Chevrolet Corvair engine is a flat-6 (or BOXER engine) piston engine used exclusively in the 1960s Chevrolet Corvair automobile. It was a very unusual engine for General Motors: It was air-cooled, used a flat design with aluminum heads (incorporating integrated intake manifolds) and crankcase, and individual iron cylinder liners. The heads were modeled after the standard Chevrolet OHV large valves operated by rocker arms, actuated by rods to launch nine camshaft lobe (exhaust lobes has a dual role for the two opposed cylinders) running directly on the crankcase bore without an inserted bearing, operating hydraulic valve lifters (which eliminated low-temperature valve noise otherwise seen with so much aluminum in the engine because of its high thermal expansion coefficients).
The flat boxer engine (flat engine air cooled) engine design, previously used by Volkswagen and Porsche, and Lycoming engines, offered many advantages. Unlike inline or V designs, the boxer engine design, the mechanical balance itself, so that the counterweights on the crankshaft is not needed, the weight is reduced significantly. The elimination of a water cooling further reduces the weight and use of the aluminum head and crankcase enabled on this weight, so that the use of aluminum in the event deck, engine transmission / transaxle Assembly under weighed 500 pounds (225 pounds). In addition, the elimination of cooling water in several points of maintenance and errors are eliminated, making it all on a single point, the fan belt. As for Volkswagen and Porsche design, lightweight and compact, but big packages ideal for mounting the engine in the rear of the car, making the weight and space of a tree ‘classical training.
Two years after its inception in 1960, won the engine Corvair unusual attribute: it was the engine of the second largest production plant to be equipped with a turbocharger, shortly after the Oldsmobile Jetfire V8 released.
lovers and small aircraft manufacturers, may see the similarity engine Corvair Lycoming, quickly began a cottage industry change of Corvair engines for aircraft, which continues to this day. The Corvair engine also became a favorite for the installation of a modified Volkswagen and Porsche, as well as dune buggies and sports cars and home race.
140
The innovative engine Corvair turbo, turbo floor, top right is becoming the top air filter general air left, it goes into the carburetor sidedraft between, and feeds pressurized fuel / air mixture into the engine through the chrome T-tube spans the engine visible from left to right.
The innovative engine Corvair turbo, turbo floor, top right is becoming the top air filter general air left, it goes into the carburetor sidedraft between, and feeds pressurized fuel / air mixture into the engine through the chrome T-tube spans the engine visible from left to right.
The first Corvair engine displaced 140 in ³ (The second product 3) and 80 (kW 60). The high performance optional “Super Turboair introduced version” in mid-1960 with a special camshaft and revised carburetors and valve springs produces 95 hp (70 kW).
145
In 1961, the engine its first increase in size has received a larger diameter. The engine was now 145 in ³ and was the base engine said to produce the same 80 hp (60 kW). The new high performance engine was rated at 98 hp (73 kW). In 1962, the high performance engine was rated at 102 hp was (76 kW). The high compression 102 heads were the HP is equipped with Powerglide Monza, where the standard engine was ordered, is an engine output of 84 hp. 1962 engines returned to automatic chokes after a year in 1961 choking on manual models.
The ultimate performance was found in the model Spyder, which was available with a turbocharged 150 hp (112 kW). The turbocharger is mounted on the right side of the firewall behind the rear seat, fed by both exhaust manifolds, carburetor sidedraft one mounted on the left side of the firewall directly supplied to the turbocharger intake leads with chrome pipe making turbocharger that otherwise the carburetor mounting plates on the intake pipes of water that are part of the leaders were. The turbocharged heads received some valve upgrades to improve durability. exhaust valves for turbo engines are non-ferrous materials in jet turbine blades, used called “Nimonic 80 A ‘. All other Corvair engines had slight upgrades are in the valve and valve seat material and for 1962.
164
The engine has been (past the second 6-2 94 “) to move 164 (2 7 L) for 1964. Power 95 hp (70 kW) for the base model and 110 hp (80 kW) motor Induction of high performance, while the turbo engine of 150 horses has been noted for this year will be increased. The increase was the maximum stroke of the engine can tolerate, to be notched so that the bottom of the cylinder barrels had until ‘at the end of the great rods from clear.
For 1965 model year, all engines had the head gasket area between the cylinder and increases the head with a new design folded “Z” section stainless steel head gasket virtually eliminates the risk of head gasket failure. A 140 hp (104 kW) version with 4 single barrel carburetors and a progressive association was established in 1965, L63 option “special high-performance engine” and was introduced as standard model Corsa. Carburetor was a single barrel primary and secondary one pass on each head, connected by a gradual, also made heads ninth 25:1 compression, and the cars dual exhaust systems. Motors supplied with the automatic transmission after spring 1965 were modified with a camshaft of an engine of 95 horsepower basic and special equipment, slowing time the crankshaft 4 degrees of torque about the good old and idle with the Powerglide transmission, it to raise again some of the top high-speed HP lost by the economy profiled camshaft timing short.
1966 vehicles were mainly the transfer of 1965, but the Corvair model sold in California (except turbo model) is now present in General Motors Air Injection Reactor System (IAB) and the emission control system, because composed of an air pump motor, air filter, and drew the air filter and injecting a quantity measured in the exhaust manifold through tubes to oxidation and complete combustion of waste gases to promote reducing emissions. Specially calibrated carburetors and slight changes to the ignition advance curves and were part of the package. The AIR system had an unfortunate effect observed sustantially exhaust valve and head temperatures, particularly under heavy loads and was a disadvantage, if not on the Corvair engine cooling could easily be improved to cope with higher temperatures. However, the performance and handling are not significantly in most cases made. In 1968, I lost all Corvair GM (and other) engine air system for each market.
The 140 HP engine was officially over 67, but was optional in 1967 COPO 9551-B, not a regular production option. Chevrolet sold 279 of these engines in 1967, 232 with manual transmission and 47 with Powerglide transmissions. Only six have been with the engine with four carburetors and sold the air injection system required by the California emission. These figures include 14 Yenko Stingers and 3 Dana Chevrolet Stinger variants.
The two engines of 140 hp turbocharged engines had many special qualities not shared with less Corvair Moly insert top rings, advice and faces on stellite valves, tightening Tufftrided (cold gas) of the crankshaft aluminum engine and Delco Moraine ‘400 ‘Having the quality of the 140HP Corvair engine materials is directly comparable to the V8 Rolls Royce at the time, the position of the position. It was a good deal for the $ 79 premium it commanded on the engine 95hp base. Engine performance was better than 140p you can imagine, with a peak 5200 rpm power, it offered road performance in a Corvair comparable to contemporary Cadillac models of the day.
The turbocharged engine now develops 180 hp (134 kW). contemporary reviews describe a similarity between the power and four-engine turbo carburetor through the low to mid speed range, to think with the turbo engine as if it were possible to increase to maintain continuously maintained. The turbocharged engines long trial has been accelerated Highway, floor of the accelerator at speeds of acceleration Turnpike wild products in the upper rpm range began to increase as the turbocharger, the multiple pressures approach reaches 15 psi. No wastegate was used on the Corvair turbocharged engine, increase was a balance between control of exhaust restriction, mainly used on exhaust and intake restrictions from the smallest of the Carter Carburetor YH. The pre-ignition and knock under increase was monitored using pressure to delay “a novel device, essentially a modification of the vacuum advance on the distributor specially curved as boost pressure was constructed by gradually reducing the spark advance detonation contrary.