TRANS AM WORLD








Pontiac Firebird



Thanks to PHS Online for some of these statistics.


1970 Pontiac Firebird






Comments: An all new Pontiac Firebird was introduced for 1970 and represented a new high for Pontiac styling. The front bumper and grille were molded out of Endura rubber and were painted the same color as the car to give it a bumperless appearance. The sides sported rounded full wheel cut outs without any extra trim (the Camaro had more squared off wheel cut outs). The suspension was revised and a rear stabilizer bar was added. The Firebird lineup was reduced from six to four, and the convertible was eliminated. At the bottom of the line up was the Base Firebird, whose Pontiac 250 I6 was replaced by a Chevy built 250 I6 rated at a meager 155bhp. Next up was the Espirit, which featured the Pontiac 350 V8 rated at 255 bhp. The Formula 400 featured a unique twin-scooped hood with a 400 V8 rated at 335 bhp. At the top was the Trans Am, which was fitted with air dams across the bottom of the front and in front of the wheels. A large decklid spoiler and small spoilers in front of the rear wheels completed the package. These aero pieces were claimed to generate 50 pounds of downforce on the front and rear of the car at highway speeds. Trans Ams also received a rear facing shaker hood scope to feed the standard Ram Air II engine. Optional on the Trans Am was the Ram Air IV engine, whose output had increased to 370 bhp due to bigger ports, better heads, swirl-polished valves, and an aluminum instake manifold. Only 88 copies were made. Rarer still was the Ram Air V, an over-the-counter, special order engine that included solid lifters and tunnel port heads and made up to 500 bhp. A four speed Hurst shifter was standard, but a three speed Turbo Hydra-matic automatic was available. Inside, complete instrumentation, including a tach turned on its side to red line at 12 o'clock just like a race car, completed the performance image. The Trans Am featured one of the best tuned suspensions of any car (including the Corvette) and its European styling gave it instant class. The Trans Am was now available in either Polar White or Lucent Blue, with contrasting stripes, a relatively modest bird stencil at the tip of the nose, and the words "Trans Am" across the rear spoiler.

Production:   Trans Am: 3,196
                      Formula 400: 7,708

There were 689 RA Formulas made in 1970. 
293 were M40 automatics
15 were M13 3 spds
192 were M20
189 were M21 
Those with M21 got the 3.73 rear end and no A/C.


PONTIAC FORMULA PRODUCTION FIGURES
ENGINE MANUAL AUTOMATIC TOTAL
WT M21 n/a 458
WT M20 n/a 1637
WT M13 n/a 286
- - - -
WS M21 n/a 189
WS M20 n/a 192
WS M13 n/a 15
- - - -
YZ M40 n/a 293
- - - -
YS M40 n/a 4638


1970 PONTIAC TRANS AM PRODUCTION FIGURES
ENGINE MANUAL AUTOMATIC TOTAL
WS 1,769 - 1,769
WW       59 -       59
YZ - 1,339 1,339
XP -       29       29
------------- ------- ------- -------
TOTAL 1,828 1,368 3,196

WT = L78 400 (manual transmission engine)
YS = L78 400 (automatic transmission engine)
WS = L74 400 "RAM AIR III" (manual transmission engine)
YZ = L74 400 "RAM AIR III" (automatic transmission engine)
WW = L67 400 "RAM AIR IV" (manual transmission engine)
XP = L67 400 "RAM AIR IV" (automatic transmission engine)



Engines:
250 I6 155 bhp.
350 V8 255 bhp.
400 V8 265 bhp.
400 V8 330 bhp @ 4800rpm, 430 lb-ft @ 3000 rpm.
400 V8 (HO) 335 bhp @ 5000rpm, 430 lb-ft @ 3400 rpm.
400 V8 (Ram Air III) 345 bhp @ 5000 rpm, 430 lb-ft @ 3400 rpm.
400 V8 (Ram Air IV) 370 bhp @ 5500 rpm, 445 lb-ft @ 3900 rpm.
400 V8 (Ram Air V - over the counter) 500bhp.
Performance: 400/370 (RA IV): 0-60 in 5.6 sec, 1/4 mile in 13.9 sec @ 102 mph.

1970 Pontiac Firebird Trans Am 400 CID Ram Air III
Manual Transmission Engine Specifications

Engine Code

WS

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

10.5:1

Horsepower @ RPM

345@5000

Torque (Lb/Ft) @ RPM

430@3400

Head Casting

12

Carburetor

4-bbl

Carburetor - Federal

7040273

Carburetor - Calif

7040573

Intake Manifold

9799068

Camshaft

Part #

9779068

Lift, I/E

.410 / .413

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

288 / 302

Overlap - Degrees

63

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifolds

R 9799720

Exhaust Manifolds

L 478140

Distributor

1112024

1970 Pontiac Firebird Trans Am 400 CID Ram Air III
Automatic Transmission Engine Specifications

Engine Code

YZ

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

10.5:1

Horsepower @ RPM

345@5000

Torque (Lb/Ft) @ RPM

430@3400

Head Casting

12, 13

Carburetor

4-bbl

Carburetor - Federal

7040270

Carburetor - Calif

7040570

Intake Manifold

9799068

Camshaft

Part #

9779068

Lift, I/E

.410 / .413

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

288 / 302

Overlap - Degrees

63

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifolds

R 9799720

Exhaust Manifolds

L 478140

Distributor

1112009

   

1970 Pontiac Firebird Trans Am 400 CID Ram Air IV
Manual Transmission Engine Specifications

Engine Code

WW,WH

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

10.5:1

Horsepower @ RPM

370@5500

Torque (Lb/Ft) @ RPM

445@3900

Head Casting

614

Carburetor

4-bbl

Carburetor - Federal

7040273

Carburetor - Calif

7040573

Intake Manifold

9799084

Camshaft

9794041

Part #

9794041

Lift, I/E

.527 / .527

Rocker Arm Ratio

1.65:1

Duration I/E - Degrees

308 / 320

Overlap - Degrees

87

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifolds

R 9799721

Exhaust Manifolds

L 478141

Distributor

1112013

1970 Pontiac Firebird Trans Am 400 CID Ram Air IV
Automatic Transmission Engine Specifications

Engine Code

XP,XN

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

10.5:1

Horsepower @ RPM

370@5500

Torque (Lb/Ft) @ RPM

445@3900

Head Casting

614

Carburetor

4-bbl

Carburetor - Federal

7040270

Carburetor - Calif

7040570

Intake Manifold

9799084

Camshaft

Part #

9794041

Lift, I/E

.527 / .527

Rocker Arm Ratio

1.65:1

Duration I/E - Degrees

308 / 320

Overlap - Degrees

87

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifolds

R 9799721

Exhaust Manifolds

L 478141

Distributor

1112013



1971 Pontiac Firebird






Comments: 1971 saw little styling change for the Pontiac Firebird, with the addition of high-back bucket seats being the major appearance change. In order to satisfy General Motors decree that all engines had to run on unleaded gasoline to meet federal emission standards, the engine options were significantly altered. A new 400 V8 rated at 300 bhp was added, but both 400 Ram Air engines were dropped. In their place were two new 455 V8s, rated at 325 bhp and 335 bhp. The 455 HO engine was the only engine available in the Trans Am and borrowed the cylinder heads (with larger combustion chambers) and the intake manifold from the 1970 Ram Air IV. The Trans Am continued with its blue and white paint scheme, functional rear facing engine shaker hood scoops, and aero body pieces. Although the 455 engines available in the Trans Am were less powerful than the 1970 Ram Air IV engine, their 480 lb-ft of torque and less tempermental nature made them easier to drive on the street and were one of the high points in a time when performance was on the decline.

Production:  Trans Am:  2,116
                     Formula:    7,802


PONTIAC FORMULA PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Formula 350/400 1694 5437 7131
Formula 455 NONE 350 350
Formula 455HO 166 * 155 321
---- ---- ---- ----
Total Firebird Formula 1860 5942 7802

*Of those 166 455HO/MT Formulas - seven of them were M13 Cars.

1971 PONTIAC TRANS AM PRODUCTION FIGURES
ENGINE MANUAL AUTOMATIC TOTAL
WC 885 - 885
YE - 1,231 1,231
------------- ------- ------- -------
TOTAL 885 1,231 2,116



Engines:
400 V8 300 bhp @ 4800rpm, 400 lb-ft @ 3600 rpm.
455 V8 325 bhp @ 4400 rpm, 455 lb-ft @ 3200 rpm.
455 V8 (HO) 335 bhp @ 4800 rpm, 480 lb-ft @ 3600 rpm.

Performance: 455/335 (HO): 0-60 in 5.9 sec, 1/4 mile in 13.9 sec @ 103 mph.

1971 Pontiac Firebird Trans Am 455 CID H.O.
Manual Transmission Engine Specifications

Engine Code

WL, WC

Engine RPO

LS5

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.4:1

Horsepower @ RPM (Gross)

335@4800

Horsepower @ RPM (Net)

310@4800

Torque (Lb/Ft) @ RPM (Gross>

480@3600

Torque (Lb/Ft) @ RPM (Net)

410@3600

Head Casting

197

Carburetor

4-bbl

Carburetor - Federal

7041267, 7041273

Camshaft

Part #

9779068

Lift, I/E

.408 / .406

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

288 / 302

Overlap - Degrees

87

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Distributor

1112073

   

1971 Pontiac Firebird Trans Am 455 CID H.O.
Automatic Transmission Engine Specifications

Engine Code

YE, YA

Engine RPO

LS5

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

10.5:1

Horsepower @ RPM (Gross)

335@4800

Horsepower @ RPM (Net)

310@4800

Torque (Lb/Ft) @ RPM (Gross)

480@3600

Torque (Lb/Ft) @ RPM (Net)

410@3600

Head Casting

197

Carburetor

4-bbl

Carburetor - Federal

7041268, 7041270

Camshaft

Part #

9779068

Lift, I/E

.527 / .527

Rocker Arm Ratio

1.65:1

Duration I/E - Degrees

308 / 320

Overlap - Degrees

87

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Distributor

1112073



1972 Pontiac Firebird






Comments: 1972 was a disasterous year for the Firebird. GM executives considered dropping the Firebird altogether as sales fell drastically as the muscle car market collapsed, which was worsened by a crippling 174 day strike at the only plant that produced Firebirds. Pontiac executives were able to eventually save the Firebird and it continued, with very little change from 1971, except that its engines were now rated in net SAE numbers. Pontiac's famous "honeycomb" wheels also made their first appearance in 1972.

Production: Trans Am:  1,286
                     Formula:    5,249


PONTIAC FORMULA PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Formula 350 ? ? 2544
Formula 400 ? ? 2429
Formula 455HO ? ? 276
---- ---- ---- ----
Total Firebird Formula 1082 4167 5249


1972 PONTIAC TRANS AM PRODUCTION FIGURES
ENGINE MANUAL AUTOMATIC TOTAL
WM / WD 458 - 458
YB / YE - 828 828
------------- ------- ------- -------
TOTAL 458 828 1,286


Engines:
400 V8 250 bhp @ 4400rpm, 325 lb-ft @ 3200 rpm.
455 V8 300 bhp @ 4000 rpm, 415 lb-ft @ 3200 rpm.

Performance: N/A

1972 Pontiac Firebird Trans Am HO 455 CID
Manual Transmission Engine Specifications

Engine Code

WD, WM

Engine RPO

LS5

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.4:1

Horsepower @ RPM

300@4000

Torque (Lb/Ft) @ RPM

4150@3200

Head Casting

7F6

Carburetor

4-bbl

Carburetor - Federal

7042273

Intake Manifold

488945

Camshaft

Part #

9779068

Lift, I/E

.408 / .406

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

288 / 302

Overlap - Degrees

63

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Distributor

   

1972 Pontiac Firebird Trans Am HO 455 CID
Automatic Transmission Engine Specifications

Engine Code

YB, YE

Engine RPO

LS5

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.4:1

Horsepower @ RPM

300@4000

Torque (Lb/Ft) @ RPM

415@3200

Head Casting

7F6

Carburetor

4-bbl

Carburetor - Federal

7042270

Intake Manifold

488945

Camshaft

Part #

9779068

Lift, I/E

.408 / .406

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

288 / 302

Overlap - Degrees

63

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Distributor





1973 Pontiac Firebird






Comments: 1973 saw some significant new changes to the Firebird, including a new eggcrate grille and a revised front bumper. Engine ratings were down again, with the 350 rated at a mere 150 bhp and the 400 at 250 bhp. But two things would save the Firebird and firmly establish Pontiac as the performance manufacturer during the dark days of the 1970s. The first was the introduction of a new Super Duty 455 V8 (SD-455). "Super Duty" was the name Pontiac used on its high performance (i.e. race ready) engines in the early 1960's, and the Super Duty 455 was a street legal race prepped engine. All SD-455's were hand assembled, and had a reinforced block, casting provisions for a cam driven dry sump on back of the block, special cam shaft, aluminum forged pistons, oversize valves and header-like exhaust manifolds. Pontiac originally rated the SD-455 engines at a stout 310 bhp and 390 lb-ft, but experts agreed that it was closer to 370 bhp. The camshaft wouldn't pass emissions so they put a milder cam in with a 290 HP rating. This level of engine ratings were unheard of in an era when other manufacturer's engines' output were falling dramatically, and the Firebird became the only true performance car remaining in the market. Unfortunately, Super Duty engines were expensive and therefore rare; only 252 Trans Am's and 43 Formula 455's received the SD-455 engine. The second major coup for the Firebird was the introduction of a new Firebird decal on the Trans Am, which covered almost the entire hood and was quickly nick-named "the screaming chicken," which added to the excitement and popularity of the entire Firebird lineup. Sales of the Firebird and Trans Am were up dramatically, ensuring their survival.

Production: Trans Am:  4,802
                    Formula:    10,166


PONTIAC FORMULA PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Formula 350 ? ? 4,771
Formula 400 ? ? 4,622
Formula 455 227 503 730
Formula 455 SD 10 33 43
---- ---- ---- ----
Total Firebird Formula 237 536 10166 


For the 73 TA SD-455 cars and all 74 SD-455 cars, color and option numbers are not available.
Here are numbers for the 73 Formula SD-455 cars:
33 automatic trans cars: 
cameo white=8
golden olive =1
bucaneer red=1
ascot silver=9
verdant green=1
florentine red=3
valencia gold=1
admiralty blue=5
brewster green=1
navajo orange=1
burma brown=2
10 four-speed cars: 
cameo white=1
bucaneer red=1
ascot silver=1
porcelain blue=1
florentine red=4
admiralty blue=2
Interiors: 
white std=3
black std=5
saddle std=1
white cust=3
black cust=16
saddle cust=7
burgandy cust=7
beige cust cloth=1
Other options: 
N98 Rally II wheels=23
P05 Honeycomb wheels=7
D80 Rear spoiler=15
C08 Cordova top=6
Y99 Handling package=33
V32 Rear bumper guards=7
A31 Power windows=12
AU3 Power door locks=7
C60 Air conditioning=25


*C60 Air conditioning was not available with the M20 4-speed trans
*N41 Power steering and JL2 Power disc brakes were required options with the SD-455


1973 PONTIAC TRANS AM PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
TRANS AM 455 1,420 3,130 4,550
TRANS AM 455 SD     72   180   252
---------------------- ------- ------- -------
Total TRANS AM 1,492 3,310 4,802


Engines:
350 V8 150 bhp.
400 V8 230 bhp @ 4400rpm, 325 lb-ft @ 3200 rpm.
455 V8 250 bhp @ 4000 rpm, 370 lb-ft @ 2800 rpm.
455 (SD) V8 290 bhp @ 4000 rpm, 390 lb-ft @ 3600 rpm.
Performance: N/A

1973 Pontiac Firebird Trans Am 455 CID
Manual Transmission Engine Specifications

Engine Code

WT, WW, ZZ, ZE

Engine RPO

L75

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.0:1

Horsepower @ RPM

250@4000

Torque (Lb/Ft) @ RPM

3700@2800

Head Casting

4X

Carburetor

4-bbl

Carburetor - Federal

7043273

Intake Manifold

497244

Camshaft

Part #

Lift, I/E

.410 / .414

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 289

Overlap - Degrees

54

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

1973 Pontiac Firebird Trans Am 455 CID
Automatic Transmission Engine Specifications

Engine Code

X7, XE, XL, XM, YA, YC, YD

Engine RPOv

L75

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.0:1

Horsepower @ RPM

250@4000

Torque (Lb/Ft) @ RPM

370@2800

Head Casting

4X

Carburetor

4-bbl

Carburetor - Federal

7043262, 7043272

Intake Manifold

497244

Camshaft

Part #

Lift, I/E

.410 / .414

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 289

Overlap - Degrees

54

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor



1973 Pontiac Firebird Trans Am 455 CID Super Duty
Manual Transmission Engine Specifications

Engine Code

ZJ, W8

Engine RPO

LS2

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.4:1

Horsepower @ RPM

290@4000

Torque (Lb/Ft) @ RPM

390@3600

Head Casting

16, 485216

Carburetor

4-bbl

Carburetor

7043273

Intake Manifold

497245, 494405, 495107

Camshaft

Part #

493323

Lift, I/E

.410 / .410

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

301 / 313

Overlap - Degrees

76

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifolds- Right

490802

Exhaust Manifolds- Left

490803

Distributor

   

1973 Pontiac Firebird Trans Am 455 CID Super Duty
Automatic Transmission Engine Specifications

Engine Code

XD, X8

Engine RPO

LS2

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.4:1

Horsepower @ RPM

290@4000

Torque (Lb/Ft) @ RPM

390@3600

Head Casting

16, 485216

Carburetor

4-bbl

Carburetor

7043270

Intake Manifold

497245, 494405, 495107

Camshaft

Part #

493323

Lift, I/E

.410 / .410

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

301 / 313

Overlap - Degrees

76

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifolds- Right

490802

Exhaust Manifolds- Left

490803

Distributor

1974 Pontiac Firebird






Comments: For 1974 gone was the Endura bumper, replaced by new, Federally mandated, fiberglass front end with a slight wedge shape and rubber covered 5 mph bumpers. The chrome rear bumper was also gone, replaced by rubber bumpers. Engine ratings dropped again with the Trans Am's base 400 V8 engine rated at 225 bhp. But for a mere $57, buyers could order the 250 bhp 455 V8, which received a 10 lb-ft boost to 380 lb-ft, but which came only with an automatic transmission. The mighty Super Duty 455 V8 was also available for an additional $578 and were unchanged from the year before. All V8s included true dual exhausts, which made their last appearance on the Firebird. Also available for the last time on the 1974 Firebirds were the Muncie 4-speed manual transmission and the TurboHydramatic 400 automatic transmission. This would also be the last year of the Super Duty engines.

Production: Trans Am: 10,255   -   Super Duty 455: 943
                    Formula:    14,519   -   Super Duty 455: 57

Engines:
350 V8 155bhp.
400 V8 225 bhp @ 4000 rpm, 330 lb-ft @ 2800 rpm.
455 V8 250 bhp @ 4000 rpm, 380 lb-ft @ 2800 rpm.
455 (SD) V8 310 bhp @ 4000 rpm, 390 lb-ft @ 3600 rpm.
Performance:
SD455/310: 1/4 mile in 13.5 seconds @ 104 mph



PONTIAC Firebird PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Firebird Base L6 n/a n/a 7603
Firebird Base V8 n/a n/a 18769
Total Firebird n/a n/a 26372
Total Firebird Esprit n/a n/a 22583
Formula 350,400,455 n/a n/a n/a
Formula SD 455 n/a n/a 57
Total Firebird Formula n/a n/a 14519
Trans Am 400 1750 2914 4664
Trans Am 455 - 4648 4648
Trans Am SD 455 212 731 943
Total Trans Am 1962 8393 10255
Grand Total - - 73729

PONTIAC SD-455 ENGINE PRODUCTION FIGURES
MODEL 4-SPEED AUTOMATIC TOTAL
1973 Firebird Trans Am 72 180 252
1973 Firebird Formula 10 33 43
1974 Firebird Trans Am 212 731 943
1974 Firebird Formula n/a n/a 57
TOTAL n/a n/a 1,295

  1. Figures obtained from official Pontiac Historical Society figures.
  2. In 1973, 4,802 Firebird Trans Ams were produced.
  3. In 1974, 10,255 Firebird Trans Ams were produced.
  4. For complete production figures for 1973 and 1974 Pontiac Firebirds .

1973-74 PONTIAC FIREBIRD TOTAL PRODUCTION FIGURES
YEAR Firebird Esprit Formula Trans Am Total
1973 14,096 17,249 10,166 4,802 46,313
1974 26,372 22,583 14,519 10,255 73,729

  1. Figures obtained from official Pontiac Historical Society figures.



1974 Pontiac Firebird Trans Am 400 CID
Manual Transmission Engine Specifications

Engine Code

WT, WW, ZZ, ZE

Engine RPO

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

8.0:1

Horsepower @ RPM

225@4000

Torque (Lb/Ft) @ RPM

330@2800

Head Casting

4X

Carburetor

4-bbl

Carburetor - Federal

7043263

Intake Manifold

495106

Camshaft

Part #

9779067

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 289

Overlap - Degrees

55

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

   

1974 Pontiac Firebird Trans Am 400 CID
Automatic Transmission Engine Specifications

Engine Code

X7, XE, XL, XM, YA, YC, YD

Engine RPO

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

8.0:1

Horsepower @ RPM

225@4000

Torque (Lb/Ft) @ RPM

330@2800

Head Casting

4X

Carburetor

4-bbl

Carburetor - Federal

7044263, 7044266,7043263, 7043266

Intake Manifold

495106

Camshaft

Part #

9779066

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 282

Overlap - Degrees

55

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor



1974 Pontiac Firebird Trans Am 455 CID
Automatic Transmission Engine Specifications

Engine Code

AU, A4, YW, YY, Y9, ZU, ZW, Z4

Engine RPO

L75

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.0:1

Horsepower @ RPM

250@4000

Torque (Lb/Ft) @ RPM

380@2800

Head Casting

4X

Carburetor

4-bbl

Carburetor - Federal

7044262

Carburetor - High Altitude

7044272

Intake Manifold

495106

Camshaft

Part #

9779067

Lift, I/E

.410 / .414

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 289

Overlap - Degrees

54

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor


1974 Pontiac Firebird Trans Am 455 CID Super Duty
Manual Transmission Engine Specifications

Engine Code

W8

Engine RPO

LS2

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.3:1

Horsepower @ RPM

290@4000

Torque (Lb/Ft) @ RPM

395@3200

Head Casting

16

Carburetor

4-bbl

Carburetor

7044273

Intake Manifold

495107

Camshaft

Part #

493323

Lift, I/E

.410 / .410

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

301 / 313

Overlap - Degrees

76

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifold - Right

490802

Exhaust Manifold - Left

490803

Distributor

   

1974 Pontiac Firebird Trans Am 455 CID Super Duty
Automatic Transmission Engine Specifications

Engine Code

Y8

Engine RPO

LS2

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

8.3:1

Horsepower @ RPM

290@4000

Torque (Lb/Ft) @ RPM

395@3200

Head Casting

16

Carburetor

4-bbl

Carburetor

7044270

Intake Manifold

495107

Camshaft

Part #

493323

Lift, I/E

.410 / .410

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

301 / 313

Overlap - Degrees

76

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Exhaust Manifold - Right

490802

Exhaust Manifold - Left

490803

Distributor



1975 Pontiac Firebird






Comments: In what had been a sea of pony car competitors, the Pontiac Firebird was all alone for 1975. The Camaro Z28, AMC Javelin, Plymouth Barracuda, and Dodge Challenger all were discontinued. The Ford Mustang was now offered on a Pinto platform and boasted a top engine offering of a 105 bhp 2.8 liter V6! The 1975 Firebird featured a new front end (it's third in three years) and a much improved rear window, which greatly improved visibility. The instrument panel stayed the same, but the old 160 mph speedometer was replaced by a new 100 mph unit, to better reflect the new times. The base 400 cid V8 Trans Am engine put out a pitiful 185 bhp, but still cranked out 310 lb-ft of torque. But the big news was what was lost: No Super Duty 455 engine, no Turbo-Hydramatic 400 automatic transmission, no Muncie Four-Speed Manual Transmission, no true dual exhausts. The main culprit: the new Federally mandated Catalytic Converters. The 455 V8 was re-introduced mid-year in "H.O." guise, but it was just the 455 engine from the Bonneville and produced only 200 bhp.

Production: Trans Am: 27,274
                    Formula:   13,670

PONTIAC Firebird PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Total Base Firebird n/a n/a 22,293
Total Firebird Esprit n/a n/a 20,826
Total Firebird Formula n/a n/a 13,670
Trans Am 400 6,140 20.277 26,417
Trans Am 455 857 - 857
Total Trans Am 6,997 20,277 27,274
Grand Total - - 84,063

Engines:
350 V8 155bhp.
400 V8 185 bhp, 310 lb-ft.
455 V8 200 bhp @ 3800 rpm, 330 lb-ft @ 2000 rpm.
455 (HO) V8 200 bhp.
Performance:
455/200: 1/4 mile in 16.1 seconds @ 89 mph



1975 Pontiac Firebird Trans Am 400 CID
Manual Transmission Engine Specifications

Engine Code

WT

Engine RPO

L78

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

7.6:1

Horsepower @ RPM

185@3600

Torque (Lb/Ft) @ RPM

310@1600

Head Casting

5C

Carburetor

4-bbl

Carburetor - Federal

7045263

   

Intake Manifold

495106

Camshaft

Part #

9779066

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 283

Overlap - Degrees

59

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

   

1975 Pontiac Firebird Trans Am 400 CID
Automatic Transmission Engine Specifications

Engine Code

YS

Engine RPO

L78

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

7.6:1

Horsepower @ RPM

185@3600

Torque (Lb/Ft) @ RPM

310@1600

Head Casting

5C

Carburetor

4-bbl

Carburetor - Federal

7045274

Carburetor - California

7045564

Intake Manifold

495106

Camshaft

Part #

9779066

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 283

Overlap - Degrees

54

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor



1975 Pontiac Firebird Trans Am 455 CID
Manual Transmission Engine Specifications

Engine Code

WX

Engine RPO

L75

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

7.6:1

Horsepower @ RPM

200@3500

Torque (Lb/Ft) @ RPM

330@2000

Head Casting

495351, 5C

Carburetor

4-bbl

Carburetor - Federal

NA

Intake Manifold

496140

Camshaft

Part #

9779067

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 289

Overlap - Degrees

54

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor



1976 Pontiac Firebird






Comments: 1976 would be the last year of the 455 engine, and the first year of available T-Tops. All Firebirds received new more angular bumpers which improved their appearance, and Pontiac introduced the very popular Black-and-Gold Special Edition Trans Am which quickly became one of the most famous Trans Am's of all time.
The Limited Edition Trans Am was introduced in February at the Chicago Automobile Show. The LE Trans Am had Starlight black finish with gold striping, along with gold interior accents,gold honeycomb wheels, a 50th anniversary badge,plus more, including T-Tops. The cars were shipped to Hurst Corp. in Michigan. But due to problems with the Hurst roof treatment only about 25 % of the LE cars had T-Tops. The total production was only 2590 with only 643 LE Trans Am's having the T-Tops. The installation of the optional 455 was less than 500 for the LE Trans Ams, only 110 455 engined LE Trans Am with T-Tops were made.
This would be the first year that over 100,000 Firebirds were sold.

PONTIAC FIREBIRD PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Total Firebird Base n/a n/a 21,206
Total Firebird Esprit n/a n/a 22,252
Total Firebird Formula n/a n/a 20,613
Trans Am 400 5,424 31,591 37,015
Trans Am 455 7,099   7,099
Limited Edition Trans Am      
Coupe 400 (Y81)     1,628
Coupe 455 (Y81) 319   319
T-Top 400 (Y82)     533
T-Top 455 (Y82) 110   110
Total Trans Am     46,704
       
Grand Total -  -  110,775

Engines: 350 V8 155bhp.
400 V8 185 bhp, 310 lb-ft.
455 (HO) V8 200 bhp @ 3800 rpm, 330 lb-ft @ 2000 rpm.
Performance:

1976 Pontiac Firebird Trans Am 400 CID
Manual Transmission Engine Specifications

Engine Code

Engine RPO

L78

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

7.6:1

Horsepower @ RPM

185@3600

Torque (Lb/Ft) @ RPM

310@1600

Head Casting

6X

Carburetor

4-bbl

Carburetor - Federal

7043273

Camshaft

Part #

9779066

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 283

Overlap - Degrees

55

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

   

1976 Pontiac Firebird Trans Am 400 CID
Automatic Transmission Engine Specifications

Engine Code

Engine RPO

L75

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

7.6:1

Horsepower @ RPM

185@3600

Torque (Lb/Ft) @ RPM

310@1600

Head Casting

6X

Carburetor

4-bbl

Carburetor - Federal

7043262, 7043272

Camshaft

Part #

9779066

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 283

Overlap - Degrees

55

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor


1976 Pontiac Firebird Trans Am 455 CID H.O.
Manual Transmission Engine Specifications

Engine Code

Y3, Y4, Y8, Z3, Z4, Z6

Engine RPO

L75

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

7.6:1

Horsepower @ RPM

200@4000

Torque (Lb/Ft) @ RPM

330@2800

Head Casting

6X

Carburetor

4-bbl

Carburetor - Federal

7043273

Camshaft

Part #

9779067

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 289

Overlap - Degrees

54

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

   

1976 Pontiac Firebird Trans Am 455 CID HO
Automatic Transmission Engine Specifications

Engine Code

WX

Engine RPO

L75

Displacement

455 CID

Bore x Stroke

4.1522" x 4.121"

Compression Ratio

7.6:1

Horsepower @ RPM

200@3600

Torque (Lb/Ft) @ RPM

330@2800

Head Casting

6X or 6H

Carburetor

4-bbl

Carburetor - Federal

7043262, 7043272

Camshaft

Part #

9779067

Lift, I/E

.407 / .407

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

273 / 289

Overlap - Degrees

NA

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.77"

Distributor



1977 Pontiac Firebird






Comments: 1977 saw a new "Batmobile" front end with quad square headlamps and ever more complex engine choices. The Chevy inline six was dumped for a Buick 231 cubic inch (3.8 liter) V6 as the base engine. A new 301 (4.9 liter) V8 rated at just 135 bhp was available in Esprits and Formulas, with the familiar 350 was optional. Trans Am's featured either a Oldsmobile 403 (6.6 liter) V8 or the Pontiac 400 (T/A 6.6) engine under their shaker hood. Meanwhile, Firebirds sold in California had to make due with Chevy 305 and 350 V8s to meet the state's strict emission laws. But 1977 would the year that firmly established the Firebird as the performance car of the 1970s. Burt Reynolds drove a Black-and-Gold Special Edition Trans Am in the unexpected movie hit "Smokey and the Bandit", that drove the Firebird's popularity (and sales) to new heights.



1977 PONTIAC FORMULA/TA W72 PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Base Trans Am (W72) 8,319 10,466 18,785
Trans Am Y81 (W72)   384   549   933
Trans Am Y82 (W72) 2,699 3,760 6,459
Formula (W72) 1,735   756 2,491
------------- ----------- ----------- -----------
Total W72 TRANS AM/FORMULA 13,137 15,531 28,668
       


1977 PONTIAC FIREBIRD PRODUCTION FIGURES
MODEL MANUAL AUTOMATIC TOTAL
Firebird base V6,V8 ? ? 30,642
Esprit V6,V8 ? ? 34,548
       
Formula ? ? 19,310
Formula 400 (W72) 1,735 756 2,491
------------- ----------- ----------- -----------
Total Formula ? ? 21,801
       
Trans Am 400 (L78)   29,313 29,313
Trans Am 400 (W72) 8,319 10,466 18,785
Trans Am 403 (L80)   5,079 5,079
SE 400 L78   748 748
SE 400 L78 w/T-Top   6,030 6,030
SE 400 W72 384 549 933
SE 400 W72 w/T-Top 2,699 3,760 6,459
SE 403 (L80)   180 180
SE 403 (L80) w/T-Top   1,217 1,217
------------- ----------- ----------- -----------
Total TRANS AM 11,402 57,342 68,744
       
TOTAL FIREBIRD     155,735


Engines:
231 V6 105 bhp.
301 V8 135 bhp.
305 V8 (California).
350 V8 (California).
350 V8 155bhp.
400 V8 185 bhp, 310 lb-ft. 403 V8.
Performance:
400/185: 1/4 mile in 16.02 sec. @ 89.64 mph.

1977 Pontiac Firebird Trans Am 400 CID
Automatic Transmission Engine Specifications

Engine Code

XA

Engine RPO

L78

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

7.6:1

Horsepower @ RPM

180@3600

Torque (Lb/Ft) @ RPM

325@1600

Head Casting

6X

Carburetor

4-bbl

Carburetor - Federal

17057274

   

Intake Manifold

525355

Camshaft

Part #

527471

Lift, I/E

/

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

NA / NA

Overlap - Degrees

NA

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

1103269 w/2.92 & under axle ratio

Distributor

1103271 w/2.93 & higher axle ratio

    

1977 Pontiac Firebird Trans Am 403 CID (Oldsmobile)
Automatic Transmission Engine Specifications

Engine Code

U2, U3, VA, VB

Engine RPO

L80

Displacement

403 CID

Bore x Stroke

4.3512" x 3.385"

Compression Ratio

8.0:1

Horsepower @ RPM

185@3600

Torque (Lb/Ft) @ RPM

320@2200

Head Casting

554717

Carburetor

4-bbl

Carburetor - California

17057550 w/o Air Cond

Carburetor - California

17057553 w/ Air Conditioning

Carburetor - High Altitude

17057258

Intake Manifold

411990

Camshaft

Part #

562299

Lift, I/E

.440 / .440

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

NA / NA

Overlap - Degrees

NA

Intake Valve Dia -

2.00"

Exhaust Valve - Dia

1.50"

Distributor


1977 Pontiac Firebird Trans Am 400 CID T/A 6.6
Manual Transmission Engine Specifications

Engine Code

WA

Engine RPO

L78 / W72

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

8.1:1

Horsepower @ RPM

200@4000

Torque (Lb/Ft) @ RPM

330@2800

Head Casting

6X

Carburetor

4-bbl

Carburetor - Federal

7053263

Intake Manifold

525355

Camshaft

Part #

526793

Lift, I/E

NA / NA

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

NA / NA

Overlap - Degrees

NA

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor

   

1977 Pontiac Firebird Trans Am 400 CID T/A 6.6
Automatic Transmission Engine Specifications

Engine Code

Y6

Engine RPO

L78 / W72

Displacement

400 CID

Bore x Stroke

4.1212" x 3.750"

Compression Ratio

8.1:1

Horsepower @ RPM

200@4000

Torque (Lb/Ft) @ RPM

330@2800

Head Casting

6X

Carburetor

4-bbl

Carburetor - Federal

17057266

Intake Manifold

525355

Camshaft

Part #

527471

Lift, I/E

NA / NA

Rocker Arm Ratio

1.5:1

Duration I/E - Degrees

NA / NA

Overlap - Degrees

NA

Intake Valve Dia -

2.11"

Exhaust Valve - Dia

1.66"

Distributor


1978 Pontiac Firebird






Comments: Attempting to capitalize on its new found popularity, Pontiac offered a slew of Special Edition Firebirds including a Gold Trans Am with brown accents and Blue "Sky Bird" and Red "Red Bird" Firebirds. Sales soared to a record 187,294 units, including 93,341 Trans Am's.

Production:
Total Firbirds: 187,285
                    Trans Am: 93,341
                    Formula:   24,346
                                        810 W72 Formulas with 4-speed transmissions

Engines:
231 V6 105 bhp.
301 V8 135 bhp.
305 V8 (California).
350 V8 (California).<