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Non-Road Boards => Off-Topic => Topic started by: kernals12 on April 14, 2023, 11:36:11 PM

Title: What if the Wankel Engine had worked?
Post by: kernals12 on April 14, 2023, 11:36:11 PM
This video got me thinking...


Of all the "better mousetrap" engines to be devised over the years, the Wankel has been, by far, the most successful. It is the only one that's made it to mass production. And for a time in the early 1970s, it seemed destined to replace the mighty Otto cycle. The engine is smooth, compact, lightweight, and has very few moving parts. But there were lots of problems that turned out to be insurmountable with the technology available at the time. The problems stemmed from 2 sources
1. Imperfect sealing caused by temperature distortions between the different chambers
-Sometimes the apex seals wouldn't do their job and they would allow combustion gases to escape between chambers, causing high emissions and wasted fuel
-Sometimes the apex seals would dig too far into the combustion chamber walls, causing rapid wear and lots of maintenance issues
2. A Long combustion chamber
-With a high amount of surface area, this would "quench" combustion, leading to high HC emissions and inefficiency.

But, 40 years later, Mazda managed to perfect clean and efficient low temperature combustion, effectively solving those problems.

So now I want to imagine if somehow, they figured out how to implement that back in the 70s.

The automotive world would be very different. Cars would be a lot lighter and with better weight distribution, they'd handle better. Mid-engined layouts would probably be more common because the compact Wankel would allow more luggage space. I would also like to think that smaller cars would be more popular. Why? Because as it is, the inline 4 cylinder engines (occasionally 3) that power those cars in our world are very unrefined due to the inherent lack of balance that engine layout suffers from. But a wankel engine is inherently smooth and means even a crappy subcompact would be as pleasant as a V12 powered luxury sedan.
Title: Re: What if the Wankel Engine had worked?
Post by: formulanone on April 15, 2023, 12:12:22 AM
One of the arguments against the Wankel was a lack of low-end torque, at least on the performance side. So it might have been okay for a light pickup truck, but even Mazda gave up on that after a short spell in the mid-1970s. Similar to a turbine engine, the spool-up of power was a little slower at low RPMs.

Other manufacturers never really gave it a serious look, perhaps looking more to aerodynamics and lighter weights to offset fuel consumption; redesigning all-new powerplants do not occur as quickly as new models. A manufacturer might only put out an all-new engine design every 5-10 years and stick with it for 15-20+ years with a little development every few model years to keep up with competitors. So a radical all-different approach would have been a massive expense at a moment when many auto manufacturers were looking at middling profits and an uncertain future, with research and development possibly taking 10 years for a generally reliable unit.

Turbocharging it definitely gave it a big advantage in motosports, where its smaller displacement could be an advantage in formulae with sliding-scales of minimum weights to overall displacement, used frequently in sports car/prototype racing (i.e. bigger engine = increased minimum vehicle weights).

In 1991, a four-rotor Mazda 787B was able to win 24 Hours of Le Mans, its shining moment, though the three-car Jaguar team seemed to make a few more mistakes while leading. That R26B four-rotor engine is spectacularly loud.

Title: Re: What if the Wankel Engine had worked?
Post by: kernals12 on April 15, 2023, 10:53:05 AM

Quote
Other manufacturers never really gave it a serious look, perhaps looking more to aerodynamics and lighter weights to offset fuel consumption;

Okay. That is so, so wrong. In the first half of the 70s, many automakers were convinced the piston engine was about to become obsolete. NSU was the first to put it in a production car and when they got bought by VW, the latter looked into it. Mercedes built a mid engined prototype supercar around the Wankel. Citroen built one for a sporty version of their GS and were planning to use it on the luxurious CX. They even built an entire factory for it. The failure of that engine was a key reason for their bankruptcy in 1974.

And we haven't even gotten to General Motors. In 1972, John DeLorean, then VP of Car and Truck production, said he believed that in 10 years, the company would be almost entirely Wankel powered. They were planning to put their first Wankel in a sporty version of the Chevrolet Vega called the Monza, and AMC was planning to buy that engine to put in their Pacer. The cancellation of the engine forced AMC to shoehorn in their 3.8 liter 6 cylinder engine.

So yeah, Mazda was far from the only automaker to give the Wankel a serious look.

Title: Re: What if the Wankel Engine had worked?
Post by: mgk920 on April 15, 2023, 12:47:20 PM
Quote from: kernals12 on April 15, 2023, 10:53:05 AM

Quote
Other manufacturers never really gave it a serious look, perhaps looking more to aerodynamics and lighter weights to offset fuel consumption;

Okay. That is so, so wrong. In the first half of the 70s, many automakers were convinced the piston engine was about to become obsolete. NSU was the first to put it in a production car and when they got bought by VW, the latter looked into it. Mercedes built a mid engined prototype supercar around the Wankel. Citroen built one for a sporty version of their GS and were planning to use it on the luxurious CX. They even built an entire factory for it. The failure of that engine was a key reason for their bankruptcy in 1974.

And we haven't even gotten to General Motors. In 1972, John DeLorean, then VP of Car and Truck production, said he believed that in 10 years, the company would be almost entirely Wankel powered. They were planning to put their first Wankel in a sporty version of the Chevrolet Vega called the Monza, and AMC was planning to buy that engine to put in their Pacer. The cancellation of the engine forced AMC to shoehorn in their 3.8 liter 6 cylinder engine.

So yeah, Mazda was far from the only automaker to give the Wankel a serious look.

Patent law issues?

Mike
Title: Re: What if the Wankel Engine had worked?
Post by: hotdogPi on April 15, 2023, 12:58:35 PM
Patents only last 20 years. They've expired by now.
Title: Re: What if the Wankel Engine had worked?
Post by: formulanone on April 15, 2023, 02:10:51 PM
Quote from: kernals12 on April 15, 2023, 10:53:05 AM

Quote
Other manufacturers never really gave it a serious look, perhaps looking more to aerodynamics and lighter weights to offset fuel consumption;

Okay. That is so, so wrong. In the first half of the 70s, many automakers were convinced the piston engine was about to become obsolete. NSU was the first to put it in a production car and when they got bought by VW, the latter looked into it. Mercedes built a mid engined prototype supercar around the Wankel. Citroen built one for a sporty version of their GS and were planning to use it on the luxurious CX. They even built an entire factory for it. The failure of that engine was a key reason for their bankruptcy in 1974.

And we haven't even gotten to General Motors. In 1972, John DeLorean, then VP of Car and Truck production, said he believed that in 10 years, the company would be almost entirely Wankel powered. They were planning to put their first Wankel in a sporty version of the Chevrolet Vega called the Monza, and AMC was planning to buy that engine to put in their Pacer. The cancellation of the engine forced AMC to shoehorn in their 3.8 liter 6 cylinder engine.

So yeah, Mazda was far from the only automaker to give the Wankel a serious look.


Wake me when it hits production is my mantra. Outliers and un-drivable museum pieces don't move the needle.

Yes, other automakers did tests but nobody did more than a few concept cars, a few tests and the end result of that was approximately a dozen road-going cars that weren't Mazdas or NSUs.

Title: Re: What if the Wankel Engine had worked?
Post by: Max Rockatansky on April 15, 2023, 02:36:05 PM
Given how inefficient and how many problems the recent RX-8 had there was no chance the Wankle was going to be anything but niche during 1970s.  GM invested heavily trying to make the engine viable (particularly for the Corvette) and couldn't pull it off.
Title: Re: What if the Wankel Engine had worked?
Post by: kernals12 on April 15, 2023, 02:39:36 PM
Quote from: formulanone on April 15, 2023, 02:10:51 PM
Quote from: kernals12 on April 15, 2023, 10:53:05 AM

Quote
Other manufacturers never really gave it a serious look, perhaps looking more to aerodynamics and lighter weights to offset fuel consumption;

Okay. That is so, so wrong. In the first half of the 70s, many automakers were convinced the piston engine was about to become obsolete. NSU was the first to put it in a production car and when they got bought by VW, the latter looked into it. Mercedes built a mid engined prototype supercar around the Wankel. Citroen built one for a sporty version of their GS and were planning to use it on the luxurious CX. They even built an entire factory for it. The failure of that engine was a key reason for their bankruptcy in 1974.

And we haven't even gotten to General Motors. In 1972, John DeLorean, then VP of Car and Truck production, said he believed that in 10 years, the company would be almost entirely Wankel powered. They were planning to put their first Wankel in a sporty version of the Chevrolet Vega called the Monza, and AMC was planning to buy that engine to put in their Pacer. The cancellation of the engine forced AMC to shoehorn in their 3.8 liter 6 cylinder engine.

So yeah, Mazda was far from the only automaker to give the Wankel a serious look.


Wake me when it hits production is my mantra. Outliers and un-drivable museum pieces don't move the needle.

Yes, other automakers did tests but nobody did more than a few concept cars, a few tests and the end result of that was approximately a dozen road-going cars that weren't Mazdas or NSUs.
It got a lot further than almost every other engine tagged by Popular Science
Title: Re: What if the Wankel Engine had worked?
Post by: formulanone on April 15, 2023, 02:51:37 PM
Quote from: kernals12 on April 15, 2023, 02:39:36 PM
Quote from: formulanone on April 15, 2023, 02:10:51 PM
Quote from: kernals12 on April 15, 2023, 10:53:05 AM

Quote
Other manufacturers never really gave it a serious look, perhaps looking more to aerodynamics and lighter weights to offset fuel consumption;

Okay. That is so, so wrong. In the first half of the 70s, many automakers were convinced the piston engine was about to become obsolete. NSU was the first to put it in a production car and when they got bought by VW, the latter looked into it. Mercedes built a mid engined prototype supercar around the Wankel. Citroen built one for a sporty version of their GS and were planning to use it on the luxurious CX. They even built an entire factory for it. The failure of that engine was a key reason for their bankruptcy in 1974.

And we haven't even gotten to General Motors. In 1972, John DeLorean, then VP of Car and Truck production, said he believed that in 10 years, the company would be almost entirely Wankel powered. They were planning to put their first Wankel in a sporty version of the Chevrolet Vega called the Monza, and AMC was planning to buy that engine to put in their Pacer. The cancellation of the engine forced AMC to shoehorn in their 3.8 liter 6 cylinder engine.

So yeah, Mazda was far from the only automaker to give the Wankel a serious look.


Wake me when it hits production is my mantra. Outliers and un-drivable museum pieces don't move the needle.

Yes, other automakers did tests but nobody did more than a few concept cars, a few tests and the end result of that was approximately a dozen road-going cars that weren't Mazdas or NSUs.
It got a lot further than almost every other engine tagged by Popular Science

Nobody is denying that.
Title: Re: What if the Wankel Engine had worked?
Post by: kernals12 on April 15, 2023, 05:02:11 PM
Quote from: Max Rockatansky on April 15, 2023, 02:36:05 PM
Given how inefficient and how many problems the recent RX-8 had there was no chance the Wankle was going to be anything but niche during 1970s.  GM invested heavily trying to make the engine viable (particularly for the Corvette) and couldn't pull it off.

This would've been a gamechanger
(https://i.imgur.com/UgBopP2.png)
It would've allowed lower combustion temperatures and hence less heat loss to coolant and less thermal distortion of the rotors
Title: Re: What if the Wankel Engine had worked?
Post by: Max Rockatansky on April 15, 2023, 05:11:38 PM
Have you ever actually looked into a fuel economy of an RX-7 and RX-8? 

https://www.fuelly.com/car/mazda/rx-7

https://www.fuelly.com/car/mazda/rx-8

You like to throw out "game changer"  a lot in your threads but really seem to not comprehend technical challenges that actually occur/occurred.  The automotive world is full of supposed "game changers"  that usually don't pan out.  The Wankel engine did better than most, but it was another game changer that didn't pan out.
Title: Re: What if the Wankel Engine had worked?
Post by: kernals12 on April 15, 2023, 05:35:39 PM
Quote from: Max Rockatansky on April 15, 2023, 05:11:38 PM
Have you ever actually looked into a fuel economy of an RX-7 and RX-8? 

https://www.fuelly.com/car/mazda/rx-7

https://www.fuelly.com/car/mazda/rx-8

You like to throw out "game changer"  a lot in your threads but really seem to not comprehend technical challenges that actually occur/occurred.  The automotive world is full of supposed "game changers"  that usually don't pan out.  The Wankel engine did better than most, but it was another game changer that didn't pan out.
Yes, I'm well aware of the issues. I went into detail about them in the OP.
Title: Re: What if the Wankel Engine had worked?
Post by: Max Rockatansky on April 15, 2023, 05:45:47 PM
Actually you didn't list them all (more so didn't paint a full picture).  Wankel engines tend to produce peak power very high in the rev range.  In the case of the RX-8 it produced peak power at 8,500 RPM.  There is no way an engine running at 8,500 RPM (or consistently over 6,000) will be very fuel efficient, even if the car is lightweight.  Getting mileage in the high teens out of a 1.3L displacement engine is far from optimal. 
Title: Re: What if the Wankel Engine had worked?
Post by: JREwing78 on April 15, 2023, 08:28:34 PM
Mazda's still trying, this time as a range-extender: https://www.treehugger.com/mazda-electric-car-gets-rotary-range-extender-7099136
Title: Re: What if the Wankel Engine had worked?
Post by: LilianaUwU on April 15, 2023, 09:02:59 PM
If the Wankel engine had worked, there'd be more "Wanker engine" jokes today.
Title: Re: What if the Wankel Engine had worked?
Post by: Max Rockatansky on April 15, 2023, 09:07:17 PM
Quote from: LilianaUwU on April 15, 2023, 09:02:59 PM
If the Wankel engine had worked, there'd be more "Wanker engine" jokes today.

I often wondered sitting at car shows if RX-7 and RX-8 dudes told people they were going to "wank it"  when they were going out for a drive?  If I had a Wankel engine I probably would be saying that all the time.
Title: Re: What if the Wankel Engine had worked?
Post by: Takumi on April 15, 2023, 09:09:21 PM
Quote from: Max Rockatansky on April 15, 2023, 09:07:17 PM
Quote from: LilianaUwU on April 15, 2023, 09:02:59 PM
If the Wankel engine had worked, there'd be more "Wanker engine" jokes today.

I often wondered sitting at car shows if RX-7 and RX-8 dudes told people they were going to "wank it"  when they were going out for a drive?  If I had a Wankel engine I probably would be saying that all the time.

Probably too busy screaming at people who dared suggest they LS swap their cars.
Title: Re: What if the Wankel Engine had worked?
Post by: LilianaUwU on April 15, 2023, 09:12:14 PM
Quote from: Takumi on April 15, 2023, 09:09:21 PM
Quote from: Max Rockatansky on April 15, 2023, 09:07:17 PM
Quote from: LilianaUwU on April 15, 2023, 09:02:59 PM
If the Wankel engine had worked, there'd be more "Wanker engine" jokes today.

I often wondered sitting at car shows if RX-7 and RX-8 dudes told people they were going to "wank it"  when they were going out for a drive?  If I had a Wankel engine I probably would be saying that all the time.

Probably too busy screaming at people who dared suggest they LS swap their cars.
Everytime I hear about LS swapping, I think of this meme:
(https://i.redd.it/i0eel46yq2951.jpg)
Title: Re: What if the Wankel Engine had worked?
Post by: Max Rockatansky on April 15, 2023, 09:28:43 PM
LS swaps have been done to death.  It's always worth a tip of the cap to someone who uses a salvage engine or a crate engine from another manufacturer.  I'm also kind of bored with using modern fuel injection engines in older cars that had carburetors.
Title: Re: What if the Wankel Engine had worked?
Post by: Takumi on April 15, 2023, 11:00:27 PM
They’re boring, but I get it. The LS is small, can be bought for cheap, and has a huge aftermarket, so it’s easy to get them to make power. Just today at Cars & Coffee there were three LS-swapped non-GM cars I saw: a Nissan Sileighty (https://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Sil-180SX.JPG/1280px-Sil-180SX.JPG), which is a front end swapped 180SX or 240SX, a Subaru BRZ, and a Beetle.

Myself, I’d probably do a Honda K-series.
Title: Re: What if the Wankel Engine had worked?
Post by: SectorZ on April 16, 2023, 09:06:36 AM
Quote from: Takumi on April 15, 2023, 11:00:27 PM
They're boring, but I get it. The LS is small, can be bought for cheap, and has a huge aftermarket, so it's easy to get them to make power. Just today at Cars & Coffee there were three LS-swapped non-GM cars I saw: a Nissan Sileighty (https://upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Sil-180SX.JPG/1280px-Sil-180SX.JPG), which is a front end swapped 180SX or 240SX, a Subaru BRZ, and a Beetle.

Myself, I'd probably do a Honda K-series.

The YouTuber Rich Rebuilds LS swapped a Tesla S. Gave it the name Ice T.

https://www.thedrive.com/news/43394/worlds-first-v8-swapped-tesla-model-s-is-officially-on-the-road
Title: Re: What if the Wankel Engine had worked?
Post by: kernals12 on April 16, 2023, 10:41:06 AM
Youtuber gets an LS powered artificial heart
Title: Re: What if the Wankel Engine had worked?
Post by: SP Cook on April 16, 2023, 10:46:31 AM
The Wankel engine DID work.  It was killed by environmental extremists.  In 10 or 20 years, when you are puttering around in an electric go cart or forced back into city tenements for communal transit, don't let someone say that gasoline engines didn't "work".  They did.   
Title: Re: What if the Wankel Engine had worked?
Post by: kkt on April 17, 2023, 01:04:39 AM
Quote from: SP Cook on April 16, 2023, 10:46:31 AM
The Wankel engine DID work.  It was killed by environmental extremists.  In 10 or 20 years, when you are puttering around in an electric go cart or forced back into city tenements for communal transit, don't let someone say that gasoline engines didn't "work".  They did.   

It worked in the sense that you could power a car with a Wankel engine, but the ways in which it was worse than cylinders outnumbered the ways in which it was better.

Title: Re: What if the Wankel Engine had worked?
Post by: Scott5114 on April 17, 2023, 03:07:41 AM
Quote from: SP Cook on April 16, 2023, 10:46:31 AM
The Wankel engine DID work.  It was killed by environmental extremists.  In 10 or 20 years, when you are puttering around in an electric go cart or forced back into city tenements for communal transit, don't let someone say that gasoline engines didn't "work".  They did.   

I'll just let people say your ridiculous prediction didn't work instead.
Title: Re: What if the Wankel Engine had worked?
Post by: J N Winkler on April 17, 2023, 03:39:44 AM
Re. LS swaps:  pushrod engines . . . in 2023?
Title: Re: What if the Wankel Engine had worked?
Post by: Max Rockatansky on April 17, 2023, 10:40:16 AM
For what it's worth the LS despite being a pushrod engine is probably the easiest available modern engine swap.  GM has an absurdly huge aftermarket parts catalog.
Title: Re: What if the Wankel Engine had worked?
Post by: Road Hog on April 21, 2023, 05:13:07 PM
I drove an old Mazda with a rotary engine in college. It ran like a scalded dog but it used oil like nobody's business.
Title: Re: What if the Wankel Engine had worked?
Post by: kphoger on April 21, 2023, 05:36:48 PM
Quote from: Road Hog on April 21, 2023, 05:13:07 PM
a scalded dog

(https://img.huffingtonpost.com/asset/60ad5096260000d99cb43dfb.jpeg)