplomats and Gran Furys; some say that some of these engines were labelled as 318s, but that's a tough one to track down.
Vince Spinelli and Jack Perkins added: “There are squad car heads, and there are interceptor heads. Squad car (cruiser) heads are 360 heads with little to no modification depending on whom you talk to. Interceptor heads are high compression heads, identical in every way to standard 318 heads of the era, but with a smidge tighter combustion chamber. Compression works out to high 9s to 1, as opposed to the standard 318 head at about 8.5 to 1. Interceptor heads also have slightly large valve aperatures.”
Dave Lyle expanded on this: “The heads that came in cop cars were J heads, and they were essentially the same as regular 360 heads, except for bigger intake valves (1.88) and better springs.”
In 1978, Chrysler wrote: “This is a larger displacement version of the compact 318 V-8. The cylinder bore is 4.00" (compared with 3.91" for the 318), and the stroke is 3.58" (compared with 3.31" for the 318). The extra displacement gives the 360 V-8 more horsepower and torque than the 318. Valve timing, valve lift and length of time the valves remain open are carefully engineered for low emissions, power, and smooth operation at all speeds. Hydraulic valve lifters require no periodic adjustments. This engine has a single exhaust system. The camshaft is designed to seat the valves smoothly to decrease the possibility of valve bounce and the stress it causes in valve stems.” In 1978, the 360 gained dual concentric throttle return springs in addition to a torsion throttle spring.
The 1978 California version “comes equipped with an air pump as well as a catalytic converter. It can be ordered for use at low altitudes and outside the state of California, but only with the N96 emission-control package. All versions of this engine are equipped with a single exhaust.”
See the 318 section for changes to the 360 in 1989, when it switched to roller cams and throttle-body fuel injection; and see the Magnum section, later in this page, for details on the "5.9" or 360 Magnum engines.
All 360 production was moved in Mexico in 1980, according to Rodolfo Rodriguez. United States use of the 360 ended in December 2002.
Across-engine specifications

Identifying LA Series V-8 engines and parts interchange
LA engines have the distributor at the rear, and the displacement is on the left front o the block, below the left cylinder head. Unlike the A engines, which have the valve covers held on by two bolts in the middle, LA valve covers are held on by five screws on the outside of the covers. If you remove the valve covers (the gaskets tend to go after 10-20 years), do not tighten these screws too far, and follow the instructions for 2.2 valve cover replacement in the FAQ. (Except that you will use a rubber gasket, available at low cost from your local Mopar guys, instead of RTV alone).
Robert Jones wrote: "All head gaskets for 318 ci LA series engine made by aftermarket (and I'm sorry to say even chrysler) are made to fit all bore sizes ranging from the 318 to 340. The fire ring is so much larger on a 340 and the gasket thicknes is closely matched to a 360 spec gasket that the compression is significantly reduced. Example: 1976 Plymouth Volare factory timing spec was 2 degrees (in Canada... was very snappy) and after I had changed the gaskets I found I couldn't make it ping even with as much as 10 degrees advance whereas 6 degrees was almost undriveable."
Dave Wordinger wrote: "The 1964-1965 273 head had the had the intake manifold bolt holes drilled at a different angle than the other LA heads, but will bolt to any LA block. The 1970 340-6 had the pushrod holes relocated. All other LA heads are interchangeable. The heads don't care what kind of camshaft or lifters you are using. The 1964-1967 273 had mechanical lifters. All 1968 and newer LA engines had hydraulics."
David William Elder wrote: "If you compare an early (such as 68) 340 crank to a 318 crank of the same vintage you can clearly see the 340 casting is beefier. I think the two are the same numerically speaking but as far as sheer strength the 340 is clearly the winner. The same goes for the connecting rods. The 273-318 connecting rods are similar to the 340s but definately a different casting with less 'beef'. I have actually seen some mid-70s truck and stationwagon 318s that came from the factory with 340-6pak rods."
Mark DuVerger wrote: "The 273 rods are not the same as a 318, they measure the same and look identical but are in fact a lighter rod. Also all 273 rods are full floating rods, 73 and up 318's are press fit rods for the wristpin. Just a note if you ever had or ran a 273 you can notice the difference in the way it performs it will rev alot faster than a 318, or a 340."
Ed Prichard wrote: "Basically any intake that fits a 318 (LA engine) will also fit a 273. They will also fit 340s and 360s as well. But it is easier to find a "non-smog" intake for a 273 or 318 than a 360."
See the starter page for information on starter interchangeability.
Magnum Engines (318/5.2, 360/5.9, 3.9 V6)
Thanks to Carl Payne
The main differences to the "new" 5.2l and the "old" 318 are in the block and heads. The new block affords roller lifters, yes it has changed lifter agle for same, and has bosses for the lifter retainers. The heads are high-swirl / high-flow heads, though not the old "X" heads of the 340, and obviously the Magnum has that cool intake. the "new" 5.2l came about in changes made in '87, which were fully incorporated by '90. The changes were made to facilitate a more common creation of the 5.9, 5.2, and 3.9 V6 engines.
Webmaster note: with the Magnums came more standardized parts between the 318 and the 360, mainly to the benefit of the 318. The 360 has seen new life in a special edition Jeep Grand Cherokee and the new Durango. The "Next Generation" V8 family produces similar power with less weight, fuel use, and emissions, though durability is unknown. I'll miss the LA family's low-end grunt and long life, but the new engines seem to rev more freely, are more efficient, and may be as bulletproof.
Gary Howell wrote: "The Magnum 318 and 360 engines are LA engines with different cylinder heads. The blocks are physically the same as the earlier LA engines, except the oil passage for the shaft mounted rockers is not drilled, because the Magnum engines oil through the push rods. The boss is there if you need to use the old style heads."
LA Series Components
(Thanks to Stephen Havens)
Heads
273 int 1.78" exh 1.50"
318 with 2bbl same as 273
340 X heads 2.02 1.60
360 all including J head 1.88 and 1.60
Camshafts
| Engine | Setup and cam | Lifters | Lift | Duration |
|---|---|---|---|---|
| 273 | 2 barrel through 67 | Mechanical | 395/405 | 240/240 |
| 273 | 2 barrel 68-69 | Hydraulic | 373/400 | 240/248 |
| 273 | 4 barrel | Mechanical | 415/425 | 248/248 |
| 318 | 2 barrel 67 | Hydraulic | 390/390 | 244/244 |
| 318 | 2 barrel through 88 | Hydraulic | 373/400 | 240/248 |
| 318 | 4 barrel | Hydraulic | 430/444 | 268/276 |
| 318 | roller cam | 391/391 | 240/240 | |
| 340 | 4 barrel 68 man trans | Hydraulic | 444/453 | 276/284 |
| 340 | 4 barrel | Hydraulic | 430/444 | 268/276 |
| 340 70 | six pak | Hydraulic | 430/444 | 268/276 (adjustable rockers) |
| 360 | 2 barrel 71-74 | Hydraulic | 410/412 | 252/256 |
| 360 | 2bb 75-up | Hydraulic | 410/410 | 252/252 |
| 360 | 4 barrel | Hydraulic | 430/444 | 268/276 |
Carburetors
- 273 4V is AFB
- 78-85 318 is Thermoquad
- 86-91 318 is Quadrajet
- 68-70 340 is AVS
- 71-73 340 is Thermoquad
- 74-85 360 is Thermoquad
- 86-92 360 is Quadrajet
- 273 2bbl is Carter BBD 1 1/4"
- 67-73 318 is BBD 1 1/4" ( in 72 318 with A/C got Rodchester 2GV)
- 74-91 318 Holley clone of BBD 2GV and BBD were all used, though no BBD past 85
- 71-92 360 Carter BBD 1 1/2" and Holley clones post 85 maybe some Rochesters
Relevant LA V8 engine links
- LA predecessors: the A-engines
- Speaking to the engine architect: Willem Weertman
- Speaking to an LA-engine engineer: Pete Hagenbuch
- Upgrading your LA (273, 318, 360)
- 318 and 360 specifications for squad car use, 1967-1976
- Repair tips
- Performance tips
- Allpar (Chrysler and Dodge enthusiast site)
- Mopar Engines
- The Valiant Pages
- Books:
- How to Hot Rod LA Engines (318, 273, 340, 360, 1965 - 1989) - 20% off
- How
to Hot Rod Small Block Mopar Engines : Covers All Chrysler, Dodge &
Plymouth LA Series Engines-1965 to Present-273-318-340-360 C.I.D. ~ Larry Shepard / Paperback / Published 1989 - Our Price: $14.36 ~
You Save: $3.59 (20%) - How to Rebuild Your Small Block Mopar ~ Taylor, et al / Paperback / Published 1982
Our Price: $14.36 ~You Save: $3.59 (20%)
Chronology of the LA series Chrysler V8 engines
(Thanks to Stephen Havens)
- In 64 1/2 the 273 was released as a new lightweight compact V8 for the A-body, requiring notches in side of block to clear the power steering pump. It had 2bbl mechanical cam forged crank and 8.8:1 pistons.
- 1965 - 273 recieves more agressive cam and 4bbl with 10.5:1 pistons; these will remain through 1966.
- 1966 - bolt angle on the intake changes; 64 and 65 heads and intake are unique.
- 1967 - 318 released with hydraulic cam, forged crank, 2bbl carb, 9 : 1 pistons; truck motors recieve water heated intake with no exaust crossover.
- 1968 -
- 273 gets hydraulic cam and loses forged crank
- 4bbl 318 loses forged crank
- no more water heated intake on trucks
- 340 released with forged crank, 4bbl, hydraulic cam (in 1968, only the 4 speed cars got a more agressive cam in the 340, automatic cars got a cam that the next year would become standard in high performance small block mills). New heads, larger ports and valves first year for the dual plain intake 4bbl only.
- 1969 - last year for the 273
- 1970 - 340 gets Six-Pak, revised pushrod holes on these J heads for more meat in the intake runners. Also, T/A blocks with thicker webs for the ability to install 4 bolt mains on 2 3 and 4.
- 1971 - 360 released, 2bbl hydraulic cam, cast crank, J heads
- 1972 -
- 318 and 340 compression drops into the 8s
- 340 gets smaller valved J heads (previously all 340 except the six pack got X heads; Six=Pak J heads were machined for larger valves)
- 1973 - last year for 340, all 2bbl intakes become dual planes with EGR valves; before all intakes were single plane except 340 4bbl manifolds
- 1974 - 360 gets 340 cam carb and intake and is the new hi-po small block, dubbed the E58 police engine
- 1978 - 318 gets 360 heads, cam, intake, and carb; the E48 is born. The 318 gets a lighter carburetor with “solid fuel metering” and the 360 gets additional throttle return springs. Second Generation Lean Burn debuts on both. California cars get a four-barrel 318.
- 1983 - 318 police head released, larger than 360 combustion chamber, added water passages for cooling
- 1985 - (According to Blaze, Federal 318s went to a roller cam and lifters unless they had the four-barrel carburetor.)
- 1986 - 318 receives high swirl heads
- 1987 - 3.9 is developed from 360
- 1988 - 318 get hydraulic roller cam; 3.9 and 318 get throttle-body fuel injection
- 1989 - 360 gets hydraulic roller cam
- 1992 - Magnum appears on 3.9 and 318 (5.2)
- 1993 - Magnum 360 (5.9) appears
- 1999 - 4.7 V-8, the LA family's replacement, appears on the Grand Cherokee, with slow phase-in planned for other models (including V-10 and possibly V-6 derivatives).
- 2002 - The 318 is gone, leaving the 360 as a high-power option on pickups until the Hemi is available. A larger Viper V-10 replaces the original.
- 2003 - Truck V-10 cancelled; Viper V-10 continues the LA design into 2004, and is used in the Ram SRT-10.
- 2007 - Rumor says a new Viper V-10 will be introduced, worked over by McLaren.
R E L E V A N T B O O K S
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