The Forgotten DSM
Lotus Elise, Formerly K- series motor till 1999420a is closest related to the 111s tuning. The 111s output was 143hp, has revised intake, direct electronic ignition, and sequential fuel injection.
K series 1.8 , note the intake plenum, throttle body and water crossover pipe.
In 1999, Lotus introduced the 111s version of the Elise. It provided 143 bhp at 7.000 rpm and 128 ft-lb (174 Nm) with the new variable valve control (VVC) version of the K engine. There were larger inlet and exhaust valves, a new aluminium inlet manifold, and a revised plenum chamber. The Bosch multi-point fuel injection had adaptive control and distributorless ignition used individual coils for each cylinder. The first version of this motor was introduced in 1995 with hydrolic tappets ( lashers) , the same time as the 420a was introduced to Diamond Star Motors goup
Eagle Talon ESR
This is an underdog that that performs well out of the box. The turbocharged 420a motor powering this Eagle Talon ESR is a breed between Chrysler / Dodge, Neon and Lotus Elise 90-95 K series DOHC motor. In 1996 the Lotus Elise K series motor would no longer pass emissions under european standards as it did not have variable valve timing standard to produce horsepower levels with lower emissions. Lotus allowed Chrysler to use the head design with some modifications to be used while mated to a iron Dodge Neon block for year models 95-99 as the non- turbo trim. The pistons are 10 percent silicon aluminum Mahl pistons with a knife edge crankshaft. The Oem output is 143bhp and bore is still 87.5mm as designed by Lotus. With the same amount of boost as the Eagle Talon TSI or Mitsubishi Eclipse GST , the ESR can produce a maximum 287 bhp. This is 77hp more than either of the other turbocharged cousins of this second generation DSM style body. This Eagle Talon ESR has been decorated with 7 pieces of powdercoated Kandy Red.
Turbocharging to ESI started with Hahn racecraft. It was driven daily by Lori Hahn of which I have spoken to myself . They found that the completely stock motor was very tough and wanted to educate the world. Ten years pass by and they still sell the 420a Turbo kit with the OEM 16G turbo w/ internal wastegate. For ten years Hahn Racecraft boosted a 420a up to 270hp + before replacing the pistons and rods with forged versions. From there Hahn managed to have the 420a basically stock in every way produce more than 400whp for hundreds of runs. The car was finally retired and used as a daily driver for one of Bill Hahn's grand children. He promptly wrecked it.
ESR designation comes from turbocharging the ESi originally non-turbo motor. The "i" designation is for inline 4 cylinder models. The originally turbocharged 4g63 motor in the TSI simply put a "T" in from of the "si" to replace the "e". The "esi" stood for economy sport inline. The "TSI" is turbo sport inline. I believe the turbo 420a is still ecenomical and should not steal the TSI tag. This is where keeping the "e" and add an "R" comes into play as it is the 420a ESI motor tuned for Racing. This preserves the 4g63 owners designation and sets tuned stock 420a motors aside from untuned ESi motors.
My ESR 420a
Est horsepower : 271
Nominal Boost- 9.25 psi
Tial 38mm Wastegate, 7.25psi spring
Turbonetics Turbo manifold
Turbonetics T3/T4 60-1
HKS 1 g style blow off valve
Treadstone oil feed line/ drain kit.
Walbro 255 HP fuel pump
Fuel Cut Defender
270cc Accel injectors
Bell Engineering Adjustable FMU
Chrysler 420A Information
A low profile, cast aluminum cross-flow cylinder head has pent-roof combustion chambers housing four valves per cylinder. Dual camshafts run in six bearings with removable caps that are machined in head base material. Powdered metal valve seat inserts and valve guides are pressed into the head. Spark plugs thread into the center of the combustion chamber through wells cast into the head.The ports are a rectangle with a half cirlcle on each side of the rectangle.The rectangle is .95" wide and 1.25" tall. The diameter of the two half-circles therefore is 1.25" as well. I suck at math, so don't expect much Area of the rectangle: 1.188 inches squared Area of the circle: 1.227 inches squared The total cross-sectional area of the intake port is 2.415 inches squared. This does not include the space allowed for the fuel injectors.To provide turbulence in the cylinders that contributes to the rapid combustion necessary for low emissions and efficient operation on regular-grade gasoline, the intake ports cause the incoming air to "tumble" from top to bottom of the cylinders. The degree of tumbling action was balanced against the conflicting need for high air flow to obtain high power output.
Bore: 3.444
Stroke: 3.268
Rod Lgth: 5.470
C/H: 1.236 Head
CC: 52
Comp Ratio: 9.6:1
Dish/Dome Vol.: +5.0
Intake and exhaust manifolds
A two-piece cast aluminum intake manifold features 18.5 in. (470 mm) primary runners to enhance low-speed torque. The runners are curved to provide as much length as possible in the compact engine compartment of the Avenger and Sebring. A tapered plenum and elbow section deliver air from the throttle body to the runners. Recirculated exhaust gas (EGR) for NOx emission control enters the manifold at the base of the throttle body.
A compact, light weight nodular cast iron exhaust allows exhaust gas to heat catalytic converter to operating temperature quickly for low emissions.
Valve Train
Four valves per cylinder are actuated by dual overhead camshafts. Valve seat outer diameters are 1.36 in. (34.5 mm), intake, and 1.16 in. (29.5 mm), exhaust. All valves have 0.25 in. (6 mm) chrome plated stems. Intake valve lift is 0.31 in. (7.8 mm) and exhaust valve lift is 0.28 in. (7.0 mm). Valves have a 48 degree included angle; exhaust valves forward, intakes rearward. Each valve is operated by an end- pivot rocker arm. Each 0.79 in. (20 mm) roller cam follower runs on roller-bearings. Each rocker pivots on an inboard-mounted, fixed hydraulic lash adjuster. Barrel-shaped single valve springs provide control of valve actuation to 7200 rpm.
The nodular iron camshaft is hardened after machining to provide the requisite durability characteristics for roller followers. A state-of- the-art cog belt drives the camshaft. The belt system is designed to last the life of the vehicle without adjustment or replacement. High belt loads associated with operating 16 valves dictated a special high temperature rubber material and unique belt construction. A spring- loaded automatic tensioner with hydraulic damping forces an idler pulley against the back of the belt, maintaining proper tension for the life of the vehicle. Low inertia powdered metal sprockets, one for each cam, are spaced away from the block to reduce belt operating temperature. A two piece molded plastic cover completely encloses the belt to prevent damage from foreign matter. It includes a removable inspection plate.
Internal engine parts
Pistons are cast from a eutectic aluminum alloy that contains 12% silicon for wear resistance. They have an elliptical shape to control expansion during warm up to minimize noise and avoid low temperature scuffing. The pin is offset 0.04 in. (1 mm) to reduce noise. The tops of the pistons include valve clearance notches that allow increased valve lift. Piston pins are press-fitted into the rods. Ring line-up is conventional, with two compression rings and a three-piece oil ring.
Connecting rods and rod caps are initially formed as one-piece powdered metal forgings. Molding them from powder before forging assures excellent dimensional and weight control with minimum machining. Powdered metal rods are lighter than conventional forgings, especially at the piston end, resulting in low reciprocating weight and smooth high rpm operation. Weight is lower because the rods are made without the excess material that is partially machined away as part of the normal balancing process on conventional rods. The cap is separated from the rod by a unique process. The uneven surface that results from the breaking process provides perfect rod to cap alignment at assembly. Rod cap retention screws thread directly into the connecting rod for simplicity and light weight.
The nodular cast iron crankshaft is fully counterweighted -- it has counter weights on both sides of each crank pin -- to balance bearing loads for smooth, quiet operation yet weighs only 15 kg (33 pounds). Counterweights opposite each crankpin allow bearing diameters to be reduced from past practice for less friction aiding fuel economy and power. Main and rod bearings are 2.05 in. (52 mm) and 1.88 in. (48 mm) in diameter, respectively -- 0.4 in. (10 mm) and 0.15 in. (4 mm) smaller, respectively, than past practice. Main and rod bearing journal tolerances are reduced from past practice for quieter operation and longer life.
A conventional inertia-ring vibration damper is mounted on the nose of the crankshaft. Pulley grooves machined into the inertia ring drive the alternator and accessory belts. In addition to reducing engine noise and vibration, the damper reduces load variation on the belts for longer belt life.
The camshaft needs no bearing inserts: it operates directly in the cylinder head. Main and rod bearing shells are aluminum base material with a high load capacity.
Cooling Systems
The water pump scroll is integral with the block to reduce complexity. The pump is driven by the timing belt. The thermostat housing, cooling system filler neck, radiator hose nipple and overflow nipple are combined in a single cast aluminum part that attaches to the thermostat base on the cylinder head. The filler neck is on this housing rather than the radiator because the low hood line makes this the highest point in the cooling system and therefore the appropriate place for filling or refilling the system after maintenance or repair. A pressure radiator cap attaches to the filler neck. This cap maintains constant pressure in the cooling systems when the engine is running to enhance cooling and reduce water pump cavitation. This cap is smaller than a conventional radiator cap to avoid using an incorrect cap.
A check ball in the thermostat allows air in the coolant to escape when the system is cool but seals to assure rapid engine warm-up. The vent also aids in refilling the system after maintenance or repair by preventing air entrapment. By allowing air to escape, the vent also helps prevent large variations in coolant temperature during warm-up previously cause by trapped air.
The cast aluminum cylinder head cover has a black enameled finish. Raised nomenclature on the cover -- "DOHC 2.0L 16 Valve" -- has a silver finish.
Sealing Features
The crankshaft rear main seal is pressed into the block and bedplate assembly rather than into a bolt-on housing, eliminating a potential leakage path. The seal includes a Teflon(R) lip for long life.
The oil pump cover houses the crankshaft front main seal.
Oil pan and cylinder head cover gaskets are state-of-the-art molded silicone with steel backbones and compression limits.
Bed plate construction makes oil pan sealing easier by providing a flat, continuous, machined sealing surface.
The top surface of the cylinder head is machined flat for easy sealing.
Spark plug wells are sealed to the cylinder head covers by individual molded seals.
A molded silicone rubber gasket that is integral with the thermostat provides a high-integrity seal between the thermostat housing and cylinder head.
The oil pan drain plug includes a molded seal to prevent leakage.
The camshaft sensor is sealed to the cylinder head with an O-ring.
Fuel Injection System
Sequential multi-port injection uses injectors that direct a separate spray to each intake valve to provide balanced fuel delivery to all cylinders. Sequential injection improves throttle response and overall driveability compared to single-point or simple multiple-point injection.
The fuel injection system uses speed-density control -- engine speed and intake manifold pressure as primary determinants of fuel injection rate and timing. Intake manifold pressure is determined by a manifold absolute pressure (MAP) sensor. The injection system uses the same speed, timing and cylinder selection sensors as the ignition system. These direct-acting sensors provide both greater accuracy and quicker response than a conventional distributor.
The throttle body has a 2.05 in. (52 mm) bore to minimize restriction at high rpm. To enhance manual transaxle driveability, the throttle body has a contoured bore in the off-idle area that reduces the slope of the airflow vs. throttle angle curve making low-throttle "launches" easier. Also with manual transaxle, the throttle is operated by a progressive cam that provides relatively slow initial response to pedal movement. With automatic transaxle, the cam provides throttle response proportional to pedal movement.
Ignition System
The Avenger and Sebring 2.0-liter engine has a direct (distributorless) ignition system that provides the following benefits compared to distributor systems:
quick starts because camshaft and crankshaft sensors give early recognition of which cylinder is to be "fired"
simplification because the distributor and related parts are eliminated
greater accuracy because ignition and fuel injection timing signals are taken directly from the crankshaft and camshaft
reduced maintenance because timing adjustment is never required
improved idle quality because timing variation is reduced
improved engine response and idle quality because DIS sensors update data flowing to the PCM (power train control module) more frequently than conventional systems to accurately reflect changing speed and load conditions
high reliability through use of proven "Hall-effect" sensors
Two sensors provide data for operation of the system: a crankshaft timing sensor and a camshaft reference sensor. The timing sensor, which is inserted through the side of the block, senses two patterns of four slots each in the #2 crankshaft counterweight, spaced 180 degrees apart. These slots provide data for engine speed and timing calculations. Their position on the crankshaft establishes basic timing for the engine. Sensing directly from the crankshaft provides greater accuracy than prior systems that sensed from starter ring gear or torque converter drive plate. Individual slots are spaced 20 degrees apart. Spark advance and injection timing are computed from these points. One slot, called the "signature" slot, is 60 degrees wide; the others are approximately 5 degrees wide. The unique sensor output coming from the signature slot is used in combination with the output from the camshaft sensor to determine which cylinder is ready for fuel and ignition.
The camshaft sensor is mounted at the rear of the exhaust camshaft, outside the cylinder head. It is triggered by a ring magnet in the end of the camshaft. The magnet has four poles arranged asymmetrically at 150 degree and 210 degree intervals. Correlation between the magnet poles and the "signature" slot is established in less than one crankshaft revolution, allowing injection and ignition to begin.
A knock sensor permits fine tuning of engine operation rather than just responding to engine-damaging knock.
The four-lead DIS coil module is attached directly to the cylinder head cover, providing very short secondary wire leads.
Idle speed control
The PCM determines idle speed. It actuates a stepper motor and by-pass valve in the throttle body to change idle air flow. In addition to customary warm-up and basic idle speed control, a switch on the power steering high-pressure hose detects higher hydraulic pressure that occurs during steering action and compensates by increasing idle speed. Air conditioning compressor operation has the same effect. To maintain smooth operation, the PCM idle speed control system opens the valve in anticipation of compressor engagement or (with automatic transaxle) a shift out of Neutral.
Other Components
The generator is driven by a poly-vee belt from the crankshaft damper. The power steering pump and air conditioning compressor are driven by a separate poly-vee belt. The belt is also adjusted manually by means of a pivoting bracket.
A lightweight two-piece plastic air cleaner housing is remotely mounted and houses a panel-type filter. Air is ducted to the throttle body by a flexible molded hose.
To minimize oil pullover at high rpm, the crankcase ventilation system includes an oil separator in the cylinder head cover. The separator has baffles that inhibit the flow of oil to the intake manifold. Oil drains out of the baffling on a long, narrow plate pinned to the inside of the cover.
The optional automatic speed control system uses a vacuum servo supplied by manifold vacuum to open the throttle via cable. It allows the car to maintain any selected speed between 35 to 85 mph (56 to 137 km/hr.) A vacuum reservoir helps operate the servo on steep grades. An intermediate link between the speed control cable and the throttle cable allows the driver to increase speed, if desired, independent of speed control operation. The system cancels speed control action if the brake is applied, if engine or vehicle speed rises quickly indicating wheel spin or an out-of-gear condition, or if vehicle speed drops suddenly, indicating rapid deceleration.
No comments:
Post a Comment