Why all the Big NA Engines?

[pup2]

Just wondering -- di ba mas efficient ang turbo? Instead of raising engine displacements such as from 16. to 1.8/2.0for compact cars, why not just add turbos to 1.6 engines?

[Alpha_One]

There's no replacement for displacement.

To be exact, it's a tradeoff. The benefits of a turbo may be had at much less expense through a slightly bigger engine. It would be simpler and none of those turbo quirks like lag, heat, engine knock...

If you're a car designer from the 1950s, or in the 2000's working on an econobox, the turbo may simply be too expensive and complicated for the car in mind.

Also, notice that turbos are much more common on diesel engines. That's mainly because diesel engines tend to be overbuilt due to their nature of operation. Small amounts of boost wouldn't affect anything on a diesel that would cause knock and ping and blown gaskets on a petrol engine (barring huge redesigns).

To put it simply, there's what the economists call There Ain't No Such Thing as a Free Lunch.

[niky]

Cost, I think.

Turbo engines have more components than comparable power NA engines. More in-bay heat. More insulation, etcetera.

Bigger NA engines tend to be smoother in terms of power delivery than turbocharged lumps... traditionally... new variable geometry turbos, high pressure injectors and better computer control help make newer turbo engines act more like NA engines.

But at a cost.

That's why American manufacturers went with big displacement engines for so long. They used more gas, yes, but they cost less to manufacture and develop.

[OTEP]

Turbos are not necessarily more efficient when compared to a large normally aspirated engine. Take a look at the Acura RDX with its 4 cylinder turbo. It has the fuel economy of a V6 while being more complex and not as smooth.

Small engines are popular in some markets because larger displacements tend to be taxed higher. And to make power in a small engine, you had to resort to turbocharging or supercharging.

That was also the prevailing system in the local market unting recently when we went to value based taxation. Since the shift in the tax system, there has been an influx of larger displacement engines in the local market.

http://www.caranddriver.com/comparis...acura-rdx.html

To decrease weight and increase fuel economy, Acura fitted the RDX with a turbocharged four-cylinder engine, its first forced-induction anything. A four-banger in a vehicle costing close to 40 grand is a risky ploy, but the RDX did emerge as the lightest member of our trio, and its 6.5-second sprint to 60 mph makes it an Olympic luge in the world of SUVs. Notice, however, that the 20-hp-more-potent BMW X3 matched the RDX’s quarter-mile trap speed, and by the time both were humping along at 100 mph, the BMW was a 10th ahead. What’s more, the RDX’s observed fuel economy was 3 mpg worse than the ballsier BMW’s. One thing about turbos—they’re thirsty.

[pup2]

Cool. 3 lang sagot but very informative.

Pero paano kung current situation? Would you prefer to have, say, a 1.6 Turbo (gas ha) compact or a 1.8/2.0 compact -- assuming mas mura ng konti yung 1.6 (say, 100k?)? At bakit?

[Jun aka Pekto]

Would you prefer to have, say, a 1.6 Turbo (gas ha) compact or a 1.8/2.0 compact

I'm assuming this is one particular car with different engine options. Chances are the 1.6 turbo will have dramatically more hp/torque than the 1.8/2.0. In fact, hp/torque for the turbo 1.6 will probably approach that of smaller V6s. But, the added strain of a turbo will takes its toll down the road in accelerated wear and tear and high-maintenance costs. That's probably why a number of cars I knew that had turbo 4s initially moved to high output N/A 4's or bigger engines:

Ford Thunderbird (not the convertible)- moved from turbo 4 to V6/supercharged V6
Pontiac Grand Prix - turbo 4 to V6/supercharged V6
Ford Probe GT - turbo 4 to V6
Chrysler Lebaron - turbo 4 to V6
VW Corrado - turbo 4 to V6
Mitsubishi Eclipse- turbo 4 to V6

Other turbo 4 cars simply died out:
Izuzu Impulse RS
Plymouth Laser RS Turbo/Eagle talon TSi
Dodge Daytona

[Jun aka Pekto]

I also have to add an anecdote while reminescing about old times.....

A comparison of my then-new 91 Plymouth Laser RS Turbo and my ex fiancee's Z-28 IROC-Z. We put both cars through the same amount of abuse and even though her car was older, there wasn't any problems with its 5.7L V8. On the other hand, the 2.0L 4G63 turbo engine of my Laser started to develop oil leaks even though it's almost 2 years younger. The stress the turbo engine goes through is enormous.

That's why I haven't bought another turbo car since my 91 DSM. I opted for V6-equipped cars instead. Displacement really matters. Sure, I miss a turbo when tackling the thinner air of snowy mountain roads and a V6 doesn't have the raw power delivery and lighter weight of a turbo 4. But, the overall maintenance costs are a lot less. We have a 95 2.5L V6 Ford Contour SE. The maintenance costs for that has been way, way less than my Laser for the same elapsed time frame.

Turbos should really only be on small sports cars. It's perfect for cars like the Pontiac Solstice (which does have a turbo version) and a MazdaSpeed 3/Miata. I'm divided on having turbos on midsize cars like the MazdaSpeed 6 because of the increasing weight. Like I said earlier, maybe turbo cars have improved. We'll see. I'm on the lookout for the MazdaSpeed 6 long-term reliability reports.

[rion]

Imo, Turbos are like cheating on olympic sports like on illegal steroids, and could cause damage in the long term for the sports player.

The Turbo technolgy is still awesome, I just realized recently how much air it could give. The BMW diesel class can even go 28Psi. almost like a Tire pressure but in bigger pipes.

[MAXBUWAYA]

On the Commercial Vehicle Side

A lot of 10 wheeler wing van (Japan surplus) are now 6 cylinder turbo

But Filipino buyers still want the 10cylinder NA.

Maintenance issue.

[badkuk]

imho, ang masama nga lang pag bigger engine, at idle, it still drinks up more fuel.


di ko lang sure if there's any existing engine/engine management system that addresses that. ung vtec thing afaik only shuts down cylinders at high cruising speeds, di ba?

[Jun aka Pekto]

Imo, Turbos are like cheating on olympic sports like on illegal steroids, and could cause damage in the long term for the sports player.

Turbos still has a certain appeal which is why I'm trying to keep my Laser within the family. I rather sign it over free to a relative than sell it to a stranger.

Anyway, a turbocharged engine is as valid as a N/A or supercharged engine. So long as people know what it means to own a turbo car then, there's no problem. Since most turbo car owners tend to be enthusiasts, maintenance costs are well...... irrelevant is the wrong word. Bah. it's too early in the morning to think......
Right now, if I was still single and lived in an apartment or condo, I'd probably have a turbo car of some sort in the parking lot. That turbocharged Pontiac Solstice looks mighty appealing. Also, I still long for a GMC Syclone. If I can find one in good shape.


http://www.phoenixgraphix.com/gm/9192gmcs.htm

Add: Subaru's probably the only company that have turbocharged cars right with its 2.5L turbo 4.

2.5L is pretty big for a 4-cylinder. Most other turbocharged cars have 2.0L or less. Maybe that extra 0.5L makes a difference.

[Dr.Kamiya]

Add: Subaru's probably the only company that have turbocharged cars right with its 2.5L turbo 4.

2.5L is pretty big for a 4-cylinder. Most other turbocharged cars have 2.0L or less. Maybe that extra 0.5L makes a difference.

I think the 2.5li was done so they could run less boost and pass US/EU emissions, and cut down manufacturing costs, using displacement instead of sophistication.

The Japanese STIs still have 2.0li engines, but actually produce better power (320hp for the S204 and RA-R, vs 300hp for US cars and 280hp elsewhere), and have more torque than the international market 2.5lis (320lb-ft JDM S204, RA-R, 310lb-ft STi, vs 300lb-ft for the 2.5li cars).

[niky]

2.5 is kinda an awkward size for inline-fours... it's big enough to have balance problems that 2 liter and below engines don't have... but then, a lot of manufacturers are going up that scale now, using balancer shafts to keep the engines from vibrating to pieces at high revs.

Subaru's advantage is that the boxer design makes smooth running a doodle even at that size, so even though they have the extra cost and complexity of running a boxer, they have less issues with the engine harmonics themselves... and man do they rev creamy.



Man, that was one of the first "sports" trucks, right? Would be interesting to have...

[OTEP]

The Syclone's 500lb bed capacity was it's weak point. The truck can only haul itself! hehehe.

But the Syclone and it's SUV counterpart (the Typhoon) are two of the more significant vehicles in recent automotive history.

[Jun aka Pekto]

The Syclone's 500lb bed capacity was it's weak point. The truck can only haul itself! hehehe.

But the Syclone and it's SUV counterpart (the Typhoon) are two of the more significant vehicles in recent automotive history.

The Syclone's actually a pretty small truck with a turbocharged V6 and AWD. It's more like a 2-seat sports car with a huge trunk. Most people who bought it treated it as such.

It does illustrate the thread's premise since during the heydays of the Syclone, there was also the Chevy 454 SS which was the big-displacement, N/A rival to the Syclone. Of course stock, the Syclone would spank the Chevy. But, I rarely saw a Chevy 454 SS in stock form. Every single one I've seen were modded in some way.

[Jun aka Pekto]

Man, that was one of the first "sports" trucks, right? Would be interesting to have...

I'm not sure if it was the first. I think the Chevy (Silverado) 454 SS was around a bit earlier. At least, I've seen a few 454 SS before I saw a Syclone. I didn't see a Syclone until late 1992. By then, I learned to watch out for the 454 SS. But, the Syclone was totally unknown to me. The first time I saw one (in Idaho) was when I got smoked by one.

[rion]

some people hate those whistle sounds. while I'm loving it. sounds like a Airplane... heck, I could trade for more louder whistle (not from air-leaks) than a louder exhaust.

though D4D's turbo sounds different (not too music for my ears). but whistle sound engages earlier compared to the old toyo's. (probably lesser lag than before?)

some engines when turned off, you could still hear the turbo as sound pitches go down. man... it is like a airplane shutting down it's engines.

[alwayz_yummy]

alam ko:

may 1.3 na turbo->4E-FTE-->paborito ng small-body rolla/charade owners..

ang toyota may: 1.6L 4a-ge in various forms:16-valve, supercharged, 20-valve, 20 valve-VVT at yung modified formula-atlantic ba yun... all 1.6L, pero iba iba ang power...

mitsu 4g92: mivec at non-mivec, turbo 4g63: sohc,dohc, turbo, non-turbo, and sa evo9 na MIVEC-turbo

eto alam ko matindi: 2.0 SR20DET lalo na yung SR20VET-->280ps *factory rate!

[deedee]

the cyclone was a a very tricked out truck back in the early 90s but if its american turbo cars were talkin here..who can forget the GNX.thats one mean V6 with a turbo from buick

the last of its kind.the buick GNX547

[Jun aka Pekto]

the cyclone was a a very tricked out truck back in the early 90s but if its american turbo cars were talkin here..who can forget the GNX.thats one mean V6 with a turbo from buick

the last of its kind.the buick GNX547

Nice. But, I also have to consider the 20th Anniversary Trans Am which was also a RWD turbo V6 and was slotted between the GNX and the Syclone. Well, they're all GM cars. That makes them family.

But, it's the same trend with the turbo 4's. Everyone wanted bigger cars with big engines in them instead of turbos. Anyone remember the 1984 Ford Mustang SVT which had a 2.3L turbocharged 4? Back then, memories of the last energy crisis was still fresh.

Add: I would say turbocharged cars have improved since those days. How much? I don't know. At least from my point of view, not enough. To me, it doesn't matter. The fun factor outweighs the maintenance costs although my wife have something to say about that......

But, among old-timers especially, there still exist the stigma of the leaky, high-maintenance turbo engine.