"The winningest 4 cylinder!" LOL's.

A friend of mine did a deep dive into the ID/Tek4 and dug up THIS ARTICLE, which, initially makes it sound like the ID/Tek4 was an overlooked engine with mad power potential. Yeah, sure...it had some limitations b/c it was designed for fuel economy and low cost production....but you get into Pontiac's SD catalog, and you can really unlock the hidden potential in this engine!

Then, they get into some details and you learn that:
"The lightweight crankshaft becomes structurally unstable above 5000 rpm and may fail under repeated abuse. Fragile connecting rods and pistons designed for low-speed operation are also prone to failure at high engine speeds, and the stock cylinder block doesn't have the rigidity or strength to withstand substantial power increases."

So, the head is junk, the crank is junk, the rods are junk, and....the block is junk. Yeah...."that engine" is winning ALL the races! 🙄

They "showed off" one version, which had the SD block, aftermarket crank/rods/pistons, SD head....so a completely different engine...and it made 205hp (GROSS, I'm guessing) in a Fiero. O.K. 205hp in a 4 cylinder Fiero should go pretty good. Car was pretty light @ ~ 2500 lbs? Thing ran 14.6@96 dudes!! We got stock 3rd gens that run that number! LOL, I say.

The article is akin to saying that:
"Yeah, sure...the LG4 had some limitations b/c it was designed for fuel economy and low cost production....but you get a Dart tall deck 4.125" bore block, Callies crank/rods, forged pistons, AFR heads, and you can really unlock the hidden potential in this engine!"

Anyway, I laughed. Maybe you will too.

 

LOL !!! ...

 

I can't imagine there are many iron duke 3rd gens left. It would be interesting to know how many.

I work for USPS and believe it or not some of the early LLV mail trucks still have them.

 

I got a good laugh from it too. This was my favorite part about how a special camshaft, different head, valvesprings, TBI, modified intake, header, and special chip:
" These modifications will make your stock 2.5-liter 4-cylinder competitive with the 2.8-liter V6 found in the Fiero GT, Firebirds, and S-10 pickups, but you should run a rev limiter set to 5000 rpm."

Lol. "Competitive" with a stock 2.8, but definitely limit rpm to 5k so the thing doesn't self destruct.

 

One of those magazine articles designed to make the unfortunates who got stuck with a LOSER, feel less ... of ... the reality they're now living in. Fantasy land and self-pleasure. Maybe even a bit of loafing the donkey or even buffing the bishop built into it.

That motor was a POS from the start. It was half of the absolute worst engine Pontiac ever "developed"; the 301. Total POS. Cutting it in half was even worse. Kinda reminds me of an old International Scout I had at one time... one of the TOUGHEST 4WD vehicles EVAH, butt it had this ... STUUUUUUPID ... 4-cyl, where it looked almost like the V8 block it was based on, with a plate cast over the empty cylinders. I'll give GM that: at least they turned it upright instead of leaving it at 45°.

At some level, CID always wins. In some ways it doesn't matter how you get around to achieving CID of air/fuel burned and converted to mechanical power; whether it's bore x stroke, or better induction system, or turbo / supercharging, or what. Some combination of HOW MUCH AIR/FUEL can you burn, and HOW MUCH of that energy can you convert from heat into mechanical motion, and HOW MUCH do you lose to the various inevitable losses (pumping, inertia, mass, etc.), and HOW LONG will it last doing it. That piddly "iron puke" POS LOSES on ALL POSSIBLE dimensions with the possible exception of weight, and THAT only in comparison to an all-cast-iron V8. As the Europeons and misc Asians and Ozzies will ask, how the hell can you take a 5.7 liter V8, and get ONLY 160 HP out of it. [mr_spock]Humans.[/mr_spock]

What a EFFFFFFFFFFING JOKE. Glad it wasn't some n00b that had accidentally bought one and posted here all about "I just bought this and I found this magazine article and does anybody know where I can order these parts from" just destined for a MAJOR disappointment.

 

The SD program for those was no joke really.

 

OK ...

How so?

 

Yeah, not to be an a-ho' but how so?

If you buy a block, crank, rods, pistons, head, and then custom fab all the ancillaries.....then run 14.6/96 in a 2500 lb car....how's that not a joke?
IDK...it doesn't seem too good, to me....


I wonder how the old, 60's "Trophy 4" would respond to mods, in comparison to this example?

 

About the same...

Might run at/near the top of its class in some kind of CID vs weight situation (like your 4-cyl in a 3200 lb min car goes 15.3 butt my 4-cyl in a 3200 lb car goes 15.1), butt in ANY KIND of heads-up racing, it'd get SMOKED. Not to mention, HOW MANY SUCH races can it run. Back when I was building motors, admittedly it's been awhile, one of the problems racers had, was the expense of a new motor every (x) races; I made a point of making sure mine could go (x) + 3 or whatever. In those lower slower classes like that, that nobody in the stands gives a crap about (they all go buy hot dogs and beer while those non-entertaining things are ooooozzzing along and wasting the track's time), not having to buy a new motor as often, can make the difference between going fast ONCE and setting some kind of a dyno / Engine Masters record, and running for a season championship with 12 or 16 or 20 race weekends IN THE REAL WORLD with 3 to 6 runs per race and winning a $100 purse with a $7500 motor. That was back in the day before buy-backs though so maybe nowadays it's possible to minimize how many times you have to run it in one weekend and thereby limit how many motors you need per season. Iunno anymore, that kind of stuff long since became NOT fun for me anymore.

In any kind of claimer class it wouldn't last any more than one whole race if it EVER won. Then the stoooooooooje that bought it would be saddled with loooooozzzzzing races from then on.

 

Probably. I was thinking that the Trophy was a 389 chopped in 1/2 (yeah, dumb), but as such, perhaps you could run off the shelf cams, the 6X head? you got the regular deck height....and end up with 1/2 -a-good-389. Which I guess ain't that great, and you're back to ~200hp. I doubt the cast rods in that engine can take much more than 5k RPM, too.

 

May I choke the chicken now? Or must I wait for ... something?

Ya know, I actually saw one of those POSs in a junkyard one time. I was like, W...T...F?. It was kinda like watching a slow-motion train wreck... you know you're gonna be SICK (and I was), butt you just can't look away until it's over. I've been able to exercise better self-discipline about the 6-cylinders in these cars though. Can't say I've ever really seen one of those.

 

"Iron Duke: Unleash the hidden potential!!"


No thanks; I'm good.

 

I mean, if you can't handle all that powa...... lol

 

Over 20 years ago Honda's 2.4 liter normally aspirated 4 cylinder produced 245 hp with quarter mile times as low as 13.9 in a 2,800 lbs car with excellent reliability, stock from the factory.
I really enjoyed mine but ended up trading it in to a local Chevrolet dealership (that also owned a Honda dealership across the road) for a '71 Z28 that I just had to have.

 

The only thing that the Pontiac POS has in common with that, is the # of cyls. Which partly explains why the Honda motor put out 2½ times the power that the crappy Pontiac did. Whatever a Honda did, has no bearing whatsoever on that other POS.

 

Unlocking the hidden potential of getting an entirely different engine.

This is kind of like the old book how to run 11s in your F-body and 20 pages in it says get yourself a bigger engine LOL!

 

I think everyone is totally underestimating the potential of these little engines. At half the weight and all the durability of the 301 it's a win/win. Think about it. If one of these was built for turbo power and had two small turbos for instant spool. Then using a dual disk clutch coupled to a t5 coupled to a stock rear w a posi and some slicks. It would rip. I think the only questions here should be how would you fit the ac compressor with twin turbos and how much fuel will it sip while blasting down the quarter mile in 10.5. Wheels up!!!

 

As someone who drives a 2.8 daily and has looked into almost every way to make it “fast”, I highly doubt anyone here is underestimating the Duke. I can’t imagine anyone blowing that much money on an engine just for it to be “competitive” with the v6.

 

Gonna quote this so it doesn't get missed:

"The lightweight crankshaft becomes structurally unstable above 5000 rpm and may fail under repeated abuse. Fragile connecting rods and pistons designed for low-speed operation are also prone to failure at high engine speeds, and the stock cylinder block doesn't have the rigidity or strength to withstand substantial power increases."

 

Iron Duke unleash the hidden power to get to 125hp.

What a joke.

 

At one point I had three Fieros. Two of them had the 151- inch four-holer. I can attest to the fact that the design was NOT a 300lk mile engine like so many SBCs turned out to be.

 

Vader, I believe you.

 

Just wanted to revive this thread, haha... can't help myself.

My daughter just went through totally rebuilding her Iron Duke... so I've fortunately / unfortunately spent the last year and a half working on a duke every weekend (or watching her do it).

The Super Duty 4 is really a totally different engine from the Iron Duke. Obviously, every part is interchangeable with each other, which was intentional. I think... I THINK this was required for the purpose of racing. When you put the Iron Duke up against a Super Duty 4, the bolt locations, everything is in the same place, but the block and wall thickness is twice the Iron Duke.

I think it's important to remember "the time." First, I have no idea why an Iron Duke ever ended up in a Third Gen... I have no idea what they were thinking. In a Fiero, the Iron Duke, even with a decent 5-Speed manual transmission, was like a 9 second 0-60 car. In a Third Gen, it must have been brutal.

The Super Duty 4, though... was pretty decent performance for the early 80s. Gotta remember that it's all smog-era technology. There were essentially three specifications of Super Duty-4 motors... the 2.1L (~200hp), the 2.7L (230hp) and the 3.2L (280hp). I think the only one you could use in a normal Iron Duke block was the 2.1L parts... there just wasn't enough meat on a normal block for 2.7 or 3.2L motors.

These parts are unobtainium now, but the only people who buy them now, is for the nostalgia / period correct nature of it, since you could order these parts at the local Pontiac dealership.

For that matter... (quasi-related), there was an all aluminum and reinforced 3.4L V6/60 block that is the same as the one in the 93-95 Camaro / Firebird, but a thicker block, and made of aluminum with steel sleeves. I WISH I had bought one of these when I could. I'd pay cash right now... but some aeronautics company bought them all up and used them as small airplane engines (which makes no sense), so they're basically also unobtainium.

Anyway... the Super Duty 4 was a big deal back in 1984... and all these high performance ones were carbureted. Offenhauser, Edelbrock, and Holley all made intakes for them.

By the late 80s though, it just didn't make any sense with the new Quad-4 that came out in 87... which was pretty great... became the TwinCam, and more or less replaced by the EcoTec.


Anyway... I think it's just important to consider "the time." My 81 TransAm that I had many years ago had a 301 Pontiac V8 in it, which quite literally made 140 horsepower.

 

My first HS car was a '83 Iron Puke 4spd Camaro Sport coupe. That car was ridiculously slow. With no OD, it was revved out by 65mph and felt like it was going to explode at highway speeds. I intended to small block swap it, but I let a friend drive it, and at the time he apparently decided it would look better wrapped around a Ford Thunderbird.

 

At least it was a manual!

 

The only people who would actually "need" the iron duke or any of those 4 cyl engines is if you're racing in a class that gives you an advantage with a power to weight ratio.

For street use, even a basic V6 would be a better option. That's also why the 4.8L and 5.3L LS swaps are popular. Gives good power without all the extra weight although the 6.0L is just one more step up.

 

Again though, that's what I was saying... the Super Duty 4 only really made sense as a performance build back in the early 80s. It gets trashed a lot... but it produced pretty sick power for a 4 cyl back then. It doesn't make sense at all today, but the 4.8 and 5.3 LS weren't available in 1984.

As far as engine swaps go, I don't even know if I would want an LS in a Porsche 944, I'd probably just go with a 3400 SFI and a Turbo. So many more options today for engine swaps. The SD4 is just a thing of history / the past... it was awesome at a time when emissions and fuel economy were the dominating factors, and V8s put out 130 horsepower...

 

Finally - There is the key. Flint was scrambling for a small engine to power wrong-wheel sidewinders to attempt to meet emissions and CAFE goals. Someone in the back storage shed stubbed their toe on an old pallet with this relic of the Johnson administration on it and had an idea. The rest was history.

One of the Fieros I had an example of the 151 which got more of my attention than it deserved. There was port work, valve work, springs, intake matching and massaging, exhaust cleanup, and all for negligible gain. I can't imagine that GMPD stayed very busy filling orders for any "go-fast" parts for these. I know that the bottom ends were weak, blocks were unstable, and rotating units were probably more air space than iron. The engines were light enough to probably make a reasonable stab at being a generator, trash pump, or small marine engine where RPM would be governed, or a utility vehicle, maybe.

Two was more than enough for me.

 

Haha...

I had my daughter rebuild one from scratch so she could learn engine mechanics...

 

If you're doing a swap and don't really care what goes into the car, my 2019 F150 has a 2.7L TT V6 and has more power and torque than my 91 454ss ever had and gets much better fuel mileage. The 454SS however was a lot more fun to drive.

 

Old Superbird Superduke article. 3.3L Stroker built from the SD catalog making 100hp/L

https://drive.google.com/file/d/0B0g...9o_nJnCuiGAPMw

 

That's the same motor they are putting in the Bronco also. You can get a 3 liter version of it with the Raptor Bronco.

We just got a new Bronco 2-door, but it has the 2.3L Turbo... and in race mode (haha), it actually puts out 300 horsepower, which is just crazy. We have a Solstice GXP that my daughter uses to just beat around in, and it's got a 2.0 LNF Turbo with 260hp. Turbo just seems like the way to go... but I do really prefer NA, to be honest.

 

that 2.3l eco boost is a detuned version of what was in my Focus RS. Which was 350hp/350lbft at the crank. And with a conservative 93 octane tune was putting 360whp and almost 400lbft to the ground through the AWD system.

Turbos make torque.

would have made a fun swap in a Thirdgen. The 2.0L LNF out of the Solstice/Sky/Cobalt would also have been fun. Cobalt SS/TC was once the fastest FWD car around the ‘Ring.

But then again. Many of the modern I4s with turbos aren’t really lighter than a straight up aluminum LS swap.

 

"The 2.0L LNF out of the Solstice/Sky/Cobalt would also have been fun. Cobalt SS/TC was once the fastest FWD car around the ‘Ring."

Seems like that's been the case for a while too. I remember in the late 90s and early 2000s, you had the 2.4 TwinCam with the 5-Speed Getrag. Mostly average in a full bodied Grand Am sedan or Oldsmobile Alero. But in the Cavalier / Sunfire, they were running mid 14s all day long with the 5-Speed. GM sold a SuperCharger kit that bolted right onto it, and brought the power up from 175hp (kind of understated) to 225hp... and they were high 13 cars all day long.

The power though from those turbos is wild.

The thing I dislike about the Bronco... when you floor it, it sounds like you've got a Pontiac 455 Super Duty with an open element air cleaner and glass packs. It sounds awesome... until you realize that sound is ONLY coming from the inside of the car, and not actually the exhaust. Ford pipes in engine sounds to create a more visceral experience.


All the talk of 4 cyls... honestly man... I have this in a storage unit, where it's been sitting for 14 years:



It's a 1969 Oldsmobile 455 big block, punched out to a 468. I personally spoke to Joe Mondello on the phone when I ordered the parts from him, back when he was still alive, that's how long ago it was. I ordered a special grind camshaft... roller rockers with full fulcrum rockers, I went nuts on this engine. I had the whole thing rebuilt by Astral Engine rebuilders. JUST the machine work and balancing cost me $7k back in 2009. The engine came from a full sized station wagon, and it had "C" heads, which were ground out to (at the time) was an insane 2.07:1 intake and 1.72:1 exhaust valve.

Based on how it was spec'ed out, it was supposed to put out nearly 600 foot pounds of torque, and 480 horsepower.

I was going to put it in my 1981 Pontiac TransAm, but then ended up selling the car when my daughter was born, along with a bunch of other cars. I didn't need the money, I just wanted to focus on being a dad, and I don't regret the decision. I put that engine in storage when I had to move for work in 2011, and it now sits in a storage unit, where it's been for 15 years. I filled the engine with oil, like, completely... and I still crank it by hand every couple of years to make sure it's ok. It's wrapped in plastic with a desiccant bag, but I think if I ever take it out of storage, I'm going to have to re-do all the seals except maybe the head gaskets.

But man, I spared no expense on this motor... it has TRW forged pistons, forged rods, a hardened crank... and I had the entire rotating assembly balanced to within half a gram. The machine shop used to be dedicated to making / building racing engines at the time. They even ported and polished the heads. The thing is a total beast... I just don't have anything to put it in. Once my daughter is in college though, I'm going to work on my projects. Right now... it's all her time and her projects.

 

Anyone remember Smokey Yunik with his hot air something iron duke 84 fiero making 800hp. It had a tendency to brake parts though.

 

Sorry to spam with my daughter's videos... but you guys keep triggering me, haha...

The Smokey Yunik Fiero is now located near Gainesville, FL... at the Don Garlits Museum of Drag Racing.


at the 8:55 mark in the video.

 

I remember that pile. I also remember that it wasn't anywhere near 800 hp. Or even 1/2 that. EDIT: Or even 1/4 of that.

With 15 lbs of "heated air" (aka, "boost")....
"the production 151-cubic-inch (2.5 liter) Iron Duke 4-cylinder, the car now gets more than 50 miles to the gallon, develops 250 hp and 230 ft.-lbs. of torque, runs more smoothly than any 4-cylinder you've ever experienced, starts and idles smoothly and cleanly, has no computer controls, passes federal emissions standards, and oh yes, it'll accelerate from 0-60 mph in as little as 6 seconds flat!"

Unfortunately....0-60 in 6 seconds, 250 hp and 2600 lbs do not all align.

 

I think what was the unique aspect of it, is that it would vaporize the fuel into a steam by super-heating the intake air from the exhaust (which was also turboed as you said), and that helped atomize the fuel delivery. Faye Hadley is good friends with one of Smokey's protégé's, and they rebuilt Smokey Yunick's Fiero (the one in the museum), and also the one he did on a Dodge Omni.

She explains it here in this short:
It runs extremely lean, but gets perfect AFRs (apparently) when it's under load.

This was the guy's latest update:
It was late November, but he apparently fell off a ladder and has been injured, and he hasn't taken it to the track yet. But apparently he's looking to take it to a track in the next few weeks. I guess we'll just have to see. I do wonder why there are no videos of any of these hot vapor cars running down a track?

For the Fiero, those early non-GT Fieros weighed a little over 2500 pounds. The quickest one is either the 85 Fiero GT with the 3.65:1 4-Speed Muncie and the 2.8 V6/60, or the 1988 Fiero Formula 5-Speed with the 5-Speed Getrag and 3.61:1 ratio and the same 140hp V6. Generally, they run low 7s in the 0-60 with most conditions being positive (good air temps, sea level, blah blah). They are generally mid to high 7 second cars, with the lofty GT ones or ones with all the options in the low 8s, and automatics almost into the 9s. I'd say probably the quickest stock Iron Duke powered ones would have to be like the 87 Coupe with the DIS ignition and the 5-Speed, which runs a low 9 second 0-60 on a good day. A loaded automatic Duke is like in the high 10s. The 5-Speed in the 4cyl though is an Isuzu, which cannot handle 250hp, so my guess is he probably would have had to swap it out with a 4-Speed. I'd have to say though, 15 pounds of boost (???) you can get anything to go fast.

I have a 2007 Pontiac Solstice GXP that's pretty quick. It has the 260hp Ecotec 2.0, and the 0-60 with the Aisin 5-Speed is 5.6 seconds according to Road & Track. The GXP weighs anywhere from 3,100-3,200 pounds, so a flat 6 in the 0-60 with 250hp in a 2,500 pound car doesn't seem unrealistic.

I just wonder, if the hot vapor design is so good, why didn't manufacturers use it?

 

1. Exactly. Which is why there is nothing special about the "hot air engine"....and why the "boost" is only a function of intake temps...is a bit misleading.
2. 250hp is 10lb/hp....that should do 0-60 faster than 6 seconds. Your GXP is 11.9 lb/hp and as you stated, does it in 5.6 with a worse power to weight ratio.
3. I wonder that, too. That is a pretty strong clue as to the real benefits of the concept.

 

Because the OE's had invested so much in FI, OBD and the catalytic converter.

 

I don't think that's why. At that time they needed all the help they could get....if the idea met all of the criteria, and worked, they'd have implemented it. The carbs they already had, a turbo (oh, wait, excuse me....an "homogenizer"...."it's not a turbo!") and some plumbing would have been much cheaper than cats, ECMs, harnesses and EFI.

HRM, bless their hearts, loves to throw out articles with magical solutions....that never take hold. This pipe dream, they did an article on a big hp Poncho that "passed emissions" w/no EGR, no Cat and no engine controls, and I remember "The 350 Chevy should have built"....on and on. They're interesting the ponder and some of the principles have some merit...but you can bet your azz that if the OEM's could have gotten an engine to meet all criteria with a couple extra parts...while improving fuel economy and power? They'd have done that instead of TBI....or whatever.

 

My guess is the hot vapor engines couldn't endure adverse conditions over time. I would imagine running anything at the hairy edge of lean is a knife balancing act, and as soon as those carburetors or anything else in the complexity of hot vapor fuel delivery goes out of tune, it could easily cause abnormal wear at best and catastrophic failure at worst.

 

I wonder if / how they addressed NOx emissions with the tech of the time (having claimed it "meets emissions")? I guess he's saying it's lean without creating the kind of combustion temps (not melting pistons) we would associate with an 18 or 19:1 mixture. That might explain it in theory.

I'll be interested to see this Omni run. Not doubting, but would like to see it in action. Would also like a little more detail on how this is all achieved. Details were very much lacking "back in the day" IIRC.