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).
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.)
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.
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.
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.
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 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):
Colt DL Hatchback
Colt Premier Sedan
Trucks used the 5.2 liter (318 cid) V8 engine, as well as a 3.9 liter V6 derived from the 318; these were fuel injected using twin low-pressure injectors, one for each bore in the throttle body.
The manual transaxle was synchronized in all forward gears for smooth, quiet shifting, with an overdrive (0.72 to 1) fifth gear for highway fuel economy. First, second, third and fourth gear ratios were designed for quick acceleration. TorqueFlite was a 3-speed automatic with torque converter and a wide ratio between second and high for efficiency.
The Chrysler 5-speed manual transaxle’s second, third and fourth gear ratios provide for quick acceleration response and feel:
Second ................................................ 2.08
Fifth .................................................. 0.72
Second ................................................ 2.08
Fifth .................................................. 0.72
The overdrive ratio was 0.72 for all models, including Voyager, to stretch highway fuel economy. This overdrive ratio also reduced engine rpm and resulted in quieter engine operation. Isolators for the selector and crossover cables-plus reduced clearances between shift components-were designed to further enhance quiet, smooth operation. (Mitsubishi models got a Mitsu 4 or 5 speed manual.)
Galvanized and galvannealed steel, zincrometal, fiberglass, lower body urethane protective coating, plastics and special paints and primers were used extensively on all North American-built models for protection against corrosion.
Brake linings were durable semi-metallic. A power booster was standard on all models. All models (except Horizon/Omni) used ventilated discs for better heat dissipation. Rear drum brakes were self-adjusting on all U.S.-built cars.
All models had fuel system features that provided protection against leakage during side, rear and angular front impacts, including sturdy fuel tank construction, fuel tank retention with longitudinal and lateral reinforcements, a special valve on the top of the fuel tank to prevent leakage during rollover, reinforcements to body structural members and, on all models except the rear-wheel drive Gran Fury, the fuel tank was located forward of the rear suspension and between the body rails for extra protection.
A stainless steel exhaust system was standard on all domestic models. All pipes, hangers, the catalytic converter housing, and the muffler were made of a corrosion resistant stainless steel alloy developed specifically for exhaust systems.
The catalytic converter had a stainless steel shell that housed ceramic honeycomb monolithic elements that were coated with noble metal catalytic agents. The monolithic element was separated from the shell by a stainless steel mesh, which helped to protect the honeycomb element by providing a spring-type shock-absorbing mounting. The noble metal catalyst in the converter caused a heat-releasing reaction to occur in the exhaust gases that oxidized and reduced emissions to meet clean air standards. Unleaded gasoline must be used with all catalytic converter systems as leaded gasoline would coat the catalyst, rendering it ineffective.
EFI engines had a smaller catalyst than former carbureted engines. Air was injected by an aspirator (instead of an air pump) which reduced engine load and improved fuel economy. The turbo and V6 require no air pump or aspirator for air injection, because injectors were located at the intake port of each cylinder. Fuel control was even more precise than in the single-point EFI engines.
[Only the Plymouth names are used for convenience; details on Diplomat, Gran Fury, and Fifth Avenue are on the M-body page.]
Body quietness was aided with computers; Chrysler pioneered this technique even if cost issues tended to obscure their approach.
Exterior ornamentation and moldings were isolated from body metal to prevent electrolytic action and corrosion between dissimilar metals. Lower body protection on cars was provided with special stone-chip resistant urethane coating. Chrome plating of bright trim and fasteners were improved for 1988. Door hinges were bolted onto the body and were galvanized or zinc-plated on selected models. The door was covered with zinc-rich paint. Transparent tape on windshields, back windows and liftgate moldings help prevent paint film breakthrough-particularly at the corners. Underbody and underhood components received a variety of primers and other treatments to prevent corrosion.
Box-section construction was used for windshield pillars, roof side rails, bodyside sills, door opening frames and lower body structural members where extra strength was required.
Inner and outer roof panels were bonded and welded together for double panel strength. Roof bows, roof side rails and headers were formed of box-sections when inner and outer steel panels were welded together.
A new designed roll-down window mechanism was used for the rear doors in Reliant and Sundance 4-door models. The mechanism was a rack-and-pinion gear set made of tough injection-molded Delrin plastic. The Delrin rack gear was flexible and slides along a T-shaped steel track to move the glass up or down as the window crank turns the pinion gear. The window glass was fastened to the sliding rack gear by a link. Total up-and-down window travel was ten inches. This assembly weighed 60% less than a traditional window mechanism. A small fixed window was used in the door behind the sliding glass with this mechanism.
LeBaron Convertible gained hydraulically-dampened engine mounts to reduce low-frequency shake. Reliant, Sundance, Caravelle, and Gran Fury Salon had a counterbalanced hood (no prop). Dynasty and New Yorker got new front struts to reduce ride harshness and noise; partly grooved cylinders allowed hydraulic fluid to bypass the strut piston in normal driving, but under poor conditions the strut piston slid past the end of the grooves, increasing resistance and reducing the impact of the suspension against its internal stops. This was a domestic industry first. The Dynasty and New Yorker also had an optional power trunk lid pull-down mechanism.
Four models now had electrically driven speedometer and odometer (replacing cable drive) - New Yorker/Dynasty and LeBaron GTS/Lancer.
Painting was a seven-step process:
Sundance, Reliant, Daytona, Caravelle, Dynasty, Shadow, 600, and Aries had a rear suspension system made up of a transverse beam with torsion-tube anti-roll control, trailing arms, coil springs, shock absorbers, located laterally by a track bar. All components were rubber-isolated from the car body. The Horizon rear suspension system was of semi-independent design in which coil springs surrounded the shock absorbers, and there were trailing arms, but no track bar. The V8 cars and Voyager had 4-leaf spring rear suspension.
On North American-built models, front suspension was of an independent coil spring-and-strut design with an integral, linkless antisway bar. These components were completely rubber-isolated from the car body. The result was a controlled, cushioned and comfortable ride. Dual-path upper iso-Strut mountings further isolated noise and vibration on all K/EEK based front-drive cars.
Shock-absorbing struts mounted within low-rate
coil springs and a linkless front antisway bar combine to
provide a comfortable, controlled ride. Compliant
rubber bushings isolate suspension components from the
car body to further cushion vibrations and damp sounds.
A small negative scrub radius was designed into the suspension steering geometry to aid directional stability and straight-line braking. This geometry helped to reduce steering loads in the event of a tire failure, uneven braking or when one or more wheels run on low traction road surfaces while the other wheels were on solid pavement.
Front-wheel struts (shock absorbers) were connected directly to the steering knuckles and to the car structure - so upper control arms were not required with this suspension. Lower control arms were connected to the steering knuckles through semi-permanently lubricated ball joints.
The upper mounts for the iso-Strut front suspension as used on K-derived (EEK) front-drivers had dual paths for isolating noise and vibration-one path receives and damps shock absorber loads, the other path receives and damps spring loads. The dual-path design was thus more effective in isolating shock absorber and spring generated disturbances from the vehicle.
The front suspension was fully independent, with a one-piece strut assembly tower in the body, jounce bumpers, and isolator rubber bushings. Gas-pressurized shocks were standard.
A linkless antisway bar (see drawing above), attached directly to the car's front structural crossmember and to the front-wheel lower control arms, provided more resistance to car roll and sway than the previous link-type antisway bar - and it permitted use of lower rate front coil springs for a softer, more comfortable ride. Previously, the antisway bar was attached to the crossmember by links which deflected under stress and reduced roll stability, which was compensated for by stiffer coil springs. In addition, front suspension and steering geometry were changed to give the driver improved and more easily controlled steering responses in all driving situations. The linkless antisway bar was standard on all 1988 front drive U.S.-built cars.
Both L and EEK used trailing-arm rear suspensions, though in different forms. Omni/Horizon used was a semi-independent type with tubular shock absorbers mounted within the coil springs. EEKs used shock absorbers mounted adjacent to the low-rate coil springs. This suspension utilizes a beam axle (inverted U-section) which carries the wheel spindles at each end. Two trailing arms connect the axle and suspension assembly to the car structure. A torsion tube housed inside the U-section axle provides anti-roll control. Lateral suspension movement was controlled by a track bar attached at pivot points on the beam axle and a body-mounted bracket.
Minivans had a dual-path iso-Strut front suspension and a multi-leaf (4 leaves per spring) rear suspension; the rear leaf suspension provided the best stability and cargo capacity. A heavy duty version was optional.
Power from the engine flowed through the transaxle (transmission, transfer gear and axle differential gears). The differential gears divided the power between the left and right drive shafts, which were splined to the front wheel hubs. The front wheels were bolted to the hubs.
The Sundance/Shadow with turbocharged engine used an equal length drive shaft system. It features short, solid drive interconnecting half shafts of equal length on the left and right side. The unequal length system used on all other front drive models had a short, solid drive interconnecting shaft on the left side with a longer tubular drive shaft on the right.
The equal length system minimizes torque steer. During hard acceleration the car will not veer from a straight line.
This steering was engineered for low turning effort, good returnability and excellent stability. A negative scrub radius, designed into the steering geometry, improves directional stability and straight-line braking by making the steering less susceptible to forces transmitted by road irregularities and braking action.
All front-drivers used rack and pinion steering; the rear-drivers used recirculating-ball steering. A "cold-prime" power steering pump provides power assist for steering at lower engine rpm when starting the car in cold weather.
Caravelle had an available precision-feel rack-and-pinion power-assisted steering with a quick ratio of 14 to 1 in place of the standard 18 to 1 ratio. It includes a high-flow rate power steering pump. This combination provides quick steering response and precise steering control. The quick ratio steering was included with the optional Sport Handling Suspension on Caravelle models, and was standard on Sundance/Shadow with the 14:1 ratio.
A pump speed reduction of 1,050 rpm was been achieved while maintaining the same initial power steering response in cold start-ups; and a smaller displacement pump was used with all front drive models. This smaller pump used 25% less engine power than previous pumps, effecting a significant improvement in fuel economy without any loss in power assist for steering.
Sundance 50/50 seats and bucket seats had been redesigned for more convenient operation and reduced travel. Operating the recliner mechanism takes less effort and the handle was sturdier and easier to grasp than in 1987 models. Lever travel was reduced by 60%. The seat side shields had also been redesigned to provide more hand clearance to the operating lever.
A new, larger fan and scroll on Sundance deliver more air flow for faster cooling and ventilation. Ventilation and air flow to the rear compartment were improved whenever the heater and air conditioner were in the vent or bi-level modes. The fan speed was tailored to the Sundance interior
to balance air flow and sound level.
Switches that were computer-designed to be easy and comfortable to operate-that s the kind of extra touch you get from Chrysler engineering. The low-travel switches that control the optional power windows and door locks on Caravelle and the power door locks on Reliant LE, Voyager and Sundance had rockers with a raised area at one end and a depression at the other end. By means of these surface variations, the driver or passenger can operate the switches by sense of touch. There was no need to actually look at the switches. You push the raised portion of the switch to raise windows and lock doors, the depressed portion to lower windows and unlock doors.
Chrysler introduced a larger New Yorker, including a Landau model, while confusingly retaining its E-car version as the New Yorker Turbo; the difference in wheelbase was a single inch, but the larger model was Mitsubishi-V6 powered rather than turbo-powered. The New Yorkers had four wheel power disc anti-lock brakes, automatic load levelling, electronic controls mediated by a body computer, an Infinity stereo, CD player (when they were still unusual), and new exterior paint process. The longer-wheelbase New Yorker Sedan and Landau were also sold, with lesser trim, as the Dodge Dynasty.
Chrysler Heritage • History by Year • Chrysler People and Bios • Corporate Facts and History
Creating the Horizon
Chrysler 300 J, K, L
All Mopar Car and Truck News
Chrysler 300 Letter Cars
The Engine Cleanup Committee