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1970s Pontiac Trans Am - Gold Chains To Glory

They Might Be Disco, But We Still Dig 'Em. The Hero Trans Ams Of '76-'81 Take Us From

Photography by , Primedia Archives

Mandrel-bent, large-diameter exhaust tubing will outflow crush-bent muffler shop pipes, and the aftermarket offers multiple kits for second-gen F-cars from sources like Torque Tech and Flowmaster, which actually offers several types of kits, including one that uses a transverse muffler behind the axle for extra ground clearance.

More info:Car Sound/Magnaflow Exhaust SystemsRancho Santa Margarita, CA800/

FlowmasterSanta Rosa, CA800/

Hedman HeddersWhittier, CA562/

Hooker (A Division of Holley)Bowling Green, KY270/

Random TechnologyLoganville, GA30052; 770/

Ram Air RestorationDallas, TX800/

Torque Tech Performance Exhaust;Valdosta, GA888/

1980The '79 restyle carried over to the '80, save for minor changes to graphics, most notably, smaller Trans Am callouts on the rear spoiler and the front fenders. The major change saddened hard-core motorheads: The 6.6 was dead. Not even the low-compression Olds motor could be had, and Pontiac's substitute for inches was a turbocharged 4.9L. Turbocharging was exotic stuff back in 1980, and Pontiac's advertising hyped the new powerplant big time, attempting to convince consumers that this modern approach to power was far superior to the antiquated big-inch V-8. Subsequent magazine testing indicated otherwise. No '80 Trans Am could be ordered with a four-speed trans, and California non-turbo cars got 305 Chevys. The turbo-styled wheels first seen on the '79 Anniversary model were obviously designed with the turbo car in mind, but the 15x8 snowflakes were still available on non-turbo WS-6 cars. Standard Trans Ams could be had with 15x7 snowflakes or the old stand-by Rally II steel wheels.

Cylinder HeadsThe period of Trans Ams we're covering all suffered from low compression, but the good news is you can correct the situation without having to completely rebuild your engine. With the exception of the late-'70s low-deck 265/301 engines, all '65-'79 Pontiac V-8s are based on the same block-there is no big- or small-block. Also, Pontiac used the combustion chambers in the cylinder heads to set compression ratio, so nearly all of the low-compression versions retained flat-top pistons. That means swapping heads to castings with smaller chambers will get the compression up. For example, a '76 TA with the optional 455 left the factory with 7.6:1 compression thanks to huge 124cc combustion chambers. Swapping the original No. 6H heads for a set of early '70s 400 heads with 96cc chambers-specifically, No. 96 from a '71 and No. 7K3 from a '72-will bring compression into the desirable mid-9.0:1 range. The heads themselves are fairly similar in port volume and arrangement, and only the exhaust valve size is different (1.77 inch for the earlier head, 1.66 for the late). This increase in compression will have a significant impact on performance yet will remain nearly undetectable to all but hard-core Pontiac aficionados. A good valve job and some port work are worth the effort as well.

Of course, today there are also aftermarket heads, and Edelbrock's aluminum Performer RPM assemblies are modeled after the vaunted Pontiac Ram Air IV castings, but with contemporary improvements, and they're even smog-legal through the '79 model year. Kauffman Racing also offers aluminum Pontiac heads, configured with the traditional D-port exhaust arrangement. With aluminum heads, compression should be raised a little further to compensate for the faster rate of heat dissipation-10.0:1 is a good goal.

More info:Edelbrock; Torrance, CA310/

Kauffman Racing EquipmentGlenmont, OH740/

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