What makes Honda 4 cylinder engines great?

[Scott_Tucker]

Honda was one of the first manufacturers to use selective fits.

This is where parts are divided into groups based on dimensional tolerances. For example, if a crank journal is supposed to be 2.000" +/- .001" then they might be divided into three groups - 1.999", 2.000", and 2.001".

The inside diameter of the installed bearing would have a similar tolerance and groups. For example, the bearing clearance spec may be .002". Therefore, the bearing inside diameter should be 2.002". The groups might be divided into 2.001", 2.002", and 2.003".

No machining process is perfect. The size of the crank journal, the diameter of the bearing bore, and the thickness of the bearing are all going to vary a minute amount from the specification.

By matching a part (the journal size)from one group with a part from a corresponding group (of the bearing bore) they are able to achieve that .002" with more accuracy on all their engines.

By holding everything to tighter dimensional tolerances, you achieve better quality control and fewer failures. Honda started using this in the 60's or 70's and the American companies didn't start until the 80's.

I have no doubt that an American engine these days can last as long as a Honda engine. It is the fact that they have been making reliable engines longer that makes Honda have the reputation of reliability.

 

[M1Accord]

Originally Posted By: Zako2
Honda was the king of 4-cylinder engines in the 90s. Their variable valve timing technology looked ages ahead of what other car makers were doing. The wear numbers for 4-cylinder engines (the 2.4L) also look very good in the UOA section. However, Honda pretty much coasted on its reputation through the past 10 years without being a technology leaders. They are among the _last_ to transition their cars at 6-speed automatic transmission from 5-speed, two-three years behind Ford for example. They also haven't been pushing forced induction as hard as other manufacturers. Acura's RDX, first attempt at forced induction, with turbo engine supposedly had issues.


Advance technology doesn't necessarily mean better technology. With the exception of the Honda Fit, all Honda I-4 vehicles get very good gas mileage. My Fit, gets about 37.6 mpg in 40% city/60% highway mix driving. My average commute is 38 miles, 10 of which can be classified as non-highway and I get 43.4 mpg. However, in city or non-highway driving involving traffic lights and other stop and go, it is horrible on gas. That is why each time I use it for non-commute driving, gas mileage drops. We all know it is due to their gear ratio to make the car more sporty than the 1.5 liter is since the 1.8 liter and 2.4 liter in the Civic and Accord get the same or better fuel economy per EPA testing. But I bet this low tech 1.5 liter engine will keep on running past 300k miles as long as I use the right oil and change it every 10k or under, regardless of what the service minder says.

Another thing I like about Honda is that they look nice even after many years. I am talking about the overall shape and design. My Accord has beautiful lines. So are the Prelude, CRX, CRV, and many Civics. I keep seeing the Civic wagon from the late 80's and early 90's around here and they look great. Some of them are 4x4/AWD and are fantastic when lowered slightly with nice wheels. I can't say the same for Toyota, GM, Ford, Chrysler, and many other makers' cars. Their offerings from the 80's and 90's look
like [censored]. Of course, the Big 3 got nice classic trucks and SUV but only GM and Dodge got nice looking trucks now. Most of Ford's round shape design make their SUV look like minivan on steroid and their trucks look like [censored].

I wouldn't buy a new vehicle from the Big 3 except the Wrangler and Mustang but they seem poorly put together. I guess you buy them for what they are and not quality control on build quality and Honda doesn't have anything to compete in those market. I definitely will never buy anything from Toyota except the Tundra and 4Runner, their cars are boring and their dealerships suck.

 

[M1Accord]

Originally Posted By: Christopher Hussey
Originally Posted By: JetStar
This could also be expanded to include Japanese in-line 4 cyl motorcycle engines. Hp per liter and reliability / durability is largely unmatched and available at a reasonable cost. Perhaps there is a relationship?


Yup. Superior (and often simplified) engineering is the key.


Agree

 

[Doog]

Honda has very strict manufacturing controls and develops it's suppliers over a longer period of time. This pays off in long term defect rates. They also are very strict about making changes to designs that are proven. They also spend more time and money testing.

 

[Merkava_4]

Originally Posted By: Scott_Tucker
Honda was one of the first manufacturers to use selective fits.

This is where parts are divided into groups based on dimensional tolerances. For example, if a crank journal is supposed to be 2.000" +/- .001" then they might be divided into three groups - 1.999", 2.000", and 2.001".

The inside diameter of the installed bearing would have a similar tolerance and groups. For example, the bearing clearance spec may be .002". Therefore, the bearing inside diameter should be 2.002". The groups might be divided into 2.001", 2.002", and 2.003".

No machining process is perfect. The size of the crank journal, the diameter of the bearing bore, and the thickness of the bearing are all going to vary a minute amount from the specification.

By matching a part (the journal size)from one group with a part from a corresponding group (of the bearing bore) they are able to achieve that .002" with more accuracy on all their engines.

By holding everything to tighter dimensional tolerances, you achieve better quality control and fewer failures. Honda started using this in the 60's or 70's and the American companies didn't start until the 80's.

I have no doubt that an American engine these days can last as long as a Honda engine. It is the fact that they have been making reliable engines longer that makes Honda have the reputation of reliability.



After reading your post, I'm picturing a Japanese guy somewhere with
a white lab coat and a micrometer sorting these parts out into groups.

 

[Hokiefyd]

Originally Posted By: JetStar
This could also be expanded to include Japanese in-line 4 cyl motorcycle engines. Hp per liter and reliability / durability is largely unmatched and available at a reasonable cost. Perhaps there is a relationship?


Honda, at its heart, is an engine builder. Look at all of its products across its various business sectors. Motorcycles/scooters, automobiles, and power equipment. Each one has a very specific type of engine designed and manufactured by Honda. They have the benefit of either being involved or having been involved in nearly every industry niche that involves internal combustion engines. They live it, and I think it shows in their engines, especially their 4-cylinder engines.

Everyone is bringing up reliability; I don't think Honda has a reliabilty advantage over anyone else. What I do think they have is a NVH advantage. Some of the domestic 4-cylinder engines were horrible in terms of NVH, or to use a simpler word, refinement. Until GM's Ecotec engine, or maybe some of Ford's European 4-cylinder engines, I don't think any of the Detroit Three had an engine that competed in terms of refinement. I've driven some of Chrysler's new 2.4L World Engines and am simply unimpressed; I'm sure they'll last a long time, but they have no soul, they don't encourage you to use the "go" pedal.

I personally don't care too much if something'll last 300,000 miles. I'm not likely to own the car that long anyway. But for the 100 or 150 thousand miles I DO own the car, I want to enjoy driving it.

I don't think there's anything "special" about Honda's 4-cylinder engines. There's no magic elixir that gets poured into the casting, and there's no pixie dust sprinkled into the oil during assembly. They're simply very good designs that have stood the test of time.

 

[supton]

Is there anything special about other's 4 bangers? My VW I4 hit 263kmiles this week. I think with the aftermarket tune it is rather smooth and powerful, albeit with some turbo lag (140hp/250ft-lb is my guesstimate). Oil consumption varies, 0.5 to 1qt over 10kmiles, sometimes less (I think it's dependant upon driving conditions).

The wife's '01 Civic was kinda boring. If I got on it, and let the rev's climb--not much happened, really. I don't recall it ever taking off like a rocket. My '00 Saturn 1.9 SOHC was even more dead; it was useless above 3k. And was the typical oil burner. Our Toyota 2.5L has surprised me once or twice, once it gets above 4k; but even still, it usually doesn't. But it is one of the quietest and smoothest engines I've ever driven; haven't been able to lug it yet. It seems to just crank along, regardless of load/rpm.

 

[grampi]

Originally Posted By: ls1mike
Originally Posted By: JRed
Generally speaking, Honda and Toyota are regarded as using OEM parts that are of a higher quality than those used by GM and the assembly of the cars in previous model generations has been much better than their comparable GM counterparts.

I believe there was an article citing the fact that Toyotas built in America have more problems per 100 vehicles than Toyotas built in Japan. Many people attribute this to the Japanese QC being much more strict.

I have to ask why no mention of Ford or Mopar 4 Cyls. GM the easy target? Their 4 bangers are no better or worse.


Simply not true.

 

[grampi]

Originally Posted By: JetStar
This could also be expanded to include Japanese in-line 4 cyl motorcycle engines. Hp per liter and reliability / durability is largely unmatched and available at a reasonable cost. Perhaps there is a relationship?


Even the Japanese motorcycle engines of other configurations are superior to other makes...I believe it is due to superior design...

 

[javacontour]

Others have mentioned the key points. I too had heard Honda characterized as an engine builder that happens to make cars, motorcycles, etc.

Also the Japanese QC deal. My anecdotal evidence was my unofficial tour of the Ford Explorer plant when they were still built here in St. Louis. They built RHD Explorers for Japan and the IT guy giving me the tour said they put those units through extra QC because the Japanese would not accept what we, the American Consumer is willing to accept as quality.

So there is a difference in what each market considers quality.

Finally, I think the US carmakers are catching up. There were some examples where the US was really trying. I think of the Quad4, getting 180 and later 195hp out of 2.3L engines. But not without problems as I think they had head gasket issues mating aluminum heads to iron blocks. Ford with their Zetec and later Duratec 4 cylinder engines, and Chrysler with their world engine, designed jointly with Mitsubishi and Hyundai.

But there were some real misses too. Think of the Vega 4 cylinder engine. Interesting idea, but a flawed execution.

I don't think it was because Detroit could not make world class 4 cylinder engines. I think it was largely because they were run too long by bean-counters and other non-car folks. So "good enough" was the mantra that ultimately drove the train off the tracks.

There are some interesting cars coming out of Detroit, so it's a good time to be a car enthusiast today.

 

[Hokiefyd]

Originally Posted By: supton
Our Toyota 2.5L has surprised me once or twice, once it gets above 4k; but even still, it usually doesn't. But it is one of the quietest and smoothest engines I've ever driven; haven't been able to lug it yet. It seems to just crank along, regardless of load/rpm.


As you know, I had the same 2AR-FE in my Camry, and I think that engine is one of the very best I've owned, of any type. What a smooth mill that is. And there seems to be power everywhere. Of course, I'm comparing a lighter FWD sedan with a heaver AWD SUV, but the engine in our CR-V begins to really pick up steam at about 2,500 rpm, whereas Toyota's 2.5L had good torque right off idle. Our Honda's 2.4L doesn't really care to pull a load below about 1,600 rpm, but the Toyota would happily.

 

[Hokiefyd]

Originally Posted By: javacontour
I don't think it was because Detroit could not make world class 4 cylinder engines. I think it was largely because they were run too long by bean-counters and other non-car folks. So "good enough" was the mantra that ultimately drove the train off the tracks.


That, and the United States has never traditionally embraced inline-4s like other cultures have. This is the land of the V-8 (and more recently, the V-6), and American V-8s have long been at or near the top of the heap. Early 4-cylinder development here was lagging far behind other continents. Pontiac's Iron Duke? Gimme a break. True, it didn't even make the power to destruct itself, but even at that time, there were much more polished inline-4s from Europe that embarassed Pontiac's 2.5L. GM's 2.4L Quad 4 was a real step forward, and that engine had a lot of spunk for its size and its day. It wasn't the most refined inline-4 in the world, but it had plenty of power.

I think the Ecotec is the strongest signal yet that Detroit is getting serious about 4-cylinder engines. The Ecotec in our 2012 Malibu at work has some real spunk to it, some real zeal. The transmission programming lets it down, but you can shift it manually, and it's actually quite a fun engine to work around. It reminds me a lot of Toyota's 2AR-FE...there seems to be power everywhere on the tachometer, it's very smooth with just the right amount of "hum" to it. To me, the Ecotec has a certain soul do it that defines many of Honda inline-4s and that many of Detroit's inline-4s have lacked.

I can't agree more that it's a great time today to be a car enthusiast, no matter what brand you like or follow.

 

[grampi]

Originally Posted By: Hokiefyd
Originally Posted By: supton
Our Toyota 2.5L has surprised me once or twice, once it gets above 4k; but even still, it usually doesn't. But it is one of the quietest and smoothest engines I've ever driven; haven't been able to lug it yet. It seems to just crank along, regardless of load/rpm.


As you know, I had the same 2AR-FE in my Camry, and I think that engine is one of the very best I've owned, of any type. What a smooth mill that is. And there seems to be power everywhere. Of course, I'm comparing a lighter FWD sedan with a heaver AWD SUV, but the engine in our CR-V begins to really pick up steam at about 2,500 rpm, whereas Toyota's 2.5L had good torque right off idle. Our Honda's 2.4L doesn't really care to pull a load below about 1,600 rpm, but the Toyota would happily.


That has long been a Honda/Toyota thing. Toyota's 1.8 is the same when compared to Honda's 1.8. The Toyota engine seems to have power and torque throughout it's entire RPM range, while the Honda lacks power below a certain RPM, them comes to life in the upper RPM range...this is why I prefer Toyota engines over Honda's...

 

[CharBaby]

An engineer friend of mine once told me that, not only were Honda engines more refined(NVH)as Hokiefyd mentioned but, Honda also did aluminum better than any other engine mfg. What exactly that means(cast/fordged), IDK! Their fuel systems were also top notch allowing their engines to purr like a kitten, deliver all of the fuel the engine needed over it's rev range and power band, achieve better MPG than the competition while often making more power, and this was just a carburator(s)

Also, that Honda was using forged crankshafts instead of cast mainly due to, where their engines could rev, more than where most folks would drive'em. This is what made factory Honda engines so popular with the fast&furious crowd. Their internal polishing and balancing was ahead of the competition.

Honda was also experimenting with titanium connecting rods very early in the 80's to reduce reciprocating mass along with shorter skirt pistons. This weight reduction in the 80's was the "Skyactive" of it's day!

They developed their own fuel injection system instead of relying on outside sources, practicaly invented V-Tech(at least for the mass production cars) and single cam'd 4 valves per/cylinder better than other companies could double cam'd 4 valves per/cylinder in terms of refinement, lower emmissions, power and fuel economy. These are all things that the car owner would never know or feel. We'd just drive'em!

The list goes on and on! But, there was nothing that the owner would know as I mentioned and I now think that Honda has realized this and now allowing other mfg to spend their R&D $ and maybe follow instead of lead the pack. IDK!

 

[mechtech2]

Originally Posted By: Christopher Hussey
Originally Posted By: JetStar
This could also be expanded to include Japanese in-line 4 cyl motorcycle engines. Hp per liter and reliability / durability is largely unmatched and available at a reasonable cost. Perhaps there is a relationship?


Yup. Superior (and often simplified) engineering is the key.

Actually, the opposite [concerning simplification]. Japanese car Mfrs use a lot more parts to affect the same outcome as others.
Metals are good, but are can't take being overstressed by load or torque. Rubber stuff is better than average.
Older Honda engines burned oil and clogged the cats.

 

[Schmoe]

One key note people are leaving out.....the actual driver. Face it, exactly whom buys Honda's? Not necessarily the younger crowd, or if they do, they aren't interested in making "ricers" out of them and then flogging the engine in the name of speed. That particular demographic is a better maintenance minded type of consumer and will have the oil changed and have regular service performed on them as opposed to others.

 

[punisher]

When I step in the "WABAC Machine" (look it up) and go back 25-30 years I can see where there was a clear difference in what Japan offered and what US OEMs offered. Comparing any 80's Honda or Toyota engine to an American designed 4 banger of the same vintage was not pretty. Iron Duke? 2.3L HSC? If you owned either engine you knew when your oil was low because your driveway was clean.

Honda specifically (just my opinion) really does their homework when it comes to metallurgy, and the quality control during casting/forging of their components.

 

[hattaresguy]

There not really that great, just cheap. They built a ton of them, and worked the bugs out so the owners could weld the hood shut for 200k miles.

In the 90's or whenever Vtec came out it wasn't really anything special the Germans had been doing it for years. Honda was just able to do it at a much lower price point.

 

[Hokiefyd]

The Germans were operating their engines on different cam lobes (not changing just timing, but lift also) for years prior to 1983? VTEC was implemented on motorcycle engines in 1983 and on automobile engines in 1989.

 

[zzyzzx]

Personally I would not consider an interference engine to be "great", which is what all or most of those Honda 4 cylinder engines are.