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1980-1981 Turbo Trans Am
The little turbo engine every 455 and even 400 owner LOVES to HATE!
The following is an article paraphrased from noted author Gary Lisk.
Pontiac at the end of the ‘70’s found themselves in an awkward position, one of government EPA regulations and a “gas shortage”, what were they to do? They had a reputation of bravado and horse power to hold up and Pontiac engineers tried their best with the technology available to live up to that reputation so established.
They decided the best option was…to Turbo charge their little 301 V8. For an engine that began life as an economy motor, numerous modifications were in order if the engine which was designed to operate in a vacuum to live under the pressure of a mere nine pounds of boost, nothing by today’s standards but with the gas of the day, it was asking a lot, more on that later. The webbing around the main bearing caps on the block was made thicker. Head gasket materials were upgraded to keep the pressure within the cylinder bores. Main bearing cap bolts were up a size from 7/16 of an inch to an honest one-half inch. Pistons were made stronger and the wrist pins tougher to survive the stresses forced induction imposed.
The turbocharger chosen to "boost" the power of the 301 was the same Garrett TB305 unit which was in service in the Buick and Ford turbo engines of the time but not on any V8’s. The turbocharger plumbing utilized a "draw through" design, where the boost took place behind the carburetor. Although, at best, this was a compromised design because the turbocharger did not get to work to the full potential. But these were the days before fuel injection, and GM could not risk the possibility if a forced induction fuel leak. Compared to the other turbos on the market the T/A motor lacked most of the whine associated with turbocharged engines. Pontiac asked Garrett to provide better balanced turbo impellers to reduce the noise. The idea was to make the turbo as transparent as possible, to use the feel of the acceleration rather than the noise of the turbo to let the customers experience the power at hand.
The net output of the turbocharged 301 (Engine Code "YL") varied but was generally cited as being 210 horsepower at 4000 rpm, down a mere 10 horsepower from the mighty T/A 6.6 engine laid to rest after the '79 model year. Bolting on the turbocharger bumped the torque up to 345 lb/ft @ 2000 rpm, a 25 ft/lb increase over the T/A 6.6L engine. The compression ratio of the engine was lowered to 7.5:1 and was fitted with a derivative of GM's Buick electronic control unit to monitor boost and timing settings. Maximum boost was achieved at around 3500 rpm, a little below the shift point.
The turbocharger was a grand idea, but the technology to make it really work properly was nonexistent at the end of the 70's. As the newer high octane fuels we have today were not yet available, the engine had to operate on substandard fuels (Sunoco 94, and the like, were nowhere to be found) of 87 to 90 octane, and this would have led to severe detonation under boost if it were not for the ECU. By placing a vibration sensor in the valley between the cylinders which would detect detonation, the ECU interrupted this chain reaction by retarding the ignition timing and reducing boost pressure until the detonation was gone. By utilizing these computer controls, this process was repeatedly continued during the operation of the engine, attempting to keep the engine running at optimum performance all the time. By eliminating so much timing, the result was a none-too-powerful feeling from the turbo engine. With today's fuels, many owners claim quite reasonable performance and many of these engines have lived well beyond the 150,000 mile mark with little other than routine maintenance. This writer himself knows of one such example.
The effects of the timing adjustments were so severe that the required automatic transmission was programmed to upshift at 4400 rpm for the 1-2 shift and at 3800 for the 2-3 shift, 200 rpm short of the engines power peak. This was also the point at which the car was the quickest because manually shifting the transmission at higher rpms gained no speed or quickness, just noise.
The turbo 301 introduced the quite attractive "turbo hood", making these the first Trans Ams since the '69's to not have a shaker hood. The hood had about a 22 inch bulge that extended upwards 1 and 1/4 inches that was offset to the left of the hood centerline. Clearance for the relocated carburetor and plumbing from the turbocharger necessitated this bulge (much as the planned 2-4bbl's on the '70 T/A resultant shaker). Underneath, a hood blanket (the first such application on the Trans Am) had a aluminized shield over the turbocharger area in an attempt to keep the hood paint from blistering. To make things interesting, a "Turbo Boost Gauge" (RPO UR4) could be ordered for $40 and consisted of a series of three orange lamps which showed the rate of boost the engine was operating under and was located at the rear of the bulge facing the driver. No real (one that showed the actual amount of boost) boost gauge was offered on the Turbo Trans Ams.
The Pontiac 301 (Engine Code YN or XN) was the standard engine for all Trans Am's outside of California and was equipped with a 4-bbl carburetor. Referred to as a 4.9 liter V8 to distinguish itself from the Chevrolet (5.0L/305 CID), this was the engine Pontiac's had developed purely for economy. The engine had a bore of 4.00" and a stroke of 3.00" (ironically the same as Ford's 302 and Chevrolet's mighty 67-69 302 cid Z28 engine) and produced 150 hp at 4400 rpm and 235 lb/ft of torque at only 1800 rpm, up five horsepower from 1979 benefitting from a slightly hotter cam and a revised exhaust system. By a lot of these numbers the 4.9 and the 4.9 liter Turbo, could, COULD, be a very hot little package had it not been for just a couple of key factors limiting the flow (we call them, cylinder heads) to create an economy motor…before it was decided to create an economy motor that had some power.
As the new engine package was the highlight to the 1980 model year, there were only minor color, trim, accessory, and feature changes. Chassis wise, there were low friction ball joints, helping to make the ride smoother. To aid in overall durability, the power steering pressure hoses had new "O" rings at the connections to reduce the opportunity for leaks. In a move that in the 80' was the "wave of the future, the steering linkage studs and nuts converted from "standard" to "metric". Ugh…
Trans Ams could now be ordered with a widening array of luxury items in attempt to broaden its appeal to those who were interested in the performance image of the car, but did not want to sacrifice the creature comforts of other cars in the same price class. These included new digitally tuned stereo radios, additional acoustical insulation packages, and a new seat covering style.
Inside, there were few detail changes. The base seats were still finished in Oxen vinyl, but the headrests were no longer pleated to match the remaining seating surface. Custom interior was still available, either in Doeskin vinyl or in Hobnail cloth. The speedometer was changed, abiding by new federal laws which limited the speedometer to 85 mph.
The big change to the outside of the Trans Am was the earlier mentioned "Turbo Hood", offered only with the 4.9L Turbo engine. Trans Am's equipped with the 4.9L or the 5.0L V8's still featured the shaker scoops. Two styles of optional hood decals (RPO D84) were offered; the conventional appearing bird when ordered in combination with the 4.9L or 5.0L engines or the "Turbo Bird" when equipped with the 4.9L turbo. The "Turbo Bird" turned the Firebird's head to the left and spit out a larger flame than the "regular" Firebird.
Last year's 10th Anniversary Edition "Turbo" cast aluminum wheels (RPO N89) were initially showcased on only those Trans Am's ordered with the 4.9L Turbo (RPO LU8) engine (which also required the WS6 or WS7 suspension packages). This idea was short lived because Californians, who were not allowed the turbo in their smog encumbered state, wanted the turbo wheel. Pontiac abided by their wishes lifted some of the restrictions, and allowed 305's and even some non-turbo 4.9L engined cars to be produced with the "Turbo" wheels. The wheels could be ordered in either the natural polished finish or in a gold painted version, with the edges on the gold painted versions being machined away. All wheels were fitted with a bright plastic center cap with the Firebird logo mounted in the center.
To prove the Turbo Trans Am's viability as a big engine replacement, the 1980 Indianapolis 500 would be paced by the first time in history by a Firebird. Eager to showcase the little turbo's ability, the engine and drivetrain would be stock, (but most likely blueprinted). The changes were limited to a rear axle ratio swap, utilizing a 2.56:1 versus the standard 3.08:1 gearing, and a larger P245/60R15 Goodyear Eagle GT tire. The taller gearing allowed the engine to operate in the 3500-4000 rpm range rather than 45-5000 rpm, exhibiting much less stress at the continual high speeds the pace car would be operated at. Pontiac built five cars for the track and the actual Pace Cars were built without air conditioning.
In what has become a popular move, Pontiac produced 5700 Turbo Trans Am Indy 500 Pace car replicas, complete with stickers and decals to make it look just like the rear thing. Outside, the car was painted in a similar style to the 10th Anniversary Trans Am, with white replacing the silver complemented with gray accents. The "Turbo" cast aluminum wheels were painted white to match the exterior and had many areas machined away exposing the natural aluminum as had been common practice on the "Snowflakes". The exterior mirrors were painted gray and were given a dual black/red pinstripe which also followed many of the detail lines on the car. The hood bird was an exaggeration for the optional new for 1980 Turbo hood bird with the wing tips stretching to nearly the front fenders.
Inside the seats were finished in a combination of Doeskin vinyl and Hobnail cloth in the hue of oyster with black accents. In the center of the rear seatback, a Firebird logo was stitched into the vinyl trim, with the logo also being stitched into each door panel. The red-lit gage cluster from the 10th made its way into the Pace Car.
The Indy 500 Pace Car replicas, because ot the standard 4.9L turbocharged engine, were excluded from sales in California due to the emission requirements. Pontiac laid claim upon announcing the Pace Car Replica that this car was the first and only production car with a Turbocharged V8 as standard equipment.
Additional cars saw pace car duty. Daytona Motor Speedway used Turbo Trans Ams to pace the Firecracker 400. These cars were all single color and used the natural finish turbo cast aluminum wheels.
Prices for the Trans Ams jumped sharply from 1979 prices to the 1980 model year, due to the difficult inflationary times in America and the popularity of past models. The Firebird Tran Am base price increased by $880 to $7,179 despite losing the 403 cid engine as standard equipment. To step up to the RPO LU8 Turbocharged 4.9L engine added $350 to the price and the RPO Y84 Special Edition package commanded a $1443 premium with T-Tops and $748 without. The Indy 500 Pace Car replica with the 4.9L turbo standard carried a list price of $11,194.
Without a doubt, 1980 was a turning point for the Trans Am as well as the entire Firebird line. What we all call “classic” styling today was referred to by some as a "dinosaur" in its day. What a shame. 1981 was just around the corner and many were joyously awaiting the demise of the proud automobile so they could get their hands on the replacement. The 1981 Trans Am would be the last of the line.
1980 Turbo Pace Car Specifics 4.9L Turbocharged V8 Engine, 3-Speed Automatic Transmission, Positraction rear axle with 3.08:1 axle ratio, WS6 Performance Handling Package with 4-wheel disc brakes, Hatch roof, Specific Oyster interior with Hobnail Cloth inserts in Doeskin Vinyl with Firebird logo embridered into rear seat back, special oyster luxury weight carpet, Air conditioning, Red lit gages, power windows, power door locks, power antenna, white exterior color with gray accents, unique hood decal, turbo boost gauge, white painted turbo cast aluminum wheels, leather stitched formula steering wheel with unique horn button, pin striping, custom interior door trim panels with Firebird logo embroidered into each upper panel, tilt steering wheel, delay wipers, and cruise control.
Well, for 1981, the Pontiac Firebird Trans Am entered it's eleventh year of production, the past ten in the F-body that made its appearance as a '70 1/2 model. There were few changes made to the Trans Am for it's final year, most of which were of the continuing quality improvements and upgrading of standard equipment levels.
As had been witnessed with the 1980 offering, small displacement engines were the order of the day. The highly desirable (for its time) 4.9L Turbocharged Pontiac V8 made its return. The big V8's were, of course gone, never to return.
The T/A 4.9L would stay in production until around April, after that, Pontiac would no longer be a source of V8 engines. With the introduction of the brand new third-generation T/A, only Chevrolet (later referred to as GM Corporate) engines would be found under the hood of Trans Ams (if you thought the 301 was a shame, you were wrong because THIS was a crying shame). In its last year of the second gen. the 4-bbl carburetor still powered the 4.9L engine, and again the only transmission available was the automatic. Engine codes for the T/A 4.9 were BD or BJ.
All turbos got the "boost gauge", the set of three lights in the hood bulge. The hp ratings dropped to 200 but even at 200 hp, this would still be the highest horsepower rating for a Trans Am until the debut the Tuned Port engines in 1985. For the 4.9L turbo, there were two engine codes, BO or CJ.
The performance car market was once again in the same doldrums they survived with the introduction of the catalytic converter in 1975. Performance had rebounded in the ensuing years, only to have ever tightening Federally mandated fuel economy minimums take it back. Pontiac was still trying though. They still had the “World’s Only Turbocharged V8” and they did reintroduce the manual transmission…on the corporate engine, but in comparison to the glory days, the Trans Am still came up a little short.
The Trans Am was not without the handling and styling flair that on which part of the marques reputation had been built. The spoilered 'Bird still looked better than any of it's competitors and the handling took a back seat to no one, regardless from which continent that auto originated. All Trans Am's were fitted with P225/70R-15 steel belted radial tires regardless of which suspension package was fitted. The base cars were equipped with either 7" wide steel Ralley II's or cast aluminum snowflakes. Those with the optional WS6 or WS7 (without rear disc brakes) suspension packages received the 8" wide snowflakes or turbo cast aluminum wheels. For some reason Pontiac decided 1981 would be the year to break tradition and not offer the Limited-slip rear differential as standard equipment. Maybe just a statement...the end is near?
All Trans Ams received GM's new "Computer Command Control", an early version of today's high tech computer controlled engine but for many years known as a “trouble maker” and got removed from the cars. GM outfitted the engines with sensors to measure engine temperature, engine speed, the throttle position, barometric pressure, and the oxygen content in the exhaust. The computer would then analyze the readings and adjust the air-to-fuel ratio to increase the efficiency by not letting the engine run too rich, and also reducing emissions. A new, lighter weight Delco Freedom II battery rounded out the electrical package.
The color palate was as strong as ever with thirteen colors now available. The hood decal, was still bold, continuing to spit fire.
Special Edition Trans Ams were still around, wearing their black tuxedos set off with gold pinstriping and accents. Pricing for the Y84 package held fairly steady at $779 without and $1,516 with t-tops, only a $31 / $73 increase of the 1980 version. Continuing to climb however, was the base price which had lept to $8,322, a $842 increase over the 1980 version.
In keeping with a tradition established in 1979 with the 10th Anniversary model, the Trans Am featured a "NASCAR" edition. The paint scheme mirrored the previous '79/'80 style but was black over white. Inside there were some big changes. The Trans Am seats, which had been largely unchanged since 1971 were replaced with a set of Recaro buckets. Red inserts in the seating area contrasted with the black bolsters and seatbacks. The rear seating area was finished in the same pattern. The Recaro's held the driver and front seat passenger in place with seat design rather than upholstery selection. Finally, after 11 years of complaining, the Journalists and consumers received, in the NASCAR edition, what they had been asking for, for years - a seat back adjuster!
All NASCAR Trans Ams were turbocharged and featured white turbo cast aluminum wheels. At the rear flanks, there were large "NASCAR" logos, with additional logos underneath the Trans Am decals on the fenders.
All in all, the second generation Trans Am had a great run. After a rocky start, 458,462 were built during the eleven year run. Starting at 3,196 examples in 1970, to its 116,535 unit peak in 1979, and ending 1981 production with an additional 33,313 Trans Ams. These numbers would have made any manufacturer happy. There are Trans Am Websites (namely AllGenTransAms.com), clubs, entire industries (see AllGens sponsor list), owners, and Police Officers, and Movies all who recognize the important role the Second. Gen. and the Turbo Trans Am played.
for Production Numbers and photographs of the '80 and '81 Turbo T/A cars,
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