(first posted 12/23/2014) Cohort poster William Oliver has found something approaching a unicorn: a Pontiac Astre, but not just any Pontiac Astre. It’s the final year 1977 model, which was the only one to have Pontiac’s “Iron Duke” 2.5 L four under the hood, replacing the ill-fated Vega 2300 engine. The only thing that can top this would be the 1975 Astre “Li’l Wide Track” model. Good luck finding one on the street. But this is plenty of motivation to take a look at the Astre’s less than stellar history.
The Astre first saw the light of day with its curious split grille in 1973, as a Canada-only model. Pontiac had an unusually large presence in Canada, with its locally-built “Cheviacs”. But wanting to get in on the sub-compact market too, the Lordstown, OH. plant started spitting out these, headed for Canada. Mechanically, they were identical to the Vega, and the change to the grille was minimal.
In 1975, US Pontiac dealers finally got in on the Vega action too, just when Vega sales began their terminal decline. Astre sales were very sluggish, so the “Li’l Wide Track” appearance package was created. It didn’t help much either; some 3,000 were sold from the factory, and more were dealer installed.
The Astre was just a Vega with the optional Custom Interior as standard. But there was also an SJ package, which turned the Astre into a genuine hot-date mobile. Or not.
Despite looking quite similar, 1976 Astres (and Vegas) had a number of substantial differences under the skin, reflecting many of the changes made for the H-Body Monza, Sunbird, etc. These included a new box-section front cross-member, larger rear brakes, and a new “torque link” rear suspension, that tamed the rear axle hop so easily induced by the rubber-shredding 70 hp (84 hp optional) Vega 2300 engine, which also had a number of improvements and was now called the “Dura-built 140”, and not ironically.
But for its final outing in 1977, the Astre was bestowed the 2.5 L Iron Duke, with 84 hp and a bit more torque. The Iron Duke was a Pontiac engine, derived from the 301 V8, with which it shared some of its architecture.
Here’s a quote from a Car and Driver review of the 1977 Astre, which I found at Wikipedia: “The Astre is the Vega – polished and refined and significantly improved, but still a Vega in perhaps its ultimate state of development..It remained for Pontiac to do what Chevrolet probably should have done in the first place: the substitution of the marvelous old Chevy II cast-iron four-cylinder econo-motor for the much-troubled aluminum-block Vega engine. Sliding in and starting the engine was a revelation because it’s so quiet and smooth compared to the Vega.”
This is quite the compliment they paid the Iron Duke it for being so much smoother than the Vega engine. It just proves that everything in life is relative, because it’s undoubtedly the only time anyone ever paid that unruly lump a compliment on its quietness and smoothness. That does say something about the Vega engine…
The Astre didn’t really go away in 1978; at least not the wagon. It was just re-badged as a Sunbird, and built for two years to round out the Sunbird line with its hatchback and coupe. The Vega wagon also morphed into the Monza wagon in the same way, and it too got the Iron Duke for 1978.
Now someone just needs to find us a Sunbird wagon in the wild, or even a Monza wagon. I wouldn’t be shocked.
I almost chocked on my coffee when I read smooth and Iron Duke in the same sentence. I was a kid when Vegas came out, never rode in one. They all vanished by 80.
I can’t believe anyone would ever have called the Iron Duke smooth, I guess all things are relative. The alloy four in the Vega was loud and thrashy but almost all four cylinder engines were then, especially the ones larger than 2.0 liters. My 1973 Vega was neither smooth nor quick but it did handle well, particularly when compared to the average full-size car. People rag on the Vega, and deservedly so, but they did have some good qualities.
I gotta admit they are one of the best looking compacts of the era.
My dad had a couple of Pintos and a ’74 Vega GT and it was his opinion that the Vega was far more fun to drive than the Pintos but the Pintos were far more reliable.
What a shame the customer had to choose between fun OR reliable.
Should say reliably explosive
The only good looking one was the fastback coupe, in Vega or Astre versions. G D shame that they were cursed with garbage engines and non existant quality control.Finding a decent one nowadays is a fool`s errand.
Yes the Vegas and Astres did haven some good qualities. My Vega GT was well equipped and able to go 80,000 plus miles before an engine rebuild.
I put on 13,000 miles of that when my buddy and I did a six week road trip through the U.S. and Canada in the summer of 75. No breakdowns on that trip but the engine did overheat in California (of course). A slipped drive belt followed yet we managed over 30mp until a tuneup in Texas and a new drive belt allowed us to carry on with no further issues
The one you forgot was the 1977 Pontiac Astre Formula. I owned one. Great looking little car and fewer than a thousand made. The car was light and the iron duke made the thing move. There wasn’t a small block around here that could beat me in the 1/8 mile (that’s the distance of our drag strip here). Yes, the duke vibrated…enough so that I repaired the upper radiator hose lip multiple times. Wish I had it today for car shows. Never have seen another.
Dennis, I just saw a blue Formula in a parking lot in NW Arkansas a moment ago- that’s how I found this post! It was in decent shape, and had Buick Turbo 6 badges on it….now that would be a hot swap.
I’d like to see that car!
Still have a silver FORMULA wagon!
Actually, Pontiac engineering spent much time and effort to create a smooth running 4 cylinder, the Iron Duke really doesn’t shake and vibrate like many 4 cylinder engines.
I always thought of the Astre/Vega as being about the same as Ford’s Pinto/Bobcat. Just about everything Chevrolet built, Buick/Olds/Pontiac had to have their own version as well. Ford and Mercury were much the same. A whole lot of duplication going on. But the Astre should have been a much better car than the Vega because of the Iron Duke engine. Unlike the Vega’s aluminum fiasco, the Iron Duke was one of the toughest little engines ever built. My 1987 Pontiac Fiero had one.
Ford seemed so confused about Mercury- that division slummed around in cheap Ford Land, Comet and Bobcat and such and wondered around Lincoln Country, Marquis for example. Now I worry for the Lincoln Horseless Carriage Division.
For the 1975 model year, Pontiac turned down a Monza clone, and instead took a Vega clone. But, after sales bombed, then they got the Sunbird for ’76, and was a notchback only that MY. Then the fastback Sunbirds appeared 1977-80.
We nicked named them Pontiac Ashtrays.
Here in Qc we nicked named them Désastre & Dégat , that stand for Disaster & Damage . Nickname give as soon as they leave the factory here in Sainte-Thérese , province de québec .
1985 or so – my girlfriend at the time had one in bright orange. Drove it from NJ to Annapolis to visit her brother at the Naval Academy. We stopped somewhere for a break – and came back to to find the car wouldn’t start. Let it sit for awhile and it turned right over. She called it the ashtray too.
I remember seeing these when I was a boy. I saw one parked next to the Vega, and I found the Astre’s nose more attractive than that of the Vega.
I can’t help but like these…I know they’re junk, but they look cool and I love an underdog.
The Vega/Astre hatchbacks were great LOOKING cars. Style they had in spades. But the mechanicals didn’t measure up. The Monza and it’s BOP counterparts were also cheaply built. I don’t know about the engines, but I remember seeing quite a few back in the days when they weren’t that old, the doors were falling off (these things had long heavy doors) as well as the front and rear fascias. It seems like the Ford Mustang II was built a lot better than the Monza.
About the engines ? For the ’79 Sunbird- ,you could get a 3.8 v6 . I remember that I often lost the rear-end with it .
Hey Aaron. I agree. Another car I’ve come to like are the AMC Matador and the AMC Concord, and the Eagle. The Pacer was ugly, particularly with its grille elevated an extra floor. But it wasn’t awful looking. If I got to ride in one, I might enjoy it.
This car is such a case of ‘what could’ve been’. Rather than making a ‘compliance car’ and doing a half assed job out of spite, they could’ve went for affordable sportscar. Just think what a warmed over Buick 231 V6 could’ve done for this mated to a 4spd and if it was put together with some level of build quality. 240Z who?
The top engine option in the ’80 Monza was a 231, and I believe you could get the four-speed with it, too. Too little, too late.
Late 70s Monzas offered the 305 V8.
Me too! Long live the AMC Pacer, Lincoln Versailles, and Cadillac Cimarron!
You can keep the Cimarron. A most un-Cadillac-like Caddy. Eww!
I think James K. Polk was the President the last time I saw an Astre ‘live’ on the road . . .
Had to Google him – you’re that old? 🙂
I had an ’80 AMC Concord wagon with the Iron Duke and a manual trans and I don’t remember it as being all that rough. Damn car was killer on gas tho, I could easily exceed 30mpg highway.
It seemed to be a bit smoother in North-South RWD applications.I drove a Phoenix taxi with one, and it wasn’t too bad for the times, as long as one didn’t try to rev it too much.
In transverse FWD applications, it seemed to transmit more of its vibrations, sometimes quite badly. Presumably the RWD versions were able to use softer motor mounts. Also, the Concord had pretty good sound insulation.
No one would dare to build a 2.5L inline four in modern history without balance shafts, which is what the Iron Duke should have had.
I may be wrong, but didn’t the later Iron Dukes have issues after they changed the valve drive gears to plastic? Otherwise they were nearly Slant 6 robust.
This could very well be, though the Iron Duke used a gear driven cam. Most of the plastic cam sprockets were used in conjunction with a timing chain and a steel crank sprocket. The 318 in my ’70 Challenger blew up when all the teeth sheared off the cam sprocket. My understanding was manufacturers used plastic to make them run quieter. That was a really dumb place to use plastic. Some years of the Slant 6 used a plastic distributor drive gear. I remember breaking one on my dad’s early ’60s Valiant when I hooked up a couple of plug wires wrong.
I have a straight cut geared cam drive on my 383 powered S10. Yes, it has a noticeable whine, but I kind of like it. Sounds almost like a blower whine. I never cared for quiet cars. To me a car is a machine, and machines are supposed to make mechanical noises.
“To me a car is a machine, and machines are supposed to make mechanical noises.”
Agree, 100%. Silky smooth and silent isolation pods are great for the cammacord set (read, non-car people) and they have their purpose. That crowd would likely gripe that they cant hear NPR or smooth jazz if the car made any noise at all.
When I brought home my ’03 PT Cruiser GT I was completely baffled by how much effort was made to stifle the sounds of this car. I mean its styled after a hotrod, and it has hotrod power…why shouldn’t it sound and feel the part? I ripped out all the sound deadening from under the hood, put in a CAI and straight piped the exhaust then added a blowoff plate. Not only did that uncork some much needed airflow and vent off heat from under the hood, it unleashed that car’s inner hooligan. The exhaust had a throaty and nasty snarl appropriate to what it could do. The shriek of the spooling turbo and the “PSHH!” evertyime I shifted gears followed by all the snap crackle and pop of unmuffled backfires scared the bejeezus out of more than one sleepy driver beside me! That little car never failed to put a smile on my face.
“To me a car is a machine, and machines are supposed to make mechanical noises.” Can I have an “Amen”???
Some mechanical noises are a lot more pleasant and appealing than others.
Paul, youre right about that. The Duke might be a reliable motor but between it and the cadaverlier’s 2.0….did any engine sound more like a metal bucket full of rocks going down the road?
Old thread I know, but I gotta say sometimes I like to drive in silent isolation- when crossing a few states at seventy-five for instance.
No damn Camryccord for me, though. Gimme an old New Yorker.
Forget the isolation pod. I want an Isolation Cathedral!
The Iron Duke did finally get balance shafts in its final iteration, around 1989. Don’t think it helped much though.
The ridiculous thing is that the later Quad 4 didn’t have them either (until it was no longer called the Quad 4, at any rate). The Iron Duke/Tech IV was at least a lugger of a thing, with more torque than power, but the Quad 4 was supposed to be a high-revving engine.
And most had three speed slush boxes with overwide ratios.
I was lucky to turn the pages of the original 1976 Pontiac catalogue… By the way it still keep the stamp of the then official dealer of Vienna Austria.
Nice looking Pontiac and I assume that cement pillar in front of the rear wheel is a removable wheel chock.
Optional parking brake 😀 !
does anyone know if the rear tail lights are just a rehash of the 67-68 firebird lights just recycled from the parts bin or where they somehow different?
I’ve always thought these were neat looking little cars. And I always thought they should’ve put the Iron Duke in there from the get-go. It’s nice to learn that they actually used it in the final year!
Loved reading this post! I always wanted to know more about this car. The 1973 in the picture looks like a 73 Olds Cutlass!!
I thought the same thing, Gerardo.
I also dated a girl in 1985 that had a bright orange 1977 Astre. We always took my car, so I think I drove that Astre maybe once in the 6 months that we dated. IIRC I think it was a manual 3-speed. It even had the rare Trans-Am steering wheel option with a tilt wheel. She was always afraid it was going to break down so eventually she traded it in for a new Hyundai Excel in 1986.
Ooof… out of the frying pan and into the fire! Those early Excels were pure rubbish.
Wow, I had forgotten about these. John DeLorean had indeed left the building.
I vaguely remember walking past these on the way to look at a new Honda Accord. The local Honda dealer was also a Pontiac dealer (you can guess which franchise worked out better) so I got to see Astres, Sunbirds, Fieros and the Daewoo “LeMans” on visits forservice or to check out new models. Even as a 12 year old, a badge engineered Vega held no attraction for me.
I’ve done more Vega-bashing than just about anyone on here lately, and I also chuckled at the “quiet and smooth” iron duke, having had a Tech-4 S-10. Still, I am stunned at the condition of the subject vehicle, given that most rusted to oblivion. I haven’t seen any Vega/Astre on the street in years. Particularly in hatchback and wagon forms, it was a great looking little car, IMHO.
To go with Roger’s comment on mileage, one of the 2.5 S-10’s few redeeming virtues was that it’s the only pickup I’ve had that would get 30+ mpg. These days, most of the remaining small trucks still on the market don’t seem significantly better than the V-6 full-sizers.
My sister bought a 74 Astre hatchback in 1980 for $250. Aside from using a quart of oil every 2 weeks it was quite reliable. It had the best heat of any car I’ve ever experienced and even in minus 30 prairie winters it was always toasty warm inside. She drove it a few years then gave to my father who drove till the late 80s. A year or so after he sold it the police came to the door and said they found “his” Astre abandoned somewhere. The guy who bought it had never had it registered and they just wanted to make sure it wasn’t stolen. My father remarked that he was surprised that it was still running to which the police woman replied “yeah it’s still rattling around”. I wonder if teens today would be as thrilled as we were with a rusty oil burning little car like the “Ashtray”.
My 7th grade teacher, Sister Loretta Mary, had a medium brown 75 Astre she affectionately referred to as “the puddle jumper”. She always parked the car tail out in the convent parking lot that was attached to the grammar school. The slotted tail lights were sharp and reminded me of a ’67 Grand Prix or a ’67 Firebird. She adored that car.
Apparently, she never drove it much.
An otherwise appealing car in dire need of a small block Chevy engine implant.
I owned a 72 Vega and 76 Pinto, between them was a 74 Audi Fox. The Fox was the “fun” car of the trio, the Pinto was the best assembled, and the Vega was…..quirky. One afternoon, I stopped near the beach thinking I might take a walk on the sand. I soon changed my mind but when I tried to pull back into traffic I found myself stuck. With just 1 rear wheel on the soft shoulder, I found I could not get the car to move. Assembly “quality” of my 2nd year Vega was very patchy. And yes, the doors were heavy, but so were the doors on Pintos. By contrast, the Audi felt like it was built of aluminum.
Can someone please tell me the correct way to pronounce “Astre”.
Is it, “As-Tra” , or is it “As-Ter” ???
I assume it to be, “As-Ter” like the way you pronounce LeSabre (Le-Sab-er)
IDK, I never seen one of these in my neighborhood, and if you did, the Brooklyn accent butchered it up anyway!!!
SMH LOL
As-tree-or As-tray
Ass-truh.
Both “Astre” and “Sabre” are French words and they sound as if you simply wrote “Astr” for the “Astre” (“astʁ” in phonetic aplhabet) and “LeSawbr” (“ləsɑbʁ” in phonetic alhabet) for the “LeSabre”!
Note that the “A” in “Astre” and “Sabre” aren’t pronounced exactly the same and they have different letter codes in phonetic alphabet. The first “E” letter in “LeSabre” is pronounced as the “a” letter of “about” (and usually pronounced correctly in English) but the “e” is silent at the end of both “Astre” and “Sabre”
When I first heard “LeSabre” pronounced “LeSayber” in an English-language ad, I thought it was funny how they pronounced it!
I didn’t know that. I’ve never heard Astre spoken before. Like many people, I’ve heard the name LeSabre, as in Buick LeSabre. It always sounded like “LaSaber.”
I’m impressed! You know your English well. Wiktionary.org also describes the proper pronunciation for Astre as you describe it. Up north here in Canada, we always pronounced it the correct way. I guess that’s due to the bit of Français in us!!!
As for me I always pronounce it “Astrey”
To be pronounced like that, it woud have to be spelled “Astré”
Like the Plymouth Volaré (which I think is Spanish, not French). Volare without an accent on the “e” is Italian.
Nice lesson in linguistics, Phil. 🙂
Either way, producing a car that your clientele can’t correctly pronounce is perhaps a questionable move…Parisienne anyone?
And don’t forget about “Merkur”! 🙂
I’m pretty sure the car Volare’ was meant to be the Italian word, I believe they added the accent so that Americans wouldn’t pronounce it Vol-air. They used the Italian-American song in the commercials. Also it makes more sense in Italian as it means “I’m flying” vs. in Spanish “I’m going to fly.” As for the Astre, growing up we all pronounced it Aster, like the flower.
From what I read on Wikipedia, the former GM Sainte-Thérèse plant in Quebec, Canada also assembled a batch of Vega/Astre in 1973-74. https://en.wikipedia.org/wiki/Sainte-Th%C3%A9r%C3%A8se_Assembly
In French, we nicknamed the Vega as “Dégat” (French for damage, defect, flaw) and the Astre for “Désastre” (disaster).
The Ste-Thérèse Plant also made other “H” and ‘”J” bodies, including the Olds Starfire that never sold in Canada!
When I was a kid, I remember one of my uncles had an Astre that he raced. It didn’t have it’s 4 cyl anymore! (and I can’t tell if this one originally had the Iron Duke or the Vega engine!).
HA! Great pictures William – I’ve been meaning to shoot this for years.
The Astre has been sitting at the same garage/used car lot on Dundas St. W .in Toronto for 2 or 3 years.
I can’t recall if there’s a price on it or not….
I’ll have to take a ride on Dundas West sometime. I haven’t see an Astre (or Vega, for that matter) in many years, and I haven’t seen anyone driving one since the mid-’80’s.
Dundas @ Lisgar. If you want more fun, swing up Ossington and then down Dupont. There are some interesting low-end lots in between the high-end stuff.
A body shop up there has a 90s looking Avanti on 4 flats.
nice car, I remember seeing one in Spokane, Washington last summer that appeared to be in good shape and did a total double take seeing that car, that was the first time I have seen one since maybe the mid 90’s, I actually think these cars look far better than its Chevy twin.
I graduated from high school in 1988. When I was a freshman, there were still a few Vega-shaped cars in the student lot. I learned then that they weren’t badged as Vegas, and the ones powered by Vega 2300 engines were gone. Like the Triumph TR7s, the Astras, Sunbirds and Monzas would be memories by my junior year.
Here’s a pic of the 1976 Pontiac Astre Estate wagon with “wood” side paneling. I love the woody look on small cars!
Nice looking car. I’ve always thought the Astre looked more attractive than the Vega.
Wow funny enough I was walking around Toronto last Spring and I took pictures of the same car. Drove by recently and unfortunately the car as well as the business there is gone. Looks like it is slated for demolition
I found it! Where was it in toronto?
All the negative comments aside, I love my car!
While crude by today’s standards these little cars look better and are/were way more fun to drive than today’s front-wheel-drive tinny cars IMO. The 2300 Vega 4 engine wasn’t nearly as bad as people make them out to be today, especially the later “Durabuilt” engines. The main problem was GM put too small of radiators in these cars and people would let them overheat which ruined the aluminum engine blocks. Except for using some oil I never had any problems with the 2300 engines in the H-bodies I owned and I put many miles on them.
I had a 1976 Astre with the GT package, and that’s a car I wish I still had because it was a real looker and fun to drive. Now I have my 1977 Vega that I had in college which I sold and later bought back. I am restoring it back close to how it was when I first had it. I plan on keeping the original Vega engine in it, too, just to show people that these engines aren’t the junk people think they are. It’s the same color as the featured Astre: Chevy called it “Light Blue” and Pontiac called it Lombard blue. It’s the color Pontiac more famously used on the “Skybird” special edition Firebird.
i had a 76 hatchback. Forest Green tan int. Car was a blast to drive and i put over 100,000 miles on it when i sold it. it would burn rubber in first and chirp in second. it was a 4-speed. Loved that car wish i still had it.
I still have mine! 1977 Pontiac Astre Formula (without the decals)
Sorry, upside down photo…let’s try again
If you ever decide to sell the formula let me know. I owned one as my first car and have been searching for one since.
’79 Sunbird Sport Safari
My first car was a 1977 Pontiac Astre Wagon, much like the one pictured here, but in a lovely shade of beige! Not exactly a chick magnet for a newly graduated 17 year old guy about to start college in 1986…but it got me where i needed to go!
My first car was the Astre Formula. No the iron duke wasn’t smooth, but it ran hard in the astre. There were many a small block that I toasted with the astre. Wish I still had it today as they are very rare (around 900 produced). Anyone know of one let me know!
I still have a ’77 Pontiac Astre Formula Safari Station Wagon… 2.5L Iron Duke, B-W T50 5 speed tranny with overdrive 5th… factory positraction…
The engine is smooth cruising up to about 85 MPH or so… seems like it will go about 100-110 MPH…
I just bought it for the 5 speed tranny to use in my MG Midget, but fell in love with it and kept driving it…
It seemed to get really good MPG for the ’70’s… One day I looked in the manual and was surprised to see it rated at 28 MPG city and 34 MPG hiway… so no wonder…
It seemed to be cammed to torque peak right around 55 MPH… presumably for good MPG at that speed… and it had a progressive 2 bbl. Weber carb. licensed to be built by Rochester? Carter? I’d have to look… small primary barrel, larger secondary barrel… kinda like half a Q-Jet 4 bbl….
With no timing belt (They failed around 50-70K in Vega engine) and no timing chain (they fail at 150-200K) and HEI electronic ignition, it is extemely reliable…
By ’77, the H-body had been modded for V6’s and V8’s in other versions… they had a proper crossmember under the engine, the HVAC hoses/boxes had been modified to clear wide V engines… the rear end had a torque arm like a Camaro, Firebird, Buick GNX… coil springs at all 4 corners…
I also have the EFI Iron Duke 4 w/ 5 speed in my ’85 Fiero… it’s not real fast, but doesn’t seem underpowered in normal driving… very smooth and quiet at hiway speeds…
My Brother had a 1976 Sunbird. 3.8 Liter and 5-speed. The backseat folded down so, lack of a hatch wasn’t bad. Hell of a car to be 6 foot plus, in the backseat for 8 hours. It would get 38 mpg @ 55 mph in 5th gear.
I have long assumed, but have not been able to confirm, that the Iron Duke was so named to make clear it was, well, made of iron, and thus not that awful melting easily-scratched aluminum-block Vega engine you’ve heard all those awful things about. But does anyone have a definitive reference to how/why it was so named, and who was responsible?
The Duke of Wellington, victor of Waterloo, was known as the Iron Duke. I’m sure he drove Pontiacs.
The first time I ever heard the “Iron Duke” name for that engine was in the text of one of the major automotive magazine articles of the late-’70s.
This was decades ago; I don’t remember which vehicle they were reviewing; and I certainly don’t remember the exact wording–but–I have the impression now that they were saying that the “new” engine in the vehicle was based on the “Iron Duke” from the Chevy II; as if the 153 was the original “Iron Duke” and known as such during the production life of the 153. (The 153 was never called an “Iron Duke” around me…) But this is a very fuzzy memory. I hope someone stumbles onto that article for some measure of confirmation.
Astre sales were very sluggish, but it had to do more with the astounding success of the Sunbird. If you look at Sunbird production figures, they go up dramatically each year, the last year of 1980 had the highest production. Customers just chose the Sunbird over the Astre.
“The Iron Duke was a Pontiac engine, derived from the 301 V8, with which it shared some of its architecture.”
The Iron Duke shared almost nothing with the 301. Bore and stroke numbers, and a connecting rod or something like that. The “architecture” was not at all based on the Pontiac V8. THAT rough-and-tumble engine was the “Half-a-389” Tempest Slant 4.
The Iron Duke also wasn’t a “Pontiac” engine. The basis was the Chevy 230 Inline Six from the early ’60s; which was then robbed of two cylinders to make the 153 Chevy II four-popper. The 153 was discontinued for automotive use in…’72 perhaps. A year or two later, GM of Brazil was selling the repackaged/reworked 151 which didn’t come to the USA until 1977, and Pontiac stole the credit for it. The early Iron Dukes would accept the longer-stroke Chevy 153 crankshaft if you installed custom pistons. Same timing gears, same non-crossflow head.
Over time, every single part in the entire engine would get revised, maybe multiple times. The Iron Duke had over 200 design changes in the course of it’s service life. GM never did manage to make a decent engine out of it, but they did make hundreds of thousands of crappy ones.
Buddy of mine had a ’77 Astre. Thing detonated like crazy. Got recalled for that. They slapped a thicker head gasket under the head. Dropped the compression, reduced power even more. Didn’t do much for the detonation. Still pinged like mad.
Another friend–an automotive machinist by trade–had an Iron Duke in an S-10. Of course, it was a turd. He rebuilt it with Big Block Chevy rocker arms, pushrods, and an Ultradyne-brand aftermarket “hot-rod” camshaft, which did little for the roughness but really perked-up the power. He blew the head gasket every time he drove out of City Limits until he found a coolant hole in the head that didn’t match the cooling hole in the head gasket and block. Once he modified the head to correct the alignment of the water passage, it became a reliable engine.
The Iron Duke was one of the worst GM engines since the Copper Cooled; rivaled only by the HT4100.
You’re right. Since I wrote that a few years back I’ve done a bit of research on the Iron Duke, and yes, it was essentially an evolution of the Chevy 153. Pontiac did a lot of misleading PR at the time to try to make it seem like it was somewhat more original than it really was, and I regurgitated some of that.
They did use a few internal parts in common with the 301, where possible, to save money. And there were quite a number of changes made, many minor, some more significant. But yes, one can drop in a 153 crank and some other parts.
Iron Duke, with no timing belt or even chain, was one of most reliable engines ever made!
It also got a Pontiac bellhousing…
Iron Duke 4 and Pontiac 301 V8 brought good MPG back to GM in 1976 !!!
Still have one in my rare ’77 Pontiac Astre FORMULA Safari (kammback) Station Wagon…
The Iron Duke had timing gears for a good share of it’s life. Changing to a timing chain in ’91 was one of the 200+ revisions of it’s later life.
The Duke started-out with a Chevy bellhousing, and ended up with the small-pattern also used on the 2.8L, 3.1L, and 3.4L V-6. I’m not aware of it EVER having a “Pontiac” “BOP” bellhousing.
The Duke did a wonderful job of breaking it’s own head-bolts, though.
Mama said if you can’t say something nice, keep your yapper shut. Something nice: “I’ve never known an Astre rain gutter to fail.”
The “Pontiac Ashtray” moniker reminds me: what’s a French smoker’s favourite type of halogen headlight bulb? H13! (If this makes no sense because you don’t speak French, go put H13 in Google Translate and hit the speak button.)
But seriously, though, I have to think it might be best not to name cars Astre, Astra, Aspire, or anything else that starts with “ass”.
How about “Aston”?
You’ve noted how the Astre wagon and the Vega Kammback didn’t really go away in 1978 and how the wagons were re-badged as Sunbirds and Monzas respectively for the 1978 and 1979 model years.
Less well-known is that there were a small number of 1978 Sunbirds and Monzas that used the Astre/Vega hatchback body-shell. I would guess that they were built to use up leftover auto bodies.
You can see a picture of the 1978 Chevrolet Monza “S” Hatchback using the Vega hatchback body in a sales brochure at the OldCarBrochures.com website. I don’t seem to be able to leave a link to the website but if you go there, you can see a picture of it in the brochure listed as “1978 Chevrolet Monza Brochure 2”.
I can’t find any documentation on the internet that the Astre-based Sunbird Hatchback actually existed, but I do recall seeing one at my local Pontiac dealer in 1977 or 1978. It used the same front-end clip as the 1978 Sunbird Sport Safari wagon.
http://oldcarbrochures.com/static/NA/Chevrolet/1978_Chevrolet/1978_Chevrolet_Monza_Brochure_2/1978%20%20%20Chevrolet%20Monza-12.jpg
My mother had a 75 Astre wagon. Other than the absolutely horrible engine, it wasn’t too bad for what it was. It looked good and held together till the end but that engine was always a problem with oil leaks, burning oil and 4 replaced radiators.
She got rid of it just in time. When she parked it at the dealers lot to pick up her new car, the engine seized completely with a spectacular bang with smoke and steam pouring out everywhere. Still she got an $800 trade in on it in 1981.