1973 Pontiac Firebird Formula 455-SD

[Paul Ceasrine]

Original Plans for the 1973 SD-455

* Camshaft #041 = .470"/.470" Lift ~ 308*/320* Duration ~ 87* Overlap

* Aluminum Intake Manifold

* Solenoid Activated Vent-Slot Opening for Hood Scoop

Though EPA Emission Restrictions wouldn't permit it, but with the desired
10.25 - 1 Compression Ratio the 1973 SD-455 could put out 370 HP.

[chris ok]

I know it's not an SD but my neighbor recently sold their 73 455 4 speed Trans Am. It sat in street last 2 years thru rain, snow, salt etc... after a nother neighbor painted it 5 or 6 years earlier. I inquired if it is for sale, 10k, to much for me as it needed to be restored again.
Left my neighborhood and I miss driving by it. Only saw it drive 2x in those almost 10 years it sat near my house.
Chris

[Paul Ceasrine]

One of the few still around.

[Rich Biebel]

Was the flared front fender/lower valance bodywork an option or part of a certian model package?

I like the cars better without it....a cleaner look.

Herslows has it in the SSDI cover picture so maybe it was std with the SD's ???

I worked on many later model T/A's.....during the "corporate engine" era...

Lots of black ones with t-tops and honeycomb wheels.... Smokey and the Bandit.....

In '79 I believe it was a manual trans TA came with a 403 Olds motor and a Turbo 400 came with a Pontiac 400.......

The engines installed during that period triggered a firestorm and class action lawsuit......Buyers were not happy to learn they bought a Pontiac and did not get a Pontiac engine.....Soon after that the window stickers on new cars stated clearly that engines from various brands were being used and also the mileage stats were on there....

Carbs were calibrated way to lean.....and we dealt with driveability issues and mileage complaints every day......

Many people blocked off the EGR valves thinking it would make their car run better.....It made it worse and pinging was a major issue....

[GTX JOHN]

You are right on the timeframe.
The 79 Olds 403 combo ran a terrible 17 Sec. ET.

[Paul Ceasrine]

Rich,

The 1973 Trans Am cars had the 'gaudy' Front Spoiler, and Front and Rear front-flared Wheel Wells, besides that 'funky' Bird hood decal.

The Formula 455 and Formula SD-455 cars had the cleaner looking front valance {fiberglass} with a small air-dam spoiler, all as one-piece.

As seen in the photo {Post #28}.

On all the EGR and Smog connections,,,,,,,,,, my father pulled all that stuff off, and disconnected the Air Conditioning Pump, and
removed it., replaced the Cast-Iron Intake with an Edelbrock Spead-Bore Intake, and played around with the 800 CFM Rochester carburetor..

Once the SD-455 Engine got warm, it was like somebody filled the gas tank with 'Jet Fuel'..........

[Dwight Southerland]

Originally Posted by Rich Biebel

In '79 I believe it was a manual trans TA came with a 403 Olds motor and a Turbo 400 came with a Pontiac 400.......

The 403 Olds was used 1977-1979 in the Firebird and was available with automatic only. In 77 & 78 there was a 400 Pontiac engine available rated at 180 hp. In 78 & 79 a 400 "HO" Pontiac engine was available rated at 220 hp and available with a 4-speed only.

[Rich Biebel]

Well I was close on the trans and engine combos....

To be honest those cars were really not good...

Many had T-Tops and they usually leaked.....The doors were huge and the cars had squeaks and rattles and were constantly brought in for these issues....

The T/A's were about the only muscle car left by then and fun to drive....

I liked the shaker hood and the big decal on there....

[Paul Ceasrine]

A Formula SD-455 with the 'rare' Option {Code #D98} ''Stripe Kit'

Which I believe was supplied by the ''Factory' and installed by 'Dealer'.