Want to grab one of the last great factory muscle cars of the original era? This 1971 Pontiac Trans Am 455 HO might be your next project. You can see it here on ebay, where it has a somewhat surprising 35 bids, notching in at over $15K, with several days to go. If you’re intrigued, there is no reserve mentioned, so bid a number you could live with. You’ll then need to get to La Fayette, GA, where the seller will be waiting for you with a clean title in hand.
What will you have taken on? A car that will look amazingly sinister when finished, but which needs love in every inch of its sheet metal. Two things you’ll want to address right away are the state of the engine and the transmission. The car, as is indicated by its model name, should have a 455 CID mill, and indeed it does, but from a 1973 birthdate. You do get a date-coded block with the deal to fix up and install. The transmission is currently a Doug Nash five-speed stick, which might be fun if functional, but the original gear-switcher was automatic, so you’ll have to decide whether you want excitement or correctness in this area. Mechanically, the car is said to run and drive, but to be in need of some brake work.
The body, also, needs some attention. There are rusty spots that range from curious cancer above the passenger window to fender rot-through in the lower extremities. The trunk floor also shows the results of water sitting under the mat, and the rear seating area has some suspicious carpeting that appears to have been wet. Still, shots of the undercarriage are mostly hopeful, so you’re going to do some bead blasting, or whatever method of stripping you prefer, but you likely won’t be left holding dust and hoping the body stays together. Inside the car, things look extremely tidy other that what was just mentioned.
This once-proud 1970s muscle car was one of the last of its generation to carry the banner for factory grunt, existing on the cusp of the time when it would be decades until its like was seen again. The horsepower rating looks a bit tame now, at 335 for the original HO configuration, but for the day, with its limited electronics and fuel delivery possibilities, it was a screamer. Are you the one to put this pony car back to right and thrash it down the road on a summer’s evening?
Run hard and put away wet. Wasn’t this super duty h.o 455 motor a hand built performance number from Pontiac ?
Thanks Brian. 🏁
The Super Duty and HO’s are different engines. The HO’s were used in 1971 and 1972, the Super Duty 1973 and 1974. The Super Duty had upgrades to the block and rods, there were relatively minor other changes too. Both used round port heads.
One thing to keep in mind, Pontiac recycled the 455HO name on some later engines used in Trans Ams, but they a shadow of the 1971/1972 engines by that point in time.
Steve R
The 73-74 Super Duty’s were hand assembled, the earlier H.O.’s were not.
Other than having the same bore and stroke as the 455 H.O., not much else was shared between the two engines. The SD’s had a unique block, crank, forged pistons, forged rods, and their own round port heads with different intake and exhaust ports that breathed better than the H.O. and Ram Air IV versions.
I had ordered a Cosworth Vega in 74, but when production of the 74 version was cancelled, I went looking for something else. I tried to find a Super Duty, but ended up with a 400 4 speed TA instead. Surprisingly, considering there were only about 940 74 Super Duty’s made, three of them were withing 10-15 miles of me in South Jersey. I was friends with the owner of a white with saddle interior automatic SD, knew the owner of a red with black interior 4 speed one and the son of a local Pontiac dealer had a loaded with every option blue with white interior automatic one. I had a few rides in my friends white one and the difference in performance over my 400 4 speed was noticeable.
That explains why, when I went to the dealer in October of ’73 to order my ’74 Formula SD with every option, they told me it would take AT LEAST six months before it would come in !!! ( I settled on a 400 and after the warranty expired, I had it “worked on” )
You’re so lucky you didn’t get a Vega!
The only thing that matters on this car is whether it has the original HO heads. What head code is the first question to be asked.
Missing heads, intake, carb, exhaust manifolds, rims, etc. Really affects value.
This car has been scavenged of all its original parts.Might as well build it anyway you would like. This is my favorite body style Firebird. Had a white one come in special ordered by the customer. It had the decal delete option. It was gorgeous!
A lot of work here. To bad the original rims are gone. To bad it was converted to a manual. I like manual shift cars. It just seems like a lot of work for the conversion.
I wouldn’t get too worked up over this “455 HO” cause that ain’t what is is now. The motor in it could be out of a station wagon. This is one of the best body styles ever on a Firebird and the 5 speed is a big plus, but in the end it is just a rough Firebird.
Sold on 8/19/2025 for a high bid of $27,100.
Steve R
$18k would be a stretch with everything that everyone’s, stated. Otherwise, even the canvas needs a lot of patching up before anything else looking to correct.
Absolutely insane.
The price is ridiculous for this car.
I completely agree!