1988 Chrysler, Plymouth, and Dodge cars: Engineering, technology, and features
The Mopar cars of 1988 (summary)
By 1988, most of the Chrysler, Plymouth, and Dodge cars could be described in two letters: K and L. Most cars (including the minivans) were based off the extended K-car platforms (hence the pet name EEK); the L-body Omni/Horizon still soldiered on, without the Turismo, O24, Rampage, and other variants, but it was soon to disappear without replacement (at least not as of 2006). The Reliant and Aries themselves were finally gone, and the M-body Gran Fury/Diplomat/Fifth Avenue stayed in production to service America's police and taxi fleets; the Colts continued, as they would until Chrysler's early-1990s rebirth. Under the placid waters of endless variations on the K platform (including a new, longer-wheelbase setup introduced in 1988), engineers worked on specialty variants, to appear with the Shelby or R/T tags. Not until the Viper would the corporation gain an entirely new vehicle; but the process that brought about the Viper would soon replace just about every vehicle Chrysler Corporation made, instigating a renaissance before the nightmare years and, hopefully, another renaissance.
The Chrysler TC by Maserati also finally arrived, built in Italy and shipped to selected dealers in small - smaller than desired - quantities. Intended to appear before the LeBaron GTS, which would be styled like the more expensive, exclusive TC, the TC showed up afterwards, making it look like a copy of a Chrysler, not the hoped-for effect.
Some standard features for 1988 included clearcoat paint, power brakes, dual hydraulic brakes, front wheel disc brakes (ventilated on most models), semi-metallic pads on front drive models, self-adjusting rear drum brakes, and electronic ignition. Chrysler also had a 7 year - 70,000 mile powertrain warranty.
Extensive anticorrosion treatments protected all North American-built cars. Even before the metal was formed into body panels, it was coated to protect against corrosion. Galvanized steel was used extensively for many body panels. And still other panels were coated with zinc-rich primer, which retains its integrity even after forming or stamping.
When assembled, each car body was thoroughly cleaned and coated with special chemicals in a 7-step dip-and-spray process for additional protection against all forms of corrosion (see later in this page).
Engineering highlights
Fuel injection
The single-module engine controller controlled ignition timing, air/fuel ratio, emissions control devices and idle speed. The controller updated and revised its programming to meet all operating conditions through an adaptive memory. It also evaluated input regarding fuel flow or ignition timing (or both).
The throttle body system used a single fuel injector in the throttle body assembly. The duration and timing of the fuel injection pulses on the engine were regulated by the computer.
The multple-point injection used four fuel injectors - one for each port of the intake manifold on the Turbo 1 engine. Fuel was injected alternately through the four injectors in pulses regulated by the single-module engine controller. The pulses and engine spark timing were coordinated for maximum engine efficiency in all operating conditions starting, idling, accelerating, cruising, decelerating, etc. The system also used a dual-tuned intake, with individual runners leading to each cylinder from the manifold plenum chamber. Air was fed into the plenum from the throttle body so that horsepower and torque efficiency were superior to a non-tuned design.
(Note: A similar, dual-tuned intake design was also used on the Mitsubishi 3.0-liter multi-point engine).
Nearly all Chrysler engines were fuel injected in 1988. The sole holdout was the Gran Fury/Diplomat/Fifth Avenue's 318, which would remain carbureted until its last days in 1989, when the last car of the pre-Iaccoca Chrysler Corporation would disappear in favor of the new front wheel driven line. The 318 was, however, fuel injected for the first time in 1988 - in trucks - using two injectors, each located in the throttle body (one for each bore). For the moment, the only Chrysler engines with multiple-point injection were the turbocharged fours; the 3.3 liter V6 would shortly join them. (Mexican 2.5 liter engines also had multiple point injection to deal with the heights of Mexico City.)
Turbochargers
The turbocharger provided extra acceleration on demand. A small, stainless steel turbine wheel, in a housing which was bolted to the exhaust manifold, was driven at tremendously high speeds by hot exhaust gases and it rotated a small aluminum compressor on the other end of the same drive shaft. The compressor was located ahead of the intake manifold where it rammed air-fuel mixtures into the combustion chambers under pressure to produce greater power in each cylinder when the spark plug fires. Use of a turbocharger water passage, pioneered by Chrysler Corporation, helped reduce the turbine bearing and oil passage temperature during the critical period following engine shut off.
For 1988, the turbocharger on the Turbo I engine was smaller and had less rotating inertia to overcome, thus achieving faster throttle response.
The computer continuously monitored eight parameters in order to maintain the proper boost level and fuel-air ratio under all engine operating conditions.
If the boost pressure were not limited, the engine would be subjected to higher pressures and higher temperatures than the engine could tolerate. The maximum boost level was physically controlled by a wastegate (a valve that permits some of the exhaust gases to bypass the turbine wheel). This regulated the turbine and in turn the air compressor, thus preventing unwanted air flow into the engine. Controlled transient overboost was permitted during snap acceleration for up to 10 seconds. (People like Gus Mahon obtained surprisingly good acceleration for racing by increasing the maximum boost level and overboost times.)
The wastegate actuator solenoid was located in the pressure signal line leading from the turbocharger to the wastegate actuator. This solenoid receives a signal from the computer and, in turn, controlled the position of the wastegate through the actuator.
A new wastegate power source was used for 1988-pressurized air from the turbocharger instead of manifold vacuum. This allows for a leaner fuel mixture and increased spark advance which enhances fuel economy.
Control of spark knock was achieved by regulating boost as well as spark. When the computer sensed spark knock in a cylinder, it signalled a small spark retard to that cylinder only. If the knock persisted, it then lowered engine boost until the spark knock stops. Performance loss was therefore minimized.
The turbocharger bearings on the shaft between the turbine and compressor were cooled and lubricated by oil that was pumped through and around the bearings. A water jacket around the turbine and compressor bearings cooled the oil and helped to increase the life of the oil and the turbocharger. And, naturally, the air that flowed through the engine compartment helped in the job of cooling.
The Turbo I engine had a horsepower rating of 146 @ 5,200 rpm-that's a 57% increase over the rating of 93 horsepower @ 4,800 rpm for an electronic fuel-injected 2.2-liter engine without the turbocharger. Engine torque was increased to 170 pounds-feet @ 2,400 rpm with the turbo-charger-a 39% increase over the 122 pounds-feet @ 3,200 rpm for the same engine without the turbocharger.
The Turbo I had an automatic shut down relay to deactivate the fuel pump on any impact that was sufficient to stop the engine. Premium unleaded fuel was recommended.
Electrical
All cars had electronic ignition, which Chrysler had brought to the world in 1971. The distributor used on all domestic engines had an electromagnet-rather than a permanent magnet-that created the magnetic field. And it used rotor vanes-rather than a reluctor-to rotate through the magnetic field. These vanes change the voltage level in the magnetic field-and that change triggered the electronic system to amplify the current to the ignition coil for firing the spark plugs.
The Mitsubishi-built 3.0-liter MPIV-6 had an optical distributor in which the breaking of a light beam by a camshaft-driven shutter was used to control fuel injection, ignition timing and idle speeds. Firing impulses from the coil to each individual cylinder were delivered in the conventional manner.
A 90 amp alternator was used on all engines; it had variable output capacity and no visible voltage regulator. Output was controlled according to electrical system demand by the computer to regulate charging. Expanded memory codes within the same module help mechanics make quicker and more accurate checks of the charging system. (Gran Fury/Diplomats/Fifth Avenue had a separate electronic voltage regulator that had no moving parts. Diodes, transistors and advanced circuitry maintain the correct voltage in the electrical system.
Batteries were maintenance-free; headlights were halogen; and spark plugs used long noses and copper cores (except in Mitsu four-cylinders) to resist plug fouling.
A variety of stereos were available, some with CD players, and some with the Infinity speaker system that relied more on individual amplifiers glued to each speaker than on power of the head unit itself. This system, apparently designed to frustrate owners of older cars, provided excellent sound and strong bass if not the kind of longevity and ease of replacement owners of two-decade-old cars would appreciate. Top end models had a five-segment equalizer which helped in fine tuning, easy to use rocker switches for common functions that were less easy than knobs, and a joystick for speaker control which could be hard to adjust and easily thrown off if you happened to go over a bump while adjusting it; that said, if you were trying to troubleshoot, there's nothing like being able to immediately direct all sound to a particular speaker.
New for 1988 was an "electronic traffic cop," which connected the engine controller, body computer, overhead console display, trip computer, and engine compartment sensor modules on a data network, replacing individual wires (this idea would become a body-wide electric "bus" for the 1999 Grand Cherokee). This chip allowed the car's microprocessors to share information and it assigned priorities to messages seeking access to the network, replacing five standalone timing and logic control modules.
Engines
2.2 / 2.5 liter four-cylinders
The 2.2 liter four-cylinder engines had a fast-burn cylinder head. Swirl-induced turbulence in the combustion chamber increased the rate of combustion which made engine operation smooth and consistent. The head was designed to work with electronic fuel injection and provide reduced knocking, smoother idle and improved overall driveability.
Other engine features included a cast aluminum alloy cylinder head, post-hardened nodular iron camshaft (an industry first), needle bearing roller camshaft followers, five camshaft bearings, colbalt-iron alloy exhaust valve seat inserts, cast aluminum alloy intake manifold and cast iron
exhaust manifold, molybdenum-filled nodular iron top
piston rings, cast iron block, ceramic
water pump shaft seal seat, chrome-plated
intake and exhaust valve stems with steel-backed rubber valve stem seals, dual chrome-vanadium valve springs, cast aluminum pistons with steel struts, and cog-belt-driven overhead cam. Horsepower was 93 @ 4,800 rpm; torque was 122 lb ft @ 3,200 rpm (without turbo).
The 2.5 liter version was a stroked 2.2, standard on minivans (except Grand LE) and optional on Sundance/Shadow, Reliant/Aries, and Caravelle/600. In 1988, it produced 96 horsepower @ 4,400 rpm and 133 lb ft of torque @ 2,800 rpm (it would move up to 100 hp and 135 lb-ft.)
The 2.2 liter had two turbocharged versions, with and without intercooler; the intercooler proved to be good for about 25 horsepower.
New roller camshaft followers appeared in 1988 to increase idle quality and gas mileage and idle and low speeds; they also reduced noise. The rocker arms which transmit motion from the camshaft to the valves had neede bearing rollers at the points of contact with the camshaft to reduce friction.
Improved idle quality was achieved because the intake and exhaust valves were open simultaneously for a shorter period for each engine revolution. The less time the valves were open simultaneously, the less exhaust mixes with the incoming fuel and air-and this evened the idle.
Roller rocker camshafts were adopted in all 2.2 and 2.5 engines, improving idle quality, gas mileage, and longevity by cutting friction between the cam and hardened inserts on their followers; post-hardening of the nodular iron camshaft was believed to be an industry first. The new system cut friction by 20%, raising city gas mileage by 4% (automatics) or 3% (manuals). A single engine computer (with two boards) replaced the dual setup.
Other noise reduction steps included changes to the camshaft belt drive and sprockets, camshaft followers, accessory crankshaft pulley, power steering, and fuel pump.
Mitsubishi 3.0 V6 and four-cylinder engines
A 3-liter Mitsubishi V6 was also used pending the introduction of the 3.3 V6 (which was still used today - as was a 2.5 liter version of the Mitsubishi).
Though it generated no more power than the 2.2 turbo - in fact, it generated less power - its horsepower almost equalled the 318 V8 (the V6's torque was far lower!) and its broader torque curve made it more comfortable in the minivans than the 2.5 turbo that was to appear in 1989.
There were also four Mitsubishi four-cylinder engines used (all in the Colts): a 1.5 liter 2-barrel (standard on most Colts), 1.5 MPI (Colt DL), 1.6 liter turbo (Colt DL or Premier with Turbo package), and 2.0 liter MPI (Vista Wagon).
The 2.0 engine, with its long stroke, used two counterbalancing shafts in the engine to damp vibrations, a trick picked up by Chrysler in its 2.5.
The Mopar cars of 1988 (summary)
By 1988, most of the Chrysler, Plymouth, and Dodge cars could be described in two letters: K and L. Most cars (including the minivans) were based off the extended K-car platforms (hence the pet name EEK); the L-body Omni/Horizon still soldiered on, without the Turismo, O24, Rampage, and other variants, but it was soon to disappear without replacement (at least not as of 2006). The Reliant and Aries themselves were finally gone, and the M-body Gran Fury/Diplomat/Fifth Avenue stayed in production to service America's police and taxi fleets; the Colts continued, as they would until Chrysler's early-1990s rebirth. Under the placid waters of endless variations on the K platform (including a new, longer-wheelbase setup introduced in 1988), engineers worked on specialty variants, to appear with the Shelby or R/T tags. Not until the Viper would the corporation gain an entirely new vehicle; but the process that brought about the Viper would soon replace just about every vehicle Chrysler Corporation made, instigating a renaissance before the nightmare years and, hopefully, another renaissance.
The Chrysler TC by Maserati also finally arrived, built in Italy and shipped to selected dealers in small - smaller than desired - quantities. Intended to appear before the LeBaron GTS, which would be styled like the more expensive, exclusive TC, the TC showed up afterwards, making it look like a copy of a Chrysler, not the hoped-for effect.
Some standard features for 1988 included clearcoat paint, power brakes, dual hydraulic brakes, front wheel disc brakes (ventilated on most models), semi-metallic pads on front drive models, self-adjusting rear drum brakes, and electronic ignition. Chrysler also had a 7 year - 70,000 mile powertrain warranty.
Extensive anticorrosion treatments protected all North American-built cars. Even before the metal was formed into body panels, it was coated to protect against corrosion. Galvanized steel was used extensively for many body panels. And still other panels were coated with zinc-rich primer, which retains its integrity even after forming or stamping.
When assembled, each car body was thoroughly cleaned and coated with special chemicals in a 7-step dip-and-spray process for additional protection against all forms of corrosion (see later in this page).
WHEELBASE | ORIGIN | SERIES | BODY STYLES |
97.0" | EEK (P) | Sundance/Shadow | 2-door liftback 4-door liftback |
112.0" | EEK (S) | Voyager/Caravan | 3-door wagon with liftgate |
119.0" | EEK (S) | Grand Voyager/Grand Caravan | 3-door wagon with liftgate |
99.1" | L | Horizon/Omni | 5-door hatchback |
100.3" | K | Reliant/Aries/LeBaron | 2-door sedan, 4-door sedan, 2 door conv. (LeBaron) |
100.4" | K | Reliant/Aries | 4-door wagon |
103.3" | EEK (E) | Caravelle/600/New Yorker Turbo | 4-door sedan |
112.6" | M | Gran Fury/Diplomat/Fifth Ave | 4-door sedan |
93.7" | MMC | Colt | 3-door hatchback, 4-door sedan, 5-door wagon |
103.3" | MMC | Colt Vista 2WD | 5-door wagon |
103.5" | MMC | Colt Vista 4WD | 5-door wagon |
97.0 | EEK (G) | Daytona | 2-door liftback |
104.3 | EEK (C) | New Yorker (not Turbo) / Dynasty | 4-door sedan |
103.1 | EEK (H) | LeBaron GTS / Lancer | 4-door hatchback |
95.9 | MMC | Conquest | 2-door hatch |
Fuel injection
The single-module engine controller controlled ignition timing, air/fuel ratio, emissions control devices and idle speed. The controller updated and revised its programming to meet all operating conditions through an adaptive memory. It also evaluated input regarding fuel flow or ignition timing (or both).
The throttle body system used a single fuel injector in the throttle body assembly. The duration and timing of the fuel injection pulses on the engine were regulated by the computer.
(Note: A similar, dual-tuned intake design was also used on the Mitsubishi 3.0-liter multi-point engine).
Nearly all Chrysler engines were fuel injected in 1988. The sole holdout was the Gran Fury/Diplomat/Fifth Avenue's 318, which would remain carbureted until its last days in 1989, when the last car of the pre-Iaccoca Chrysler Corporation would disappear in favor of the new front wheel driven line. The 318 was, however, fuel injected for the first time in 1988 - in trucks - using two injectors, each located in the throttle body (one for each bore). For the moment, the only Chrysler engines with multiple-point injection were the turbocharged fours; the 3.3 liter V6 would shortly join them. (Mexican 2.5 liter engines also had multiple point injection to deal with the heights of Mexico City.)
Turbochargers
The turbocharger provided extra acceleration on demand. A small, stainless steel turbine wheel, in a housing which was bolted to the exhaust manifold, was driven at tremendously high speeds by hot exhaust gases and it rotated a small aluminum compressor on the other end of the same drive shaft. The compressor was located ahead of the intake manifold where it rammed air-fuel mixtures into the combustion chambers under pressure to produce greater power in each cylinder when the spark plug fires. Use of a turbocharger water passage, pioneered by Chrysler Corporation, helped reduce the turbine bearing and oil passage temperature during the critical period following engine shut off.
For 1988, the turbocharger on the Turbo I engine was smaller and had less rotating inertia to overcome, thus achieving faster throttle response.
The computer continuously monitored eight parameters in order to maintain the proper boost level and fuel-air ratio under all engine operating conditions.
The wastegate actuator solenoid was located in the pressure signal line leading from the turbocharger to the wastegate actuator. This solenoid receives a signal from the computer and, in turn, controlled the position of the wastegate through the actuator.
A new wastegate power source was used for 1988-pressurized air from the turbocharger instead of manifold vacuum. This allows for a leaner fuel mixture and increased spark advance which enhances fuel economy.
Control of spark knock was achieved by regulating boost as well as spark. When the computer sensed spark knock in a cylinder, it signalled a small spark retard to that cylinder only. If the knock persisted, it then lowered engine boost until the spark knock stops. Performance loss was therefore minimized.
The turbocharger bearings on the shaft between the turbine and compressor were cooled and lubricated by oil that was pumped through and around the bearings. A water jacket around the turbine and compressor bearings cooled the oil and helped to increase the life of the oil and the turbocharger. And, naturally, the air that flowed through the engine compartment helped in the job of cooling.
The Turbo I engine had a horsepower rating of 146 @ 5,200 rpm-that's a 57% increase over the rating of 93 horsepower @ 4,800 rpm for an electronic fuel-injected 2.2-liter engine without the turbocharger. Engine torque was increased to 170 pounds-feet @ 2,400 rpm with the turbo-charger-a 39% increase over the 122 pounds-feet @ 3,200 rpm for the same engine without the turbocharger.
The Turbo I had an automatic shut down relay to deactivate the fuel pump on any impact that was sufficient to stop the engine. Premium unleaded fuel was recommended.
Electrical
All cars had electronic ignition, which Chrysler had brought to the world in 1971. The distributor used on all domestic engines had an electromagnet-rather than a permanent magnet-that created the magnetic field. And it used rotor vanes-rather than a reluctor-to rotate through the magnetic field. These vanes change the voltage level in the magnetic field-and that change triggered the electronic system to amplify the current to the ignition coil for firing the spark plugs.
The Mitsubishi-built 3.0-liter MPIV-6 had an optical distributor in which the breaking of a light beam by a camshaft-driven shutter was used to control fuel injection, ignition timing and idle speeds. Firing impulses from the coil to each individual cylinder were delivered in the conventional manner.
Batteries were maintenance-free; headlights were halogen; and spark plugs used long noses and copper cores (except in Mitsu four-cylinders) to resist plug fouling.
A variety of stereos were available, some with CD players, and some with the Infinity speaker system that relied more on individual amplifiers glued to each speaker than on power of the head unit itself. This system, apparently designed to frustrate owners of older cars, provided excellent sound and strong bass if not the kind of longevity and ease of replacement owners of two-decade-old cars would appreciate. Top end models had a five-segment equalizer which helped in fine tuning, easy to use rocker switches for common functions that were less easy than knobs, and a joystick for speaker control which could be hard to adjust and easily thrown off if you happened to go over a bump while adjusting it; that said, if you were trying to troubleshoot, there's nothing like being able to immediately direct all sound to a particular speaker.
New for 1988 was an "electronic traffic cop," which connected the engine controller, body computer, overhead console display, trip computer, and engine compartment sensor modules on a data network, replacing individual wires (this idea would become a body-wide electric "bus" for the 1999 Grand Cherokee). This chip allowed the car's microprocessors to share information and it assigned priorities to messages seeking access to the network, replacing five standalone timing and logic control modules.
Engines
2.2 / 2.5 liter four-cylinders
Other engine features included a cast aluminum alloy cylinder head, post-hardened nodular iron camshaft (an industry first), needle bearing roller camshaft followers, five camshaft bearings, colbalt-iron alloy exhaust valve seat inserts, cast aluminum alloy intake manifold and cast iron
exhaust manifold, molybdenum-filled nodular iron top
piston rings, cast iron block, ceramic
water pump shaft seal seat, chrome-plated
intake and exhaust valve stems with steel-backed rubber valve stem seals, dual chrome-vanadium valve springs, cast aluminum pistons with steel struts, and cog-belt-driven overhead cam. Horsepower was 93 @ 4,800 rpm; torque was 122 lb ft @ 3,200 rpm (without turbo).
The 2.2 liter had two turbocharged versions, with and without intercooler; the intercooler proved to be good for about 25 horsepower.
New roller camshaft followers appeared in 1988 to increase idle quality and gas mileage and idle and low speeds; they also reduced noise. The rocker arms which transmit motion from the camshaft to the valves had neede bearing rollers at the points of contact with the camshaft to reduce friction.
Improved idle quality was achieved because the intake and exhaust valves were open simultaneously for a shorter period for each engine revolution. The less time the valves were open simultaneously, the less exhaust mixes with the incoming fuel and air-and this evened the idle.
Roller rocker camshafts were adopted in all 2.2 and 2.5 engines, improving idle quality, gas mileage, and longevity by cutting friction between the cam and hardened inserts on their followers; post-hardening of the nodular iron camshaft was believed to be an industry first. The new system cut friction by 20%, raising city gas mileage by 4% (automatics) or 3% (manuals). A single engine computer (with two boards) replaced the dual setup.
Other noise reduction steps included changes to the camshaft belt drive and sprockets, camshaft followers, accessory crankshaft pulley, power steering, and fuel pump.
Mitsubishi 3.0 V6 and four-cylinder engines
Though it generated no more power than the 2.2 turbo - in fact, it generated less power - its horsepower almost equalled the 318 V8 (the V6's torque was far lower!) and its broader torque curve made it more comfortable in the minivans than the 2.5 turbo that was to appear in 1989.
There were also four Mitsubishi four-cylinder engines used (all in the Colts): a 1.5 liter 2-barrel (standard on most Colts), 1.5 MPI (Colt DL), 1.6 liter turbo (Colt DL or Premier with Turbo package), and 2.0 liter MPI (Vista Wagon).
The 2.0 engine, with its long stroke, used two counterbalancing shafts in the engine to damp vibrations, a trick picked up by Chrysler in its 2.5.
Mitsubishi Engine | Type | Compression | Horsepower | lb-ft |
---|---|---|---|---|
1.5 (91.5 CID) 2-bbl | I-4 | 9.4 | [email protected] | [email protected] |
1.5 MPI | I-4 | 9.4 | [email protected] | [email protected] |
1.6 (97 CID) Turbo | I-4 T | 7.6 | [email protected] | [email protected] |
2.0 (122 CID) MR | I-4 | 8.8 | [email protected] | [email protected] |
2.6 Turbo (Conquest) | I-4 | 7:1 | 188 @ 5,000 | 234 @ 2,500 |
3.0 (181) V-6 | V-6 | 8.9 | [email protected] | [email protected] |
Chrysler Engine | Type | Compression | Horsepower | lb-ft |
2.2 (135 CID) EFI | I-4 | 9.5 | [email protected] | [email protected] |
2.2 (135 CID) Turbo I | I-4 T | 8.0 | [email protected] | [email protected] |
2.2 Turbo II | I-4 T | 8.1:1 | [email protected],200 | [email protected],200 |
2.5 (153 CID) EFI | I-4 | 8.9 | [email protected] | [email protected] |
5.2 (318) 2-bbl V-8 | V-8 | 9.1 | [email protected] P/D [email protected] Chr. | [email protected] P/D [email protected] Chr |
The effect of turbocharging is apparent from these figures for both companies. Also interesting is the bias toward torque from both - rather different from contemporary Honda's high horsepower and low torque ratings. EPA estimates of gas mileage (generally optimistic): |