The Pontiac Super Duty 455 Story

The Pontiac Super Duty 455 was unique in several ways. This video will give a bit of insight into what makes it special. The background music is Funkytown by Lipps Inc. The Engine Block & Component Photos Are The Property Of Jim Dietzler/HPP.

[@trucking604]

The only American car company that made a true muscle car engine in 1973-74! Pontiac always dared to be different!

[@stevejohnson1397]

After 1970 all the Pontiac became boat anchors because the combustion Chambers in the cylinder heads or increase from 64 CC to 110 cc lowering the compression ratio from 10 to 1 to 8to1the super duty 455 I had a little bit higher compression ratio of 8.4 an a different crankshaft nothing special just a boat anchor

[@quincee3376]

@@stevejohnson1397 lol...hell no. 73's move . Not a boat anchor at all. 74 were meh and 75 and newer were a total joke but the 73 moves. My buddy has one.

[@jeremythompson9122]

@@stevejohnson1397 Lol a 455 Super Duty engine is anything but a boat anchor. It's basically a full race engine de-tuned to run on the street. A regular low compression 455 is a boat anchor. The 455SD had practically nothing in common with a regular 455 other than the displacement. 13.5 seconds in the 1/4 mile isn't what id call a boat anchor. Not even close

[@harryguy76]

@@jeremythompson9122 All those engines...even the Hemi is a boat anchor compared to todays engines...with near half the weight...double the fuel efficiency and way more reliable... Muscle cars are not dead...they are the best they have ever been...especially when one throws a modern light weight efficient engine into an old classic...like an aluminum 5.3 stroked to 427 cid weighing 400 lbs dressed making 500hp and tq easy on pump gas with hyd cam...in something like a 67 Mustang fast back...which is just wrong and only an example lol... I kick myself in the ass for trading my 78 Pontiac Sunbird Formula coupe for a truck...it had a 350 boat anchor err truck motor in it with 4 barrel ,headers and dual exhaust...nothing special and went pretty fast for what it was...faster and handled better then any old Firebird of the same vintage...but it would have been crazy with an aluminum 5.3 swapped into it...not just for the stock 350 hp...but more so for the 200 lbs weight savings off the front end of the car would have been a huge improvement in speed, braking and handling... I cringe every time I think about getting rid of it...the thing was mint....nowadays you never see them any more....most people never heard of them and think of a front wheel drive 4 banger POS...not a mini Firebird.....damn it.

[@hksigman]

The music is too loud!!

[@johndunn678]

Funky town needs to be turned down most definitely

[@bobwilson758]

Un watchable - Shit

[@trucking604]

Pontiac invented the muscle car, and ended the muscle car.

[@MasterChief-sl9ro]

Nobody ended shit.. The EPA to my generation was if it takes away HP. It fucking gets tossed! As you always had a friend at the inspection station. As I almost got caught. Just as I was still on the rack. The fucking trooper shows up to collect his books. I had to idle out of the shop before he could hear that exhaust and lopping cam! As that salvage yard was your friend and it was full of Muscle car engines! Man those were the days....

[@jeremythompson9122]

The EPA ended muscle cars...not Pontiac. Chrysler built the first ever muscle car...the 55 Chrysler 300. And Dodge, Plymouth, and Desoto started building their own high performance models in 1956...the Dodge D-500, Plymouth Fury, and DeSoto Adventurer. Mopar invented muscle cars...not Pontiac. Even Jim Wangers himself wrote that in his memoirs. But Pontiac did build the car that started the full blown muscle car craze...the 64 GTO. And Pontiac did build the last true muscle car as well...the 74 Trans Am/Formula Firebird 455SD. I'm a Mopar guy but Pontiac has always been my favorite GM division and my favorite high performance car manufacturer other than Dodge and Plymouth

[@joshbrekke6374]

Actually ford built the first muscle car for the masses with the flat head V8 1932 coupe. But Duesenberg should get the credit, also for antilock brakes back in 1929

[@trucking604]

The EPA did end the Muscle Car era. In 1972 the automobile manufacturer's had to drop the compression to run on low lead and no lead gasoline then in 1973 they started with EGR and the other pollution goodies, so ending the muscle car era. Pontiac was the only American car company to build a true muscle car engine in 1973 and 1974 and yet still meet the emission standards of the day with the 455 SD. Not an easy feat.

[@chrisholcombe137]

GM started and pushed for mandatory unleaded fuel Feb. 1970 and wasn't completed till 1974 ! Thanks GM had bad ass 427 rats on premium fuel in 1969 then pushed for little trap doors on your fuel tank for a unleaded future ?

[@dannywilsher4165]

I love these kinds of videos!!! We all have our stories of the ones that got away. I also had a white 73 HD 455 Trans Am. Sickness overwhelms me thinking about me selling it. I loved that car!!!!!! I bought a 77 after I sold the 73 thinking I would build me one even better. I built a 455 with all the best parts made back then. Ram Air IV heads, hooker headers, all the goodies. And it did run much better than the SD. I was out of town on vacation and my younger brother needed partying money and sold my 77 Trans Am!!! I think I should get all the guys commenting that they were going to beat that guy up for parting out that 74 and come beat me up for selling my 73! And my brother for selling my 77... I had a 69 Grand Prix model SJ that had a 428 that was a pretty awesome car also....

[@kingkrimson8771]

The SD-455 also found its way into a small number of Formula Firebirds. Those are the ones to have if you're looking for ultimate rarity.

[@clevlandblock]

Dirty little secret. Unlike the TA, posi wasn't standard on the Formulas. There are some SD Formulas with open rear ends.

[@74SD455TA]

In fact probably most of them didn't have a posi.....PLUS, you might even see a 2.56 axles and not even a 2.76. You had to be real careful when spec'ing out an SD Formula. An that wasn't good enough either, the salesman had no info either!! One of the best ones is that on both the TransAm and the formula, if you ordered an automatic and did not order a center counsole, you ended up with a column shift car!, @@clevlandblock

[@timjones5844]

That's lofty RPM's for a long stroke engine like this. This thing must have been built tough.

[@Banjo455]

Thanks Bandit!! The SD is just one of many great engines out there and I love em all...especially the Ponchos!!

[@bartbullock9742]

Yo Banjo, I am senior citizen, I remember my Pontiac buddy when I was young ,mid to late '70s, he had what I thought was 455 sd, I was told it came with a stage 2 Cam that had to be ordered(from factory) this motor, (several of his friends built the same motor, from junkyard, armed with the right part number for the cam) had factory exhaust manifolds,(everything factory), it made 510 horsepowe, 570 ft lb of torque, on Dyno. I am curious what you know about this.... Remember, all factory motor.

[@keachmister]

I have a 455 that was given to me. It's '73 block (no, not sd). When sent to the machinist for rebuild, he found what you mentioned. A broken lifter bore. He was able to sleeve it, and worked out great. We went with weaker springs than originally planned. Running like a true torque monster now years later, but always have that thought about lifter bores. Hope they hold up. BTW, 73-74 were my late HS years. Wish I new all this SD stuff then. Would've saved up for one ...or 2,3. Good vid Banjo.

[@Steveeoaktree41]

Excellent! Thanks for the upload, all of us Ponchanatics appreciate it.

[@bobburchett8517]

My Brother in Kentucky just passed away 3 days ago. He was 70 years old and in poor health. I live in El Paso, Tx and I went to Kentucky 2 years ago because my Brother gave me a 1970 Pontiac Firebird with a 350 cu. in. High Performance Engine. He called me about a month before he passed away and said he had a 455 cu. in. Engine and a 4 speed Top Loader Transmission that he was giving me to go in the Firebird. I can't wait to go to Kentucky in a couple of weeks to pick up my new toys. God bless my dear departed Brother. Oh if you only knew some of the stories that my Brother and I have from our younger days.

[@sergiojacquez2277]

Sorry for your loss. R.I.P. 🙏 Enjoy the Bird.... By the way, I have lots of family in El Paso. Around Loma Land area...

[@robertbairt9094]

Could be a 350HO/320hp in 68✌️

[@mattwolice9741]

Nice overview, well done... from what I could hear. Geeze turn down that damn awful music.

[@smartalecthemotorguy2405]

I have a 72' 455 HO and you just let me know every thing I'm missing out on!

[@superduty4556]

Sorry about your cast rods! Haha

[@six-pack1332]

My friend had a 73 Grand Prix SSJ that had a SD-455. I've been called a liar but, it's true. This car was ungodly fast! It had vinyl top, leather interior and, a suspension that had it sitting approximately 3 inches higher all the way around. The suspension was firm but. smooth like a cop car suspension. I've owned and been in many fast cars. This one was in a league of its own. I estimate it topped out at 160 mph. I'm not sure if it was a special order car or what. I miss that car. We had much fun just obliterating cars in street races. I drove it quite frequently and loved every second of it! Great power, great brakes, great handling and, comfortable as hell! That's all I got, thanks for reading this rambling account of my friends car.

[@chutoparadinni5474]

If he did, it was a Swapped or something like it, maybe dealer installed, non from the Factory

[@six-pack1332]

@@chutoparadinni5474 Maybe so. Everything looked factory but, who knows? I wish everyone could experience a car like that once in their life. Words don't do it justice. He bought it off of a used car lot I worked at. Who knew?

[@clevlandblock]

Well if you look at an original Pontiac customer brochure for the 1973 model year, they do show the SD-455 as an option for the GP. It was also listed as an option for the GTO and Grand Am. It could be a prototype or pilot car that got into public hands.

[@keithbaker1951]

well.. the music totally ruined the video.. very interesting info with a too loud horrible soundtrack

[@MrColdwatercanyon]

Keith Baker I get the period song but yes i have to agree

[@gfoursux9]

Agreed. I was trying to listen to wha he was saying but kept losing track.

[@MrColdwatercanyon]

Waterbird 4222 this guy should make a revised vid think he still has the Bird ?

[@cdnpro4x577]

I quit watching a quarter of the way in because of it.

[@toneyfast1582]

Whats up with music

[@05cr125rider]

Hey Banjo455,real pontiac OLD guy here! Love your TA my friend. Had a 71 455 HO TA a few years ago and still have my "survivor" '68 4 spd HO GTOI've had since 1980.Thanks for your video.Hey,do you remember when Hot Rod magazine compared the '73 SD455 TA to the Pantera and the title of the story was,"AT half the price the Trans Am is twice the car" ????!!!!

[@rickyburton4642]

I remember them, and they still are great 👍!😃👍👍🇺🇸🇺🇸🇺🇸

[@scottbaker1800]

Had lots of fun with my 66 GTO hiding a 73 SD 455.... 18 mpg till I opened up the the front and back carbs

[@judgegixxer]

So cool, thank you for posting. Love pontiacs, they had a few other potent sleeper motors that kinda flew under the radar. Crafty bunch at pmd. Congrats on keeping your beauty car so long.

[@VirginianSpencer]

I ordered an SD-455 in 1973, but what got delivered was a "standard" 455. I took it and was very disappointed it was way slower than my '66 GTO. When I got thru with it, it ran 12.8 seconds in the mid 120s in street trim. Still miss that car.

[@sergiojacquez2277]

You shoulda decline it and made pontiac give you the SD455

[@VirginianSpencer]

@@sergiojacquez2277 That was not the way the world worked back then.

[@clevlandblock]

Same here. I ordered a 73 SD in October 72 and later, the dealer informed me that the SD option was on indefinite hold. So they built me a regular 455 TA. I did some mods and had fun with it for 44k miles.

[@clevlandblock]

@@VirginianSpencer That's right. The dealer slammed the door on my SD order back then autumn of 72. Only 252 made it out the door that spring.

[@TheFastracer455]

Great Video and very informative. All those that complained about the music are the kind that always had to complain about something. Again Great Job my friend !!!

[@larrycavanaugh9371]

Nice video about the car. Why you took the time to fuck it all up with that disco music is anyone's guess...

[@peterhogan9537]

the music in the background is not 1973 or 4. Should have used the Eger Winter group.

[@doctorgonzo2000]

James Brown’s “Coldblooded” would have been good.

[@glennmanchester1568]

Anything would have been better than the one chosen lol at least something from that era ! Nice ass car though I've been a poncho man my whole life more than once I've had to save someone from looking bad and reminding them the firing order of all GM v8s Is the same the distributor runs on the opposite side of the cam gear hence the rotor turns counter clockwise unlike its cousin the chevy so switch those wires around before you try to start this thing and the oh shit your right look on the face or if they have been trying to make it run but can't and for that reason it's an o shit I knew that lmao

[@robertbairt9094]

Deep Purple - Highway Star🌟Radar Love💜 on spoiler. Not "Made in Japan" LolGreat album📻

[@Dirty_Bird]

love the video but funkytown is way too loud lol either get rid of it or turn it down so we can hear you i like listening to this kind of stuff and that makes it difficult

[@timarnott4483]

I wonder if ur still taking comments, ur vid is older, but i have just found it today, so i want to comment......I am a Poncho NUT!!......i was brought up in NJ, and my brother was a good friend of THE MAN NUNZI!!!.....so my stuff works fairly well.......i liked your history, and pics....the lifter valley diffrence speaks for itself!!...WOW!!.....yet we can make GREAT reliable power from our regular 455's....mine was cast Feb 23rd 1970....Still a '70 block...(June started a '71 designation)...i use Kauffman Racing heads, a custom grnd cam, in a '64 Tempest Post car.....i run 11:0's at 120.....pump gas......NON SD block, etc.......so we can make GOOD power.....(car weighs 3450 with me in it)......my math says i'm at 580 hp, and other math says i'm at 615 lb ft of torque.....not to shabby eh?.....REALLY dug the vid...PONCHO POWER!!

[@boblochen]

Good stuff! Always wondered what made it Super Duty. Thanks for putting this together!

[@eastin6868]

What's great is I bought set of TRUE SD heads off a kid for 20 bucks had them checked out for cracks and they are great.

[@JRM137]

Those SD heads outflowed 426 Hemi heads. Just . . . Freaking . . . Wow.

[@ShogMan]

Nice story. One thing to consider - sd heads flow well past .45" lift. even if they didn't, picking a cam that tops out there is counterproductive. Ask yourself if you spend only a couple of degrees at peak flow lift vs. 30 degrees at max flow - wouldn't you move more air? Stay at max flow longer? That's why I usually run .58" lift and tailor the cam profile ramps accordingly to the engine and the type of use.

[@evilswingythingy]

Great Job, very informative and I love Lipps Inc

[@bg147]

It seems the key to these motors were the cylinder heads. From what I understand, the original cam was hotter but it was right on the emissions borderline and they had to adjust the grind which is unfortunate. I would hate to mess with the exhaust but I assume it would be easy to switch it back to stock. The car is a very cool piece of history

[@clevlandblock]

My 74 SD has a matching number Borg Warner ST-10 4 speed trans, one of 220 units. The intact build sheet for my car calls it an "M-21" which is normally a reference to a Muncie gearbox. Perhaps that term was generically used by the factory to label any close ratio gearbox. The question is, were any SD cars equipped with an actual Muncie as this video narrator seems to claim?

[@puppycat65481]

tis the boss of all trans am engines. A friend of mine had a 73 super duty TA, and I had the pleasure of a one on one with the car.......talk about power.

[@michaelreilly1310esq]

The coolest license plate I ever saw as a kid on a brand new ‘66 GTO. It read, ‘SMOKEM’

[@georgeblack3185]

They don't make cars like this often... Pontiac only made 252 Trans Ams with the 455 Super Duty, in 1973, @ 175 with automatic transmissions, and 75 with manual transmissions. I was able to buy a 1973 Trans Am, with the 455 Super Duty from the original owner, in 1977, and the owner had rebuilt the Super Duty 455 for street racing, and had custom painted it black, with flames and grave yard scenes. The screaming eagle was replaced on the hood, natch' :)

[@sergiojacquez2277]

George i believe it was 72 with manual trans.

[@rafaelallenblock]

When I was in high school in 1977 I had a buddy with a white Formula 400 but he always wanted a 455 TransAm. One day his best friend took me for a ride in the Formula, and he promptly crashed it and it caught fire, burning to the rims. The owner took the money from the insurance and bought himself his dream car: A black SD-455 Trans Am. I wonder if he still has that car.

[@Banjo455]

So true Trucking604! They weren't afraid to put it all on the line! Thanks for viewing!

[@xaenon]

Hi! I enjoyed you video - mostly. You should turn the music down when making videos like this. It's very annoying to try to hear what you're saying over a disco soundtrack.

[@phillipthethird42]

I could only fantasize about finding one in a barn with only 20K on the ticker, and completely unmolested , and showing signs of factory markings on it. My next step might sound crazy, but, I would restore it to good working condition and then make it a museum piece.

[@mikepotter5071]

I went to work at McNamara Pontiac right out of high school in 1973. New car service. Got to take numbers of these off the trailers when they arrived, service them and test drive them. Not safe to put a zero mile S.D. In the hands of a ridiculous 17 year old who thrived on tire smoke. Thought those cars would always be there.

[@sergiojacquez2277]

Mike i know exactly what you mean, i bought my 73 T/A with sd455 and 4sp on march of 1979 when i was 19 and i'm very lucky to be alive today i guess it wasn't my time to go because of all the crazy street racing i did on this beast. I'm 60 now and still have my baby till the day i die but plan on passing it on to my son.

[@ramairgto72]

Can't believe I have never seen this video. When I was in HS in 92' I bought my first car, a 1972 Lx LeMans with a 2bbl 350/TH350. As a kid we had a 1975 T/A 6.6 and 1966 Bonneville convertible with a 389 tripower in that wonderful "Frigidaire White" with black top. My neighbor 's daughter was dating a doctor, and being a kid I was always screwing with something under my hood, the doc came over and asked me about my LeMans, he told he owned a 73' T/A SD 455, at the time I didnt know much about how rare the car was. And since this guy was driving a "Turbo Metro" I felt a little bit of a BS going on, but sure enough he showed up in it, he went on to buy over FIVE T/A's SD's and HO's .... One of them came from the factory without any "Call Outs", it was that Hunter Green.... That guy was such a lucky fucker, looking back that guy had to have over a million in cars.

[@Banjo455]

Yeah, if only we knew then what we know now!! Just the same, you probably had just as much fun in that 72 LeMans as I had in my 74 Firebird. It is all about the memories.

[@ramairgto72]

Banjo455 I think I had more fun the LeMans. Ignorance and youth was grand. I would spend so much time preloading my axle, screwing tier pressure to get my open end to hook. I jumped it, reved the snot out of it, got in more drag racers. That car took a beating, shit I would never do again in my other PMD cars. Hell, I don't even park by the doors when I go shopping, I look out for where the shopping car return is! With that LeMans I used to push shopping carts to 50mph! LOL

[@jgossy5478]

You are a lucky man to have such a great Pontiac.

[@zwild1160]

Forget the music the SD455 was a great engine. Truly the best power plant Pontiac made including the venerable 69-70 Ram Air IV which made more than 370.

[@joshbrekke6374]

ZWILD1 actually the SD 421 was 488hp and 493tq and with a lil work that most of the racers did in 1961-63 it was well past the 500hp mark and Torque. All with “D” port heads. Fact

[@tunnelportterror]

the compression was too low as issued in 1973-74. but it made a great kit to start from. mill heads .065" small domed pistons aluminum intake, Holley carb bigger cam or better yet, put milled RA IV or RA V heads on it, then presto you have a kick ass race motor. a solid foundation and framework was there for 600-700HP race motor, with 13:1 compression

[@Banjo455]

TrumpetBob mentioned that all the SDs were Borg Warner Super T-10s and he is correct. Muncie went on strike so Pontiac went to the BW trans....but, they maintained the M20 and M21 designations on the build sheets for some reason. In 73, they only offered the M20 wide ratio BW Super T10. In 74 they added the M21 close ratio BW Super T10 but didn't put it on the options list. Unless the salesman told you the M21 close ratio was available, the buyer had no way of knowing, therefore, the number of SDs with the M21 is very low. I think TrumpetBob thought I was saying I had a Muncie trans in my car so hopefully this clears up any misunderstandings.

[@13spdRoadranger]

I have a 1974 that was originally a 400cid car and I still retain the original fine spline Muncie close ratio 4-spd. It's holding up well against a 462cid dyno proven 500hp, 562ftlbs. ;)

[@racer774]

Banjo455 An excellent video with info I never knew about the PMD P&A bulletin regarding the verification of SD ownership to purchase the rods and miscellaneous SD parts after supplier shortage was revealed. My cousin ordered/purchased a new 1974 Formula 400. I did my best to try and convince him to purchase the SD engine option. At the time, he said he didn't want to spend the extra money (which was a bargain even then) and that he didn't plan on racing his car anyway. He still owns this car and it has a rotisserie restoration. -- Fast forward to about 2005. My cousin wishes he would have listened to me about the SD option. For many reasons, IMAGINE THAT! I agree that the Funky Town was unnecessary but if nothing else, the volume level of the music was too loud in relation to the dialog. Thanks for the video and indeed you have one of the most impressive and last of the true, classic muscle cars.

[@clevlandblock]

Right on. My sheet says M-21 but I have a #s matching ST-10 (2 rings on input shaft equals close ratio 2.43 first gear) in my 74 SD.

[@oldschooldirtbikes9960]

Great video and don’t mind the music....I picked up a 1973 455 SD motor and trans only about 30 years ago. It’s been in my heated shop ever since. Is there any casting numbers that I can check to see what type of 455 this is?

[@chutoparadinni5474]

You said it was a 73 455 SD?

[@chutoparadinni5474]

Look for 490132 that's the main one, than it comes down to the correct pieces, carb, heads, intake, distributor and the rest

[@oldschooldirtbikes9960]

Thanks for contacting me back. I have a 77 TA and came across this 455 with 400 trans. I never looked into it because they are so rare but you never know. I will have a look at the casting numbers and send them back to you.

[@clevlandblock]

Good video. Nice job. There are a lot of really misguided dudes out there in the blogosphere when it comes to Pontiac V-8s. Hope this helps them a little.

[@LuciFeric137]

Nice video. Ive owned...68 GTO, 74 TA (400, 4 spd), 79 TA (403 auto), 83 TA, 84 fiero. Best car? 74 Trans Am.

[@willd.5406]

great video..... now im debating wether I should build the 455 instead of my 400

[@gregbarnes7913]

Will D. build the 455, set the Compression at or near, 9.2:1,, then let the torque lay you back in the seat!!

[@mountmepython2206]

I say build the 400.

[@joshbrekke6374]

Build a 400 with a 455 crank or larger 4.50” stroke. Just make sure you go with 4bolt mains. Less rotation weight and still all the torque, more actually because of less weight

[@brenthill3241]

Enjoyed the technical analysis but I had to leave halfway because like sooo many youtube videos there was loud distracting music.

[@trumpetbob75]

All 74 4 speed SD-455s came with the Borg Warner ST-10 transmission. All 212 of them.

[@clevlandblock]

That's my understanding but this video narrator thinks his is a Muncie. Muncies were put in the 71-72 HO cars.

[@klrviper]

Absolutely incredible video!!!! The funky town was annoying!!!

[@sergiojacquez2277]

Had lots of fun back in 79 when i got my 73T/A SD-455 4sp Buccaneer red. This song was always on the radio back then and had lots of fun with car and having fun in back seat, if you know what i mean. lol 🙃

[@mercoid]

Very informative. Nice work.

[@bradlybaldwin9564]

Well said

[@jayelbee1111]

Which GM Division had the best big block? Chevrolet 454, Pontiac 455, Buick 455, Oldsmobile 455?

[@flyonbyya]

I had a friend who had one in the late 70’s...I was 16 years old at the time I loved that car I didn’t really know what it was at the time Ive often wondered what happened to it

[@len-zeplin480]

My Dad Worked at our Local Pontiac Dealership. He knew this Information inside & out. He Always said MOST S.D. 455 Cars were Phoney Ponies. He Loved the Firebird & Grand Prix 428 cars. He told us that the Bird on The Hood was "FOGHORN LEGHORN" Because every Time He Roasted the Tires, He would say, "Smell the Fried Chicken! "

[@chutoparadinni5474]

Phoney Ponies??

[@len-zeplin480]

@@chutoparadinni5474 The Information in This Video is Dead on Correct! I've seen people buy a Rebadged Clone Car that said "455 SD" on the Scoop. They Pay $60,000+ For The car only to Find out it has a 400 out of a Boneville in it.

[@chutoparadinni5474]

@@len-zeplin480 I get you, Indeed, lots of SD 455 shakers out there, most are fakes. good one

[@insulman100]

From what I've heard a lot of the engineering came from the RA V program but of course the SD 455 didn't have the tunnel port heads nor the RA IV cam grind believe it or not the SD grind is milder

[@74SD455TA]

The EPA forced Pontiac to put the milder cam in there to certifiy. Such an easy swap to the Ram Air IV style cam.

[@insulman100]

@@74SD455TA yup the EPA forced Pontiac to de-tune the 455 SD a lot but not an easy swap well it's easy to replace the cam but to take advantage of the grind you would need to increase compression add open true dual exhaust(no cat converters) re-tune or replace the carb ect.

[@74SD455TA]

@@insulman100 I own a 1974 SD 455 T/A and it has the Nunzi grind Ram Air IV style cam in it. Compression stands at under 9 to 1 and in no way required increase to support the cam change. What really woke this torque monster up was rejetting the carburetor. So, nothing complicated to a good tuner. With these changes, my SD is capable of lower 12 second runs. The exhaust was never a worry since the SD was done before the mandated catalytic converter. .

[@danieldelgado3008]

excellent video, really enjoyed it

[@doctorgonzo2000]

Will somebody please take that chick to Funky Town, already?

[@sergiojacquez2277]

lol

[@Ramitupyourkilt]

Thanks for that!

[@wilde.coyote6618]

The narrator reminds me of Warren Miller.

[@rickj1983]

At its full potential, what HP and Torque will this engine produce?

[@AzureKnightmare32]

Nice vid, very informative

[@robertclymer6948]

Didn't Pontiac have a 421 super duty that Ernie Beswick (the flying farmer) ran in the 60's ???

[@chutoparadinni5474]

Yes, but completely different than the SD versions of 73-74

[@robertclymer6948]

@@chutoparadinni5474 Thanks for the info!

[@SLJ2137694]

Robert Clymer his name is Arnie.

[@haroldsimmons9623]

Great video. Now turn the music down so that some of us can hear and learn better. Damn

[@RealDougFields]

The SD455 was a special engine but it was not released as hot as it could have been. 400 RA 2's and RA4's were hotter though.

[@1967davethewave]

Did you say that they enlarged the distributor gear and made the cam gear smaller? That would make it impossible to keep the distributor in time as the gears between the cam and distributor have to be the same size. The valves on the 455 SD heads were no larger than any Pontiac performance head from 1967 to 1972. They were swirl polished, undercut and better materials. The first few 455 SD's produced in '73 received the 041 cam while the majority of '73 cars and all '74 cars received the 068 cam due to EPA tailpipe regulations. The 455 SD didn't receive a special cam. Also claiming that the heads would outflow a 426 Hemi is way wrong. SD 455 heads will flow about 245 to 255 cfm on the intake side which makes them the best factory Pontiac heads except for the Ram Air V. A stock 426 Hemi head will flow 310 cfm or so on the intake side. Where did you get this incorrect info? I love the 455 SD although the 3.25" main journals always limited their high rpm potential due to reliability. Best to give accurate info. Facts always rule over hyperbole.

[@chutoparadinni5474]

No they did not, ALL 73-74 SD's were the same! same cam, everything, that's a myth from early articles that were released before production. NO RA IV cams in ANY Regular Production SD's!

[@clevlandblock]

Regarding the comparative cylinder head flow I have a car magazine article quoting an Airflow Research engineer stating that the SD heads do outflow the Chrysler hemi. They developed the SD head configuration for PMD.

[@1967davethewave]

@@clevlandblock Well I would have to say that article is wrong. I have several that show the flow of the Super Duty 455 head stock and it is always around 245 to 255 while the 426 Hemi is around 320 cfm or more. Look, I love Pontiacs but that doesn't mean that I'm not realistic. They don't have to be the biggest and the baddest to be the best, and they are the best. But even the Ram Air V head falls short of the flow of the 426 Hemi. Here's my reference, I didn't test these myself. I'd be glad to look at any reference materials you have if you want to provide a link. www.users.interport.net/s/r/srweiss/tablehdc.htm

[@1967davethewave]

@@chutoparadinni5474 I didn't do the research, that came from the pages of High Performance Pontiac. If you have different information I'd love to see it. I know that over the years things that were once gospel can be found to be myths. No reason to start a fight though but instead share the information so we can all be properly educated.

[@Pontiacman1964]

What was the true factory horsepower rating of this engine, and what was the reported horsepower rating?

[@danv8717]

Rated at 290, but it was more like 400 horsepower!

[@jasonhumphry5836]

Ah but it was Oldsmobile and Cadillac that invented HOTRODING

[@jeremythompson9122]

Imagine the horsepower the 455SD would've made if it was built in 1969 or 70 instead of 1973-74. It might've gone down as the baddest street engine ever made by any manufacturer during that time if Pontiac was allowed to use high compression pistons and a solid lifter camshaft in the 455SD..which they would've been able to do in 1970 or prior. With high compression the 455SD would've been good for 500 horsepower very easily...maybe more. The 455SD cylinder heads are maybe the best breathing heads ever designed...maybe even superior to Chrysler's Hemi head design. Pontiac being able to get the kind of horsepower and torque that they got from the 455SD in 1973-74 is nothing short of incredible. A stock 455SD had to be making at least 400 plus gross horsepower in order to move a 73-74 Trans Am down the 1/4 mile in 13.5 seconds. The 73-74 Trans Am/Formula Firebird 455SD is one of the quickest cars of the whole muscle car era

[@1967davethewave]

I'm a Pontiac guy through and through so what I am saying is just fact, 455 SD heads were the 2nd best factory Pontiac heads with the Ram Air V being the best. But 455 SD heads are only moderately better than Ram Air IV/455 HO heads and none of them are that great. 455 SD heads flow about 255 cfm on the intake side which is just a little bit better than a 5.3 LS motor, they flow about 225 cfm. A 426 Hemi head flows 310 cfm or a little more on the intake side and a modern 392 Hemi will flow 345 cfm. A rectangular port BB Chevy head from 1970 flows 290 cfm while the low performance BB Chevy oval port flows 270 cfm. And the Boss 429 heads flows over 370 cfm. The 455 SD head was a very good Pontiac head but it was far behind a lot of the competition.

[@captaindaddy8645]

i dream about a 69 trans am clone with a 73 455 SD swap.i would try and get the nascar transmission and dry sump system. i concoct mash ups all the popular kibbles and bits into one vee-hickle. when im into my third pina colada. like the pina colada itself.

[@karlepaul6632]

Adjust the volume brother....😳

[@trucking604]

I know I’m being picayune but Funky Town does not fit that era. Funky Town came out in 1980, the 455 SD ran from 1973-1974. I think Rock The Boat by the Hues Corporation which came out 1974 would have been more time appropriate.

[@BizOrNot]

Bought a '74 Sd455 TA in 1980 for $4K, sold it to a buddy 3 yrs later to pay for college, for $7K. Thought I was "in the money." The engineering degree was worth it......I guess;-( Now I have a '62 GP......Pontiac rules!

[@raymondwagoner4896]

in 74 they lowered the compression ratio so low the 455 had about 180 hp, actually compression was lowered in 71.

[@chutoparadinni5474]

290hp rated, in reality around 350

[@joshbrekke6374]

But the torque was insane as with all Pontiacs, we know what torque does right? It moves stuff, heavy stuff too. Like the T/A in 74’ with that boat anchor of a from bumper

[@victorialouden1912]

built 5 mins from my house at the NORWOOD ASSEMBLY plant the home of the F body

[@curtismuma1931]

Great video. the dam music was loud. I cant hear you.

[@Mbartel500]

The loud obnoxious soundtrack is a distraction from an otherwise good video.

[@neighborscomplaint6859]

A 7,000 RPM capable engine saddled with an emissions compliant 068 spec cam that was out of gas at 5,000 RPM. In reality, the rods swinging those big, heavy pistons would never have supported 7,000 RPM ... for very long. The 400 would have been a better choice for the SD modifications.

[@74SD455TA]

Aluminum pistons big/ heavy? However I wouldn't dare risk detonating an extremely rare Super Duty Engine to which there may only be about 300-500 left in existence

[@stefanskala6696]

i eant a sd 455 awesome car smoky and the bandit

[@joseywales4874]

Qjet powered instead of the Holley junk

[@crazyoilfieldmechanic3195]

I know this is an ancient video but I watched it to see if it had any info I hadn't already heard. It didn't. I'm very curious if you watched the video you made before you posted it because I find it difficult to believe that anyone would put that stupid awful music up so loud in what was supposed to be an informative video.

[@ethanmiter7813]

0:34 my brain during school

[@scottmcgehee2933]

Absolutely no reason to have any music in this video. It just is an annoyance.

[@shawnrenaud2252]

Informative video. Too bad the music makes it harder to easily follow.

[@darrellsomers5427]

I always thought they should have put the SD in the X body GTO

[@joshbrekke6374]

Darrell Somers , GTO is an A-Body. You can build a 1967-79 400 a hell of a lot more powerful and badass then the 455SD now days with all the great aftermarket parts and technology available today at at lot less money then a real SD Block alone. FYI

[@darrellsomers5427]

The 74 GTO is an X body that's a Ventura /Pontiac nova and the 455 SD head has flow # bigger then a hemi no stock Pontiac head does that except a 455ad the SD is a different animal then even a 455 HO

[@darrellsomers5427]

455 SD

[@darrellsomers5427]

The block is different and the rods are good for 1000 HP

[@joshuabreeding4907]

Music is distracting.

[@arcorob]

This would have been fantastic...minus the music which was too damn loud

[@janhill7383]

Yes, kill the music. I have enough trouble hearing without the noise

[@ginnroad]

Makes me sorry I sold my Hurst Olds Cutlass, 74 W30, 455SD.

[@audieconrad8995]

Just loved the tutorial BUT the music drove me to total distraction...wtf...

[@chutoparadinni5474]

Ignorant Haters gonna Hate!!

[@bryantcurtis2665]

Should be near rated by Snoop Dogg. And music by pitbull

[@cswango1714]

I guess I enjoyed the song more than what you had to say since you opted to drown your own voice out with the music

[@jimporter7602]

I tryed ording a set of those rods at the local dealer in 74, the set was $150 and then they showed me that paperin the vid and you also needed a vin number ha ha not going to happen, did get to order a set of 1.65 rockers and 11/32 push rods in same package for 68 1/2 RA4 P/N 9794325

[@timothycoyne7253]

PONTIAC..........

[@jayrowe6473]

Good video but TURN THE MUSIC DOWN! It's supposed to be barely audible and the main attraction is supposed to be the information you're conveying with your voice. If I wanted to listen to music I'd turn on the radio.

[@pl5624]

Mean mary jean pushed plymouth not pontiac...

[@maxxmasson4263]

the song in the background is annoying ,distracting and too loud for the video

[@j.j.springer1099]

Turn radio off

[@dr.detroit1514]

It'e really too bad this engine couldn't have come out in 1970. With high compression, ram air 4 cam and 1.65 rockers, and no serious pollution equipment requirements, this would have been Pontiac's Super Bowl engine to compete with the likes of the Chevy 454 LS6, Buick's Stage One and others of that zenith year for performance. Pontiac had put too much time and money into the Tunnel Port Rabbit hole, and with Delorean gone, had no direction or money left.

[@clevlandblock]

I've read that that was the original plan by PMD. That is, that the SD 455 was supposed to be ready for the 70 model year with high compression and RA 4 cam. In any event, it's odd that PMD didn't just convert the existing RA4 to 455 cubes and go head to head with the other GM division offerings of the day.