alt Hacker NewsJapanese four-cylinder engine is so reliable still in production after 25 years
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25yr is "meeting expectations" for any mass market[1] engine designed after about the mid 1970s or so.
A design that is both not fundamentally flawed in some way and cutting edge enough for its time to not quickly rendered obsolete the steady increase in expectations should go far longer. A design that is "ok" and cutting edge will probably go 20-30yr. A design that is behind the times, and very good (easier to not make wrong design decisions when you're not on the cutting edge) will probably do 20-30yr as well.
[1] i.e. not some specialty truck or sports car thing that could become not worth making due to a shift in market conditions for the few segments where it's applicable.
GM/Chevrolet are still making small-block 350 engines, they started in the 1950's
The headline isn’t really true. The K series of engines has been in production for 25 years but it has been redesigned along the way.
The article mentions this further down:
> The K20C is Honda's current-generation of the K-Series range, upgraded to deliver strong real-world efficiency and long-term reliability across the Honda and Acura catalogs. It's also a redesign that meets stricter global emissions rules and tighter thermal demands that come with modern turbocharging.
The original K20A has been out of production for a long time.
Each iteration of the engine shares a lot in common with the previous iteration, but the redesigns have been significant enough that I wouldn’t say it’s accurate to claim that one engine has been in production for 25 years.
I don't think that lack of reliability is the key factor for why new motors are still being developed. Fuel efficiency or changing emission standards are two points that come to mind that drive further optimizations.
"Engine failure" is something everyone thought was a last century problem, yet it's back. Some blame extra thin oils, and some are pointing to cheap parts (ex. plastic manifolds and plastic timing guides). There are now engine lawsuits in 2015-2025 model vehicles from all the big vehicle manufacturers, with new failures clustering in late models. They literally don't make them like they used to.
When I was a kid I wanted a classic Mini with a transplanted Honda K-Series engine.
It's a big engine for that little car but I'd completely forgotten about them over the years.
It's wild that people are still doing this: https://potentialmotorsport.com/
I might have to reserect that dream. :D
The "Mopar 318" (Chrysler LA engine) lasted almost 40 years: https://en.wikipedia.org/wiki/Chrysler_LA_engine
Google "K-series Cam lobe pitting".
Anyways, nice engines, but you don't need something to be exceptionally reliable to keep it in production for 25 years.
I always thought one of these would fit a Shelby cobra kit car really well but culturally ppl want to stick giant ford v8’s in them
reminds me of the LADA vs BMW meme
https://www.reddit.com/media?url=https%3A%2F%2Fi.redd.it%2Fn...
Toyota 5A was in production 1987–2006, and IIRC was licensed to Chinese manufacturers afterwards. The A series as a whole lasted 1978–2006. Less modern than Honda K, but these were lovely engines. They just won't fail as long as you replace parts on time.
I strongly suspected it was going to be a Honda before even clicking the link. I traded in my RSX-s many years ago for Cherokee because kids. I miss that car, that was a lovely engine even though the low-end torque was a bit anemic.
What's impressive isn't just the longevity, but how gracefully it's evolved over two decades while still feeling relevant in today's turbocharged, emissions-strangled landscape
The Volvo modular engine is worth a short too, it ran for 26 years [1].
I’ve noticed Honda puts an emphasis on reducing stress. I have a 20 year old Honda which still runs fine because everything about it seems “overbuilt” - other owners say it runs fine without coolant, oil, etc - just keeps plugging along.
From my experience the K20 is indestructible.
I was flabbergasted driving a 2023 Honda Civic Sport during a trip to Thailand, easily one of the best-balanced cars I’ve driven. Makes me wonder if that model is using the same engine they’re talking about here
Did a BAR swap of a k20a2 into a EG civic. It’s such a fun car to drive, street or track.
One of the interesting quirks of the Honda K-series is that it spins “backwards”. If you try to mate one to a different transmission (or try to mate a different engine to a K-series transmission), it’s going to give you, uh, interesting results! Lots of people found out the hard way when they used their Fast & Furious inspiration to do JDM swaps :)
So what? The Rolls-Royce & Bentley L-series engine was made from 1959 to 2020, 60 years, (https://en.wikipedia.org/wiki/Rolls-Royce–Bentley_L-series_V...), and was only replaced because of mergers and change in ownership, not because of its capacities. It of course evolved quite some during that production span.
Engines used in general aviation have interchangeable parts from almost 100 years ago. You could warp a Lycoming engine mechanic in from 1942 using your time traveling phone booth and he'd be able to fix your 172 of any vintage.
So are the staright sixes from BMW. Running one generation behind B58.
Even before clicking through, I said to myself "... and it's made by Honda."
I don't know precisely what special sauce they have, but while I've parted with a couple of Hondas over the years due to rust or accessory breakdown (and one, sadly, to a crash; hey, I know the Fit has a reputation as a deathtrap, but it saved my life), I've never had one give me engine trouble.
Their starter has a very iconic sound too; I'm a little surprised marketing has never seemed to catch onto that. You can identify the sound of a Honda starting up in a parking lot.
Or the saab H engine, introduced in 1981 and is kicking around
Funny considering the K20A1 started off with a dogshit reputation and chain tensioner issues just like the F-series engines in the S2000 that honda refused to learn from.
But thanks to aftermarket support you can get third party parts to fix any issue with the K-series, and even see people turbocharging to get them north of 1,200hp. We've got a local guy with a k-swapped Acura NSX that is an absolute monster of a car.
I just sold my 2005 CRV with the same 4. At 170,000 miles, the engine burned no oil, started first crank every time, moved the car adequately, and got 25 mpg in an suv.
I replaced it with a Corolla hybrid. It gets 60 mpg. I have expectations of longevity for this one, too.
It's V6 but the 1GR-FE is probably the most reliable small car engine of all time. Easily 500k miles.
Some Diesel engines like VW 1.9 TDI PD were incredibly reliable. Still they wouldn't be legal today because of EU legislation.
That's a series of engines, not a single model. The FIAT FIRE [1] series has been in production for 36 years from 1985 to 2021 and, maybe you wouldn't expect it from FIAT, those engines were reliable.
[1] https://en.wikipedia.org/wiki/Fully_Integrated_Robotised_Eng...